FFmpeg: libavcodec/mpeg4videodec.c Source File

00001 /*
00002  * MPEG4 decoder.
00003  * Copyright (c) 2000,2001 Fabrice Bellard
00004  * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00023 #define UNCHECKED_BITSTREAM_READER 1
00024 
00025 #include "libavutil/opt.h"
00026 #include "mpegvideo.h"
00027 #include "mpeg4video.h"
00028 #include "h263.h"
00029 #include "thread.h"
00030 
00031 // The defines below define the number of bits that are read at once for
00032 // reading vlc values. Changing these may improve speed and data cache needs
00033 // be aware though that decreasing them may need the number of stages that is
00034 // passed to get_vlc* to be increased.
00035 #define SPRITE_TRAJ_VLC_BITS 6
00036 #define DC_VLC_BITS 9
00037 #define MB_TYPE_B_VLC_BITS 4
00038 
00039 
00040 static VLC dc_lum, dc_chrom;
00041 static VLC sprite_trajectory;
00042 static VLC mb_type_b_vlc;
00043 
00044 static const int mb_type_b_map[4]= {
00045     MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
00046     MB_TYPE_L0L1 | MB_TYPE_16x16,
00047     MB_TYPE_L1 | MB_TYPE_16x16,
00048     MB_TYPE_L0 | MB_TYPE_16x16,
00049 };
00050 
00056 void ff_mpeg4_pred_ac(MpegEncContext * s, DCTELEM *block, int n,
00057                       int dir)
00058 {
00059     int i;
00060     int16_t *ac_val, *ac_val1;
00061     int8_t * const qscale_table = s->current_picture.f.qscale_table;
00062 
00063     /* find prediction */
00064     ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
00065     ac_val1 = ac_val;
00066     if (s->ac_pred) {
00067         if (dir == 0) {
00068             const int xy= s->mb_x-1 + s->mb_y*s->mb_stride;
00069             /* left prediction */
00070             ac_val -= 16;
00071 
00072             if(s->mb_x==0 || s->qscale == qscale_table[xy] || n==1 || n==3){
00073                 /* same qscale */
00074                 for(i=1;i<8;i++) {
00075                     block[s->dsp.idct_permutation[i<<3]] += ac_val[i];
00076                 }
00077             }else{
00078                 /* different qscale, we must rescale */
00079                 for(i=1;i<8;i++) {
00080                     block[s->dsp.idct_permutation[i<<3]] += ROUNDED_DIV(ac_val[i]*qscale_table[xy], s->qscale);
00081                 }
00082             }
00083         } else {
00084             const int xy= s->mb_x + s->mb_y*s->mb_stride - s->mb_stride;
00085             /* top prediction */
00086             ac_val -= 16 * s->block_wrap[n];
00087 
00088             if(s->mb_y==0 || s->qscale == qscale_table[xy] || n==2 || n==3){
00089                 /* same qscale */
00090                 for(i=1;i<8;i++) {
00091                     block[s->dsp.idct_permutation[i]] += ac_val[i + 8];
00092                 }
00093             }else{
00094                 /* different qscale, we must rescale */
00095                 for(i=1;i<8;i++) {
00096                     block[s->dsp.idct_permutation[i]] += ROUNDED_DIV(ac_val[i + 8]*qscale_table[xy], s->qscale);
00097                 }
00098             }
00099         }
00100     }
00101     /* left copy */
00102     for(i=1;i<8;i++)
00103         ac_val1[i    ] = block[s->dsp.idct_permutation[i<<3]];
00104 
00105     /* top copy */
00106     for(i=1;i<8;i++)
00107         ac_val1[8 + i] = block[s->dsp.idct_permutation[i   ]];
00108 
00109 }
00110 
00115 static inline int mpeg4_is_resync(MpegEncContext *s){
00116     int bits_count= get_bits_count(&s->gb);
00117     int v= show_bits(&s->gb, 16);
00118 
00119     if(s->workaround_bugs&FF_BUG_NO_PADDING && !s->resync_marker){
00120         return 0;
00121     }
00122 
00123     while(v<=0xFF){
00124         if(s->pict_type==AV_PICTURE_TYPE_B || (v>>(8-s->pict_type)!=1) || s->partitioned_frame)
00125             break;
00126         skip_bits(&s->gb, 8+s->pict_type);
00127         bits_count+= 8+s->pict_type;
00128         v= show_bits(&s->gb, 16);
00129     }
00130 
00131     if(bits_count + 8 >= s->gb.size_in_bits){
00132         v>>=8;
00133         v|= 0x7F >> (7-(bits_count&7));
00134 
00135         if(v==0x7F)
00136             return s->mb_num;
00137     }else{
00138         if(v == ff_mpeg4_resync_prefix[bits_count&7]){
00139             int len, mb_num;
00140             int mb_num_bits= av_log2(s->mb_num - 1) + 1;
00141             GetBitContext gb= s->gb;
00142 
00143             skip_bits(&s->gb, 1);
00144             align_get_bits(&s->gb);
00145 
00146             for(len=0; len<32; len++){
00147                 if(get_bits1(&s->gb)) break;
00148             }
00149 
00150             mb_num= get_bits(&s->gb, mb_num_bits);
00151             if(!mb_num || mb_num > s->mb_num || get_bits_count(&s->gb)+6 > s->gb.size_in_bits)
00152                 mb_num= -1;
00153 
00154             s->gb= gb;
00155 
00156             if(len>=ff_mpeg4_get_video_packet_prefix_length(s))
00157                 return mb_num;
00158         }
00159     }
00160     return 0;
00161 }
00162 
00163 static int mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb)
00164 {
00165     int i;
00166     int a= 2<<s->sprite_warping_accuracy;
00167     int rho= 3-s->sprite_warping_accuracy;
00168     int r=16/a;
00169     const int vop_ref[4][2]= {{0,0}, {s->width,0}, {0, s->height}, {s->width, s->height}}; // only true for rectangle shapes
00170     int d[4][2]={{0,0}, {0,0}, {0,0}, {0,0}};
00171     int sprite_ref[4][2];
00172     int virtual_ref[2][2];
00173     int w2, h2, w3, h3;
00174     int alpha=0, beta=0;
00175     int w= s->width;
00176     int h= s->height;
00177     int min_ab;
00178 
00179     if(w<=0 || h<=0)
00180         return -1;
00181 
00182     for(i=0; i<s->num_sprite_warping_points; i++){
00183         int length;
00184         int x=0, y=0;
00185 
00186         length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
00187         if(length){
00188             x= get_xbits(gb, length);
00189         }
00190         if(!(s->divx_version==500 && s->divx_build==413)) skip_bits1(gb); /* marker bit */
00191 
00192         length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
00193         if(length){
00194             y=get_xbits(gb, length);
00195         }
00196         skip_bits1(gb); /* marker bit */
00197         s->sprite_traj[i][0]= d[i][0]= x;
00198         s->sprite_traj[i][1]= d[i][1]= y;
00199     }
00200     for(; i<4; i++)
00201         s->sprite_traj[i][0]= s->sprite_traj[i][1]= 0;
00202 
00203     while((1<<alpha)<w) alpha++;
00204     while((1<<beta )<h) beta++; // there seems to be a typo in the mpeg4 std for the definition of w' and h'
00205     w2= 1<<alpha;
00206     h2= 1<<beta;
00207 
00208 // Note, the 4th point isn't used for GMC
00209     if(s->divx_version==500 && s->divx_build==413){
00210         sprite_ref[0][0]= a*vop_ref[0][0] + d[0][0];
00211         sprite_ref[0][1]= a*vop_ref[0][1] + d[0][1];
00212         sprite_ref[1][0]= a*vop_ref[1][0] + d[0][0] + d[1][0];
00213         sprite_ref[1][1]= a*vop_ref[1][1] + d[0][1] + d[1][1];
00214         sprite_ref[2][0]= a*vop_ref[2][0] + d[0][0] + d[2][0];
00215         sprite_ref[2][1]= a*vop_ref[2][1] + d[0][1] + d[2][1];
00216     } else {
00217         sprite_ref[0][0]= (a>>1)*(2*vop_ref[0][0] + d[0][0]);
00218         sprite_ref[0][1]= (a>>1)*(2*vop_ref[0][1] + d[0][1]);
00219         sprite_ref[1][0]= (a>>1)*(2*vop_ref[1][0] + d[0][0] + d[1][0]);
00220         sprite_ref[1][1]= (a>>1)*(2*vop_ref[1][1] + d[0][1] + d[1][1]);
00221         sprite_ref[2][0]= (a>>1)*(2*vop_ref[2][0] + d[0][0] + d[2][0]);
00222         sprite_ref[2][1]= (a>>1)*(2*vop_ref[2][1] + d[0][1] + d[2][1]);
00223     }
00224 /*    sprite_ref[3][0]= (a>>1)*(2*vop_ref[3][0] + d[0][0] + d[1][0] + d[2][0] + d[3][0]);
00225     sprite_ref[3][1]= (a>>1)*(2*vop_ref[3][1] + d[0][1] + d[1][1] + d[2][1] + d[3][1]); */
00226 
00227 // this is mostly identical to the mpeg4 std (and is totally unreadable because of that ...)
00228 // perhaps it should be reordered to be more readable ...
00229 // the idea behind this virtual_ref mess is to be able to use shifts later per pixel instead of divides
00230 // so the distance between points is converted from w&h based to w2&h2 based which are of the 2^x form
00231     virtual_ref[0][0]= 16*(vop_ref[0][0] + w2)
00232         + ROUNDED_DIV(((w - w2)*(r*sprite_ref[0][0] - 16*vop_ref[0][0]) + w2*(r*sprite_ref[1][0] - 16*vop_ref[1][0])),w);
00233     virtual_ref[0][1]= 16*vop_ref[0][1]
00234         + ROUNDED_DIV(((w - w2)*(r*sprite_ref[0][1] - 16*vop_ref[0][1]) + w2*(r*sprite_ref[1][1] - 16*vop_ref[1][1])),w);
00235     virtual_ref[1][0]= 16*vop_ref[0][0]
00236         + ROUNDED_DIV(((h - h2)*(r*sprite_ref[0][0] - 16*vop_ref[0][0]) + h2*(r*sprite_ref[2][0] - 16*vop_ref[2][0])),h);
00237     virtual_ref[1][1]= 16*(vop_ref[0][1] + h2)
00238         + ROUNDED_DIV(((h - h2)*(r*sprite_ref[0][1] - 16*vop_ref[0][1]) + h2*(r*sprite_ref[2][1] - 16*vop_ref[2][1])),h);
00239 
00240     switch(s->num_sprite_warping_points)
00241     {
00242         case 0:
00243             s->sprite_offset[0][0]= 0;
00244             s->sprite_offset[0][1]= 0;
00245             s->sprite_offset[1][0]= 0;
00246             s->sprite_offset[1][1]= 0;
00247             s->sprite_delta[0][0]= a;
00248             s->sprite_delta[0][1]= 0;
00249             s->sprite_delta[1][0]= 0;
00250             s->sprite_delta[1][1]= a;
00251             s->sprite_shift[0]= 0;
00252             s->sprite_shift[1]= 0;
00253             break;
00254         case 1: //GMC only
00255             s->sprite_offset[0][0]= sprite_ref[0][0] - a*vop_ref[0][0];
00256             s->sprite_offset[0][1]= sprite_ref[0][1] - a*vop_ref[0][1];
00257             s->sprite_offset[1][0]= ((sprite_ref[0][0]>>1)|(sprite_ref[0][0]&1)) - a*(vop_ref[0][0]/2);
00258             s->sprite_offset[1][1]= ((sprite_ref[0][1]>>1)|(sprite_ref[0][1]&1)) - a*(vop_ref[0][1]/2);
00259             s->sprite_delta[0][0]= a;
00260             s->sprite_delta[0][1]= 0;
00261             s->sprite_delta[1][0]= 0;
00262             s->sprite_delta[1][1]= a;
00263             s->sprite_shift[0]= 0;
00264             s->sprite_shift[1]= 0;
00265             break;
00266         case 2:
00267             s->sprite_offset[0][0]= (sprite_ref[0][0]<<(alpha+rho))
00268                                                   + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][0])
00269                                                   + ( r*sprite_ref[0][1] - virtual_ref[0][1])*(-vop_ref[0][1])
00270                                                   + (1<<(alpha+rho-1));
00271             s->sprite_offset[0][1]= (sprite_ref[0][1]<<(alpha+rho))
00272                                                   + (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-vop_ref[0][0])
00273                                                   + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][1])
00274                                                   + (1<<(alpha+rho-1));
00275             s->sprite_offset[1][0]= ( (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][0] + 1)
00276                                      +( r*sprite_ref[0][1] - virtual_ref[0][1])*(-2*vop_ref[0][1] + 1)
00277                                      +2*w2*r*sprite_ref[0][0]
00278                                      - 16*w2
00279                                      + (1<<(alpha+rho+1)));
00280             s->sprite_offset[1][1]= ( (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-2*vop_ref[0][0] + 1)
00281                                      +(-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][1] + 1)
00282                                      +2*w2*r*sprite_ref[0][1]
00283                                      - 16*w2
00284                                      + (1<<(alpha+rho+1)));
00285             s->sprite_delta[0][0]=   (-r*sprite_ref[0][0] + virtual_ref[0][0]);
00286             s->sprite_delta[0][1]=   (+r*sprite_ref[0][1] - virtual_ref[0][1]);
00287             s->sprite_delta[1][0]=   (-r*sprite_ref[0][1] + virtual_ref[0][1]);
00288             s->sprite_delta[1][1]=   (-r*sprite_ref[0][0] + virtual_ref[0][0]);
00289 
00290             s->sprite_shift[0]= alpha+rho;
00291             s->sprite_shift[1]= alpha+rho+2;
00292             break;
00293         case 3:
00294             min_ab= FFMIN(alpha, beta);
00295             w3= w2>>min_ab;
00296             h3= h2>>min_ab;
00297             s->sprite_offset[0][0]=  (sprite_ref[0][0]<<(alpha+beta+rho-min_ab))
00298                                    + (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-vop_ref[0][0])
00299                                    + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-vop_ref[0][1])
00300                                    + (1<<(alpha+beta+rho-min_ab-1));
00301             s->sprite_offset[0][1]=  (sprite_ref[0][1]<<(alpha+beta+rho-min_ab))
00302                                    + (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-vop_ref[0][0])
00303                                    + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-vop_ref[0][1])
00304                                    + (1<<(alpha+beta+rho-min_ab-1));
00305             s->sprite_offset[1][0]=  (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-2*vop_ref[0][0] + 1)
00306                                    + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-2*vop_ref[0][1] + 1)
00307                                    + 2*w2*h3*r*sprite_ref[0][0]
00308                                    - 16*w2*h3
00309                                    + (1<<(alpha+beta+rho-min_ab+1));
00310             s->sprite_offset[1][1]=  (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-2*vop_ref[0][0] + 1)
00311                                    + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-2*vop_ref[0][1] + 1)
00312                                    + 2*w2*h3*r*sprite_ref[0][1]
00313                                    - 16*w2*h3
00314                                    + (1<<(alpha+beta+rho-min_ab+1));
00315             s->sprite_delta[0][0]=   (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3;
00316             s->sprite_delta[0][1]=   (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3;
00317             s->sprite_delta[1][0]=   (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3;
00318             s->sprite_delta[1][1]=   (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3;
00319 
00320             s->sprite_shift[0]= alpha + beta + rho - min_ab;
00321             s->sprite_shift[1]= alpha + beta + rho - min_ab + 2;
00322             break;
00323     }
00324     /* try to simplify the situation */
00325     if(   s->sprite_delta[0][0] == a<<s->sprite_shift[0]
00326        && s->sprite_delta[0][1] == 0
00327        && s->sprite_delta[1][0] == 0
00328        && s->sprite_delta[1][1] == a<<s->sprite_shift[0])
00329     {
00330         s->sprite_offset[0][0]>>=s->sprite_shift[0];
00331         s->sprite_offset[0][1]>>=s->sprite_shift[0];
00332         s->sprite_offset[1][0]>>=s->sprite_shift[1];
00333         s->sprite_offset[1][1]>>=s->sprite_shift[1];
00334         s->sprite_delta[0][0]= a;
00335         s->sprite_delta[0][1]= 0;
00336         s->sprite_delta[1][0]= 0;
00337         s->sprite_delta[1][1]= a;
00338         s->sprite_shift[0]= 0;
00339         s->sprite_shift[1]= 0;
00340         s->real_sprite_warping_points=1;
00341     }
00342     else{
00343         int shift_y= 16 - s->sprite_shift[0];
00344         int shift_c= 16 - s->sprite_shift[1];
00345         for(i=0; i<2; i++){
00346             s->sprite_offset[0][i]<<= shift_y;
00347             s->sprite_offset[1][i]<<= shift_c;
00348             s->sprite_delta[0][i]<<= shift_y;
00349             s->sprite_delta[1][i]<<= shift_y;
00350             s->sprite_shift[i]= 16;
00351         }
00352         s->real_sprite_warping_points= s->num_sprite_warping_points;
00353     }
00354     return 0;
00355 }
00356 
00361 int ff_mpeg4_decode_video_packet_header(MpegEncContext *s)
00362 {
00363     int mb_num_bits= av_log2(s->mb_num - 1) + 1;
00364     int header_extension=0, mb_num, len;
00365 
00366     /* is there enough space left for a video packet + header */
00367     if( get_bits_count(&s->gb) > s->gb.size_in_bits-20) return -1;
00368 
00369     for(len=0; len<32; len++){
00370         if(get_bits1(&s->gb)) break;
00371     }
00372 
00373     if(len!=ff_mpeg4_get_video_packet_prefix_length(s)){
00374         av_log(s->avctx, AV_LOG_ERROR, "marker does not match f_code\n");
00375         return -1;
00376     }
00377 
00378     if(s->shape != RECT_SHAPE){
00379         header_extension= get_bits1(&s->gb);
00380         //FIXME more stuff here
00381     }
00382 
00383     mb_num= get_bits(&s->gb, mb_num_bits);
00384     if(mb_num>=s->mb_num){
00385         av_log(s->avctx, AV_LOG_ERROR, "illegal mb_num in video packet (%d %d) \n", mb_num, s->mb_num);
00386         return -1;
00387     }
00388 
00389     s->mb_x= mb_num % s->mb_width;
00390     s->mb_y= mb_num / s->mb_width;
00391 
00392     if(s->shape != BIN_ONLY_SHAPE){
00393         int qscale= get_bits(&s->gb, s->quant_precision);
00394         if(qscale)
00395             s->chroma_qscale=s->qscale= qscale;
00396     }
00397 
00398     if(s->shape == RECT_SHAPE){
00399         header_extension= get_bits1(&s->gb);
00400     }
00401     if(header_extension){
00402         int time_incr=0;
00403 
00404         while (get_bits1(&s->gb) != 0)
00405             time_incr++;
00406 
00407         check_marker(&s->gb, "before time_increment in video packed header");
00408         skip_bits(&s->gb, s->time_increment_bits); /* time_increment */
00409         check_marker(&s->gb, "before vop_coding_type in video packed header");
00410 
00411         skip_bits(&s->gb, 2); /* vop coding type */
00412         //FIXME not rect stuff here
00413 
00414         if(s->shape != BIN_ONLY_SHAPE){
00415             skip_bits(&s->gb, 3); /* intra dc vlc threshold */
00416 //FIXME don't just ignore everything
00417             if(s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
00418                 if(mpeg4_decode_sprite_trajectory(s, &s->gb) < 0)
00419                     return -1;
00420                 av_log(s->avctx, AV_LOG_ERROR, "untested\n");
00421             }
00422 
00423             //FIXME reduced res stuff here
00424 
00425             if (s->pict_type != AV_PICTURE_TYPE_I) {
00426                 int f_code = get_bits(&s->gb, 3);       /* fcode_for */
00427                 if(f_code==0){
00428                     av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (f_code=0)\n");
00429                 }
00430             }
00431             if (s->pict_type == AV_PICTURE_TYPE_B) {
00432                 int b_code = get_bits(&s->gb, 3);
00433                 if(b_code==0){
00434                     av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (b_code=0)\n");
00435                 }
00436             }
00437         }
00438     }
00439     //FIXME new-pred stuff
00440 
00441     return 0;
00442 }
00443 
00449 static inline int get_amv(MpegEncContext *s, int n){
00450     int x, y, mb_v, sum, dx, dy, shift;
00451     int len = 1 << (s->f_code + 4);
00452     const int a= s->sprite_warping_accuracy;
00453 
00454     if(s->workaround_bugs & FF_BUG_AMV)
00455         len >>= s->quarter_sample;
00456 
00457     if(s->real_sprite_warping_points==1){
00458         if(s->divx_version==500 && s->divx_build==413)
00459             sum= s->sprite_offset[0][n] / (1<<(a - s->quarter_sample));
00460         else
00461             sum= RSHIFT(s->sprite_offset[0][n]<<s->quarter_sample, a);
00462     }else{
00463         dx= s->sprite_delta[n][0];
00464         dy= s->sprite_delta[n][1];
00465         shift= s->sprite_shift[0];
00466         if(n) dy -= 1<<(shift + a + 1);
00467         else  dx -= 1<<(shift + a + 1);
00468         mb_v= s->sprite_offset[0][n] + dx*s->mb_x*16 + dy*s->mb_y*16;
00469 
00470         sum=0;
00471         for(y=0; y<16; y++){
00472             int v;
00473 
00474             v= mb_v + dy*y;
00475             //XXX FIXME optimize
00476             for(x=0; x<16; x++){
00477                 sum+= v>>shift;
00478                 v+= dx;
00479             }
00480         }
00481         sum= RSHIFT(sum, a+8-s->quarter_sample);
00482     }
00483 
00484     if      (sum < -len) sum= -len;
00485     else if (sum >= len) sum= len-1;
00486 
00487     return sum;
00488 }
00489 
00496 static inline int mpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
00497 {
00498     int level, code;
00499 
00500     if (n < 4)
00501         code = get_vlc2(&s->gb, dc_lum.table, DC_VLC_BITS, 1);
00502     else
00503         code = get_vlc2(&s->gb, dc_chrom.table, DC_VLC_BITS, 1);
00504     if (code < 0 || code > 9 /* && s->nbit<9 */){
00505         av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
00506         return -1;
00507     }
00508     if (code == 0) {
00509         level = 0;
00510     } else {
00511         if(IS_3IV1){
00512             if(code==1)
00513                 level= 2*get_bits1(&s->gb)-1;
00514             else{
00515                 if(get_bits1(&s->gb))
00516                     level = get_bits(&s->gb, code-1) + (1<<(code-1));
00517                 else
00518                     level = -get_bits(&s->gb, code-1) - (1<<(code-1));
00519             }
00520         }else{
00521             level = get_xbits(&s->gb, code);
00522         }
00523 
00524         if (code > 8){
00525             if(get_bits1(&s->gb)==0){ /* marker */
00526                 if(s->err_recognition&(AV_EF_BITSTREAM|AV_EF_COMPLIANT)){
00527                     av_log(s->avctx, AV_LOG_ERROR, "dc marker bit missing\n");
00528                     return -1;
00529                 }
00530             }
00531         }
00532     }
00533 
00534     return ff_mpeg4_pred_dc(s, n, level, dir_ptr, 0);
00535 }
00536 
00541 static int mpeg4_decode_partition_a(MpegEncContext *s){
00542     int mb_num;
00543     static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
00544 
00545     /* decode first partition */
00546     mb_num=0;
00547     s->first_slice_line=1;
00548     for(; s->mb_y<s->mb_height; s->mb_y++){
00549         ff_init_block_index(s);
00550         for(; s->mb_x<s->mb_width; s->mb_x++){
00551             const int xy= s->mb_x + s->mb_y*s->mb_stride;
00552             int cbpc;
00553             int dir=0;
00554 
00555             mb_num++;
00556             ff_update_block_index(s);
00557             if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
00558                 s->first_slice_line=0;
00559 
00560             if(s->pict_type==AV_PICTURE_TYPE_I){
00561                 int i;
00562 
00563                 do{
00564                     if(show_bits_long(&s->gb, 19)==DC_MARKER){
00565                         return mb_num-1;
00566                     }
00567 
00568                     cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
00569                     if (cbpc < 0){
00570                         av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
00571                         return -1;
00572                     }
00573                 }while(cbpc == 8);
00574 
00575                 s->cbp_table[xy]= cbpc & 3;
00576                 s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
00577                 s->mb_intra = 1;
00578 
00579                 if(cbpc & 4) {
00580                     ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
00581                 }
00582                 s->current_picture.f.qscale_table[xy]= s->qscale;
00583 
00584                 s->mbintra_table[xy]= 1;
00585                 for(i=0; i<6; i++){
00586                     int dc_pred_dir;
00587                     int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
00588                     if(dc < 0){
00589                         av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
00590                         return -1;
00591                     }
00592                     dir<<=1;
00593                     if(dc_pred_dir) dir|=1;
00594                 }
00595                 s->pred_dir_table[xy]= dir;
00596             }else{ /* P/S_TYPE */
00597                 int mx, my, pred_x, pred_y, bits;
00598                 int16_t * const mot_val = s->current_picture.f.motion_val[0][s->block_index[0]];
00599                 const int stride= s->b8_stride*2;
00600 
00601 try_again:
00602                 bits= show_bits(&s->gb, 17);
00603                 if(bits==MOTION_MARKER){
00604                     return mb_num-1;
00605                 }
00606                 skip_bits1(&s->gb);
00607                 if(bits&0x10000){
00608                     /* skip mb */
00609                     if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
00610                         s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
00611                         mx= get_amv(s, 0);
00612                         my= get_amv(s, 1);
00613                     }else{
00614                         s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
00615                         mx=my=0;
00616                     }
00617                     mot_val[0       ]= mot_val[2       ]=
00618                     mot_val[0+stride]= mot_val[2+stride]= mx;
00619                     mot_val[1       ]= mot_val[3       ]=
00620                     mot_val[1+stride]= mot_val[3+stride]= my;
00621 
00622                     if(s->mbintra_table[xy])
00623                         ff_clean_intra_table_entries(s);
00624                     continue;
00625                 }
00626 
00627                 cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
00628                 if (cbpc < 0){
00629                     av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
00630                     return -1;
00631                 }
00632                 if(cbpc == 20)
00633                     goto try_again;
00634 
00635                 s->cbp_table[xy]= cbpc&(8+3); //8 is dquant
00636 
00637                 s->mb_intra = ((cbpc & 4) != 0);
00638 
00639                 if(s->mb_intra){
00640                     s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
00641                     s->mbintra_table[xy]= 1;
00642                     mot_val[0       ]= mot_val[2       ]=
00643                     mot_val[0+stride]= mot_val[2+stride]= 0;
00644                     mot_val[1       ]= mot_val[3       ]=
00645                     mot_val[1+stride]= mot_val[3+stride]= 0;
00646                 }else{
00647                     if(s->mbintra_table[xy])
00648                         ff_clean_intra_table_entries(s);
00649 
00650                     if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
00651                         s->mcsel= get_bits1(&s->gb);
00652                     else s->mcsel= 0;
00653 
00654                     if ((cbpc & 16) == 0) {
00655                         /* 16x16 motion prediction */
00656 
00657                         ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
00658                         if(!s->mcsel){
00659                             mx = ff_h263_decode_motion(s, pred_x, s->f_code);
00660                             if (mx >= 0xffff)
00661                                 return -1;
00662 
00663                             my = ff_h263_decode_motion(s, pred_y, s->f_code);
00664                             if (my >= 0xffff)
00665                                 return -1;
00666                             s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
00667                         } else {
00668                             mx = get_amv(s, 0);
00669                             my = get_amv(s, 1);
00670                             s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
00671                         }
00672 
00673                         mot_val[0       ]= mot_val[2       ] =
00674                         mot_val[0+stride]= mot_val[2+stride]= mx;
00675                         mot_val[1       ]= mot_val[3       ]=
00676                         mot_val[1+stride]= mot_val[3+stride]= my;
00677                     } else {
00678                         int i;
00679                         s->current_picture.f.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
00680                         for(i=0;i<4;i++) {
00681                             int16_t *mot_val= ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
00682                             mx = ff_h263_decode_motion(s, pred_x, s->f_code);
00683                             if (mx >= 0xffff)
00684                                 return -1;
00685 
00686                             my = ff_h263_decode_motion(s, pred_y, s->f_code);
00687                             if (my >= 0xffff)
00688                                 return -1;
00689                             mot_val[0] = mx;
00690                             mot_val[1] = my;
00691                         }
00692                     }
00693                 }
00694             }
00695         }
00696         s->mb_x= 0;
00697     }
00698 
00699     return mb_num;
00700 }
00701 
00706 static int mpeg4_decode_partition_b(MpegEncContext *s, int mb_count){
00707     int mb_num=0;
00708     static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
00709 
00710     s->mb_x= s->resync_mb_x;
00711     s->first_slice_line=1;
00712     for(s->mb_y= s->resync_mb_y; mb_num < mb_count; s->mb_y++){
00713         ff_init_block_index(s);
00714         for(; mb_num < mb_count && s->mb_x<s->mb_width; s->mb_x++){
00715             const int xy= s->mb_x + s->mb_y*s->mb_stride;
00716 
00717             mb_num++;
00718             ff_update_block_index(s);
00719             if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
00720                 s->first_slice_line=0;
00721 
00722             if(s->pict_type==AV_PICTURE_TYPE_I){
00723                 int ac_pred= get_bits1(&s->gb);
00724                 int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
00725                 if(cbpy<0){
00726                     av_log(s->avctx, AV_LOG_ERROR, "cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
00727                     return -1;
00728                 }
00729 
00730                 s->cbp_table[xy]|= cbpy<<2;
00731                 s->current_picture.f.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
00732             }else{ /* P || S_TYPE */
00733                 if (IS_INTRA(s->current_picture.f.mb_type[xy])) {
00734                     int dir=0,i;
00735                     int ac_pred = get_bits1(&s->gb);
00736                     int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
00737 
00738                     if(cbpy<0){
00739                         av_log(s->avctx, AV_LOG_ERROR, "I cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
00740                         return -1;
00741                     }
00742 
00743                     if(s->cbp_table[xy] & 8) {
00744                         ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
00745                     }
00746                     s->current_picture.f.qscale_table[xy] = s->qscale;
00747 
00748                     for(i=0; i<6; i++){
00749                         int dc_pred_dir;
00750                         int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
00751                         if(dc < 0){
00752                             av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
00753                             return -1;
00754                         }
00755                         dir<<=1;
00756                         if(dc_pred_dir) dir|=1;
00757                     }
00758                     s->cbp_table[xy]&= 3; //remove dquant
00759                     s->cbp_table[xy]|= cbpy<<2;
00760                     s->current_picture.f.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
00761                     s->pred_dir_table[xy]= dir;
00762                 } else if (IS_SKIP(s->current_picture.f.mb_type[xy])) {
00763                     s->current_picture.f.qscale_table[xy] = s->qscale;
00764                     s->cbp_table[xy]= 0;
00765                 }else{
00766                     int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
00767 
00768                     if(cbpy<0){
00769                         av_log(s->avctx, AV_LOG_ERROR, "P cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
00770                         return -1;
00771                     }
00772 
00773                     if(s->cbp_table[xy] & 8) {
00774                         ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
00775                     }
00776                     s->current_picture.f.qscale_table[xy] = s->qscale;
00777 
00778                     s->cbp_table[xy]&= 3; //remove dquant
00779                     s->cbp_table[xy]|= (cbpy^0xf)<<2;
00780                 }
00781             }
00782         }
00783         if(mb_num >= mb_count) return 0;
00784         s->mb_x= 0;
00785     }
00786     return 0;
00787 }
00788 
00793 int ff_mpeg4_decode_partitions(MpegEncContext *s)
00794 {
00795     int mb_num;
00796     const int part_a_error= s->pict_type==AV_PICTURE_TYPE_I ? (ER_DC_ERROR|ER_MV_ERROR) : ER_MV_ERROR;
00797     const int part_a_end  = s->pict_type==AV_PICTURE_TYPE_I ? (ER_DC_END  |ER_MV_END)   : ER_MV_END;
00798 
00799     mb_num= mpeg4_decode_partition_a(s);
00800     if(mb_num<0){
00801         ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
00802         return -1;
00803     }
00804 
00805     if(s->resync_mb_x + s->resync_mb_y*s->mb_width + mb_num > s->mb_num){
00806         av_log(s->avctx, AV_LOG_ERROR, "slice below monitor ...\n");
00807         ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
00808         return -1;
00809     }
00810 
00811     s->mb_num_left= mb_num;
00812 
00813     if(s->pict_type==AV_PICTURE_TYPE_I){
00814         while(show_bits(&s->gb, 9) == 1)
00815             skip_bits(&s->gb, 9);
00816         if(get_bits_long(&s->gb, 19)!=DC_MARKER){
00817             av_log(s->avctx, AV_LOG_ERROR, "marker missing after first I partition at %d %d\n", s->mb_x, s->mb_y);
00818             return -1;
00819         }
00820     }else{
00821         while(show_bits(&s->gb, 10) == 1)
00822             skip_bits(&s->gb, 10);
00823         if(get_bits(&s->gb, 17)!=MOTION_MARKER){
00824             av_log(s->avctx, AV_LOG_ERROR, "marker missing after first P partition at %d %d\n", s->mb_x, s->mb_y);
00825             return -1;
00826         }
00827     }
00828     ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, part_a_end);
00829 
00830     if( mpeg4_decode_partition_b(s, mb_num) < 0){
00831         if(s->pict_type==AV_PICTURE_TYPE_P)
00832             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_DC_ERROR);
00833         return -1;
00834     }else{
00835         if(s->pict_type==AV_PICTURE_TYPE_P)
00836             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_DC_END);
00837     }
00838 
00839     return 0;
00840 }
00841 
00846 static inline int mpeg4_decode_block(MpegEncContext * s, DCTELEM * block,
00847                               int n, int coded, int intra, int rvlc)
00848 {
00849     int level, i, last, run;
00850     int av_uninit(dc_pred_dir);
00851     RLTable * rl;
00852     RL_VLC_ELEM * rl_vlc;
00853     const uint8_t * scan_table;
00854     int qmul, qadd;
00855 
00856     //Note intra & rvlc should be optimized away if this is inlined
00857 
00858     if(intra) {
00859       if(s->use_intra_dc_vlc){
00860         /* DC coef */
00861         if(s->partitioned_frame){
00862             level = s->dc_val[0][ s->block_index[n] ];
00863             if(n<4) level= FASTDIV((level + (s->y_dc_scale>>1)), s->y_dc_scale);
00864             else    level= FASTDIV((level + (s->c_dc_scale>>1)), s->c_dc_scale);
00865             dc_pred_dir= (s->pred_dir_table[s->mb_x + s->mb_y*s->mb_stride]<<n)&32;
00866         }else{
00867             level = mpeg4_decode_dc(s, n, &dc_pred_dir);
00868             if (level < 0)
00869                 return -1;
00870         }
00871         block[0] = level;
00872         i = 0;
00873       }else{
00874             i = -1;
00875             ff_mpeg4_pred_dc(s, n, 0, &dc_pred_dir, 0);
00876       }
00877       if (!coded)
00878           goto not_coded;
00879 
00880       if(rvlc){
00881           rl = &ff_rvlc_rl_intra;
00882           rl_vlc = ff_rvlc_rl_intra.rl_vlc[0];
00883       }else{
00884           rl = &ff_mpeg4_rl_intra;
00885           rl_vlc = ff_mpeg4_rl_intra.rl_vlc[0];
00886       }
00887       if (s->ac_pred) {
00888           if (dc_pred_dir == 0)
00889               scan_table = s->intra_v_scantable.permutated; /* left */
00890           else
00891               scan_table = s->intra_h_scantable.permutated; /* top */
00892       } else {
00893             scan_table = s->intra_scantable.permutated;
00894       }
00895       qmul=1;
00896       qadd=0;
00897     } else {
00898         i = -1;
00899         if (!coded) {
00900             s->block_last_index[n] = i;
00901             return 0;
00902         }
00903         if(rvlc) rl = &ff_rvlc_rl_inter;
00904         else     rl = &ff_h263_rl_inter;
00905 
00906         scan_table = s->intra_scantable.permutated;
00907 
00908         if(s->mpeg_quant){
00909             qmul=1;
00910             qadd=0;
00911             if(rvlc){
00912                 rl_vlc = ff_rvlc_rl_inter.rl_vlc[0];
00913             }else{
00914                 rl_vlc = ff_h263_rl_inter.rl_vlc[0];
00915             }
00916         }else{
00917             qmul = s->qscale << 1;
00918             qadd = (s->qscale - 1) | 1;
00919             if(rvlc){
00920                 rl_vlc = ff_rvlc_rl_inter.rl_vlc[s->qscale];
00921             }else{
00922                 rl_vlc = ff_h263_rl_inter.rl_vlc[s->qscale];
00923             }
00924         }
00925     }
00926   {
00927     OPEN_READER(re, &s->gb);
00928     for(;;) {
00929         UPDATE_CACHE(re, &s->gb);
00930         GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
00931         if (level==0) {
00932           /* escape */
00933           if(rvlc){
00934                 if(SHOW_UBITS(re, &s->gb, 1)==0){
00935                     av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in rvlc esc\n");
00936                     return -1;
00937                 }; SKIP_CACHE(re, &s->gb, 1);
00938 
00939                 last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
00940                 run=   SHOW_UBITS(re, &s->gb, 6);
00941                 SKIP_COUNTER(re, &s->gb, 1+1+6);
00942                 UPDATE_CACHE(re, &s->gb);
00943 
00944                 if(SHOW_UBITS(re, &s->gb, 1)==0){
00945                     av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in rvlc esc\n");
00946                     return -1;
00947                 }; SKIP_CACHE(re, &s->gb, 1);
00948 
00949                 level= SHOW_UBITS(re, &s->gb, 11); SKIP_CACHE(re, &s->gb, 11);
00950 
00951                 if(SHOW_UBITS(re, &s->gb, 5)!=0x10){
00952                     av_log(s->avctx, AV_LOG_ERROR, "reverse esc missing\n");
00953                     return -1;
00954                 }; SKIP_CACHE(re, &s->gb, 5);
00955 
00956                 level=  level * qmul + qadd;
00957                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00958                 SKIP_COUNTER(re, &s->gb, 1+11+5+1);
00959 
00960                 i+= run + 1;
00961                 if(last) i+=192;
00962           }else{
00963             int cache;
00964             cache= GET_CACHE(re, &s->gb);
00965 
00966             if(IS_3IV1)
00967                 cache ^= 0xC0000000;
00968 
00969             if (cache&0x80000000) {
00970                 if (cache&0x40000000) {
00971                     /* third escape */
00972                     SKIP_CACHE(re, &s->gb, 2);
00973                     last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
00974                     run=   SHOW_UBITS(re, &s->gb, 6);
00975                     SKIP_COUNTER(re, &s->gb, 2+1+6);
00976                     UPDATE_CACHE(re, &s->gb);
00977 
00978                     if(IS_3IV1){
00979                         level= SHOW_SBITS(re, &s->gb, 12); LAST_SKIP_BITS(re, &s->gb, 12);
00980                     }else{
00981                         if(SHOW_UBITS(re, &s->gb, 1)==0){
00982                             av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in 3. esc\n");
00983                             return -1;
00984                         }; SKIP_CACHE(re, &s->gb, 1);
00985 
00986                         level= SHOW_SBITS(re, &s->gb, 12); SKIP_CACHE(re, &s->gb, 12);
00987 
00988                         if(SHOW_UBITS(re, &s->gb, 1)==0){
00989                             av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in 3. esc\n");
00990                             return -1;
00991                         }
00992 
00993                         SKIP_COUNTER(re, &s->gb, 1+12+1);
00994                     }
00995 
00996 #if 0
00997                     if(s->error_recognition >= FF_ER_COMPLIANT){
00998                         const int abs_level= FFABS(level);
00999                         if(abs_level<=MAX_LEVEL && run<=MAX_RUN){
01000                             const int run1= run - rl->max_run[last][abs_level] - 1;
01001                             if(abs_level <= rl->max_level[last][run]){
01002                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
01003                                 return -1;
01004                             }
01005                             if(s->error_recognition > FF_ER_COMPLIANT){
01006                                 if(abs_level <= rl->max_level[last][run]*2){
01007                                     av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
01008                                     return -1;
01009                                 }
01010                                 if(run1 >= 0 && abs_level <= rl->max_level[last][run1]){
01011                                     av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
01012                                     return -1;
01013                                 }
01014                             }
01015                         }
01016                     }
01017 #endif
01018                     if (level>0) level= level * qmul + qadd;
01019                     else         level= level * qmul - qadd;
01020 
01021                     if((unsigned)(level + 2048) > 4095){
01022                         if(s->err_recognition & (AV_EF_BITSTREAM|AV_EF_AGGRESSIVE)){
01023                             if(level > 2560 || level<-2560){
01024                                 av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc, qp=%d\n", s->qscale);
01025                                 return -1;
01026                             }
01027                         }
01028                         level= level<0 ? -2048 : 2047;
01029                     }
01030 
01031                     i+= run + 1;
01032                     if(last) i+=192;
01033                 } else {
01034                     /* second escape */
01035                     SKIP_BITS(re, &s->gb, 2);
01036                     GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
01037                     i+= run + rl->max_run[run>>7][level/qmul] +1; //FIXME opt indexing
01038                     level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
01039                     LAST_SKIP_BITS(re, &s->gb, 1);
01040                 }
01041             } else {
01042                 /* first escape */
01043                 SKIP_BITS(re, &s->gb, 1);
01044                 GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
01045                 i+= run;
01046                 level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
01047                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
01048                 LAST_SKIP_BITS(re, &s->gb, 1);
01049             }
01050           }
01051         } else {
01052             i+= run;
01053             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
01054             LAST_SKIP_BITS(re, &s->gb, 1);
01055         }
01056         if (i > 62){
01057             i-= 192;
01058             if(i&(~63)){
01059                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
01060                 return -1;
01061             }
01062 
01063             block[scan_table[i]] = level;
01064             break;
01065         }
01066 
01067         block[scan_table[i]] = level;
01068     }
01069     CLOSE_READER(re, &s->gb);
01070   }
01071  not_coded:
01072     if (intra) {
01073         if(!s->use_intra_dc_vlc){
01074             block[0] = ff_mpeg4_pred_dc(s, n, block[0], &dc_pred_dir, 0);
01075 
01076             i -= i>>31; //if(i == -1) i=0;
01077         }
01078 
01079         ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
01080         if (s->ac_pred) {
01081             i = 63; /* XXX: not optimal */
01082         }
01083     }
01084     s->block_last_index[n] = i;
01085     return 0;
01086 }
01087 
01092 static int mpeg4_decode_partitioned_mb(MpegEncContext *s, DCTELEM block[6][64])
01093 {
01094     int cbp, mb_type;
01095     const int xy= s->mb_x + s->mb_y*s->mb_stride;
01096 
01097     mb_type = s->current_picture.f.mb_type[xy];
01098     cbp = s->cbp_table[xy];
01099 
01100     s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
01101 
01102     if (s->current_picture.f.qscale_table[xy] != s->qscale) {
01103         ff_set_qscale(s, s->current_picture.f.qscale_table[xy]);
01104     }
01105 
01106     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type==AV_PICTURE_TYPE_S) {
01107         int i;
01108         for(i=0; i<4; i++){
01109             s->mv[0][i][0] = s->current_picture.f.motion_val[0][s->block_index[i]][0];
01110             s->mv[0][i][1] = s->current_picture.f.motion_val[0][s->block_index[i]][1];
01111         }
01112         s->mb_intra = IS_INTRA(mb_type);
01113 
01114         if (IS_SKIP(mb_type)) {
01115             /* skip mb */
01116             for(i=0;i<6;i++)
01117                 s->block_last_index[i] = -1;
01118             s->mv_dir = MV_DIR_FORWARD;
01119             s->mv_type = MV_TYPE_16X16;
01120             if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
01121                 s->mcsel=1;
01122                 s->mb_skipped = 0;
01123             }else{
01124                 s->mcsel=0;
01125                 s->mb_skipped = 1;
01126             }
01127         }else if(s->mb_intra){
01128             s->ac_pred = IS_ACPRED(s->current_picture.f.mb_type[xy]);
01129         }else if(!s->mb_intra){
01130 //            s->mcsel= 0; //FIXME do we need to init that
01131 
01132             s->mv_dir = MV_DIR_FORWARD;
01133             if (IS_8X8(mb_type)) {
01134                 s->mv_type = MV_TYPE_8X8;
01135             } else {
01136                 s->mv_type = MV_TYPE_16X16;
01137             }
01138         }
01139     } else { /* I-Frame */
01140         s->mb_intra = 1;
01141         s->ac_pred = IS_ACPRED(s->current_picture.f.mb_type[xy]);
01142     }
01143 
01144     if (!IS_SKIP(mb_type)) {
01145         int i;
01146         s->dsp.clear_blocks(s->block[0]);
01147         /* decode each block */
01148         for (i = 0; i < 6; i++) {
01149             if(mpeg4_decode_block(s, block[i], i, cbp&32, s->mb_intra, s->rvlc) < 0){
01150                 av_log(s->avctx, AV_LOG_ERROR, "texture corrupted at %d %d %d\n", s->mb_x, s->mb_y, s->mb_intra);
01151                 return -1;
01152             }
01153             cbp+=cbp;
01154         }
01155     }
01156 
01157     /* per-MB end of slice check */
01158 
01159     if(--s->mb_num_left <= 0){
01160         if(mpeg4_is_resync(s))
01161             return SLICE_END;
01162         else
01163             return SLICE_NOEND;
01164     }else{
01165         if(mpeg4_is_resync(s)){
01166             const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
01167             if(s->cbp_table[xy+delta])
01168                 return SLICE_END;
01169         }
01170         return SLICE_OK;
01171     }
01172 }
01173 
01174 static int mpeg4_decode_mb(MpegEncContext *s,
01175                       DCTELEM block[6][64])
01176 {
01177     int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
01178     int16_t *mot_val;
01179     static int8_t quant_tab[4] = { -1, -2, 1, 2 };
01180     const int xy= s->mb_x + s->mb_y * s->mb_stride;
01181 
01182     av_assert2(s->h263_pred);
01183 
01184     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type==AV_PICTURE_TYPE_S) {
01185         do{
01186             if (get_bits1(&s->gb)) {
01187                 /* skip mb */
01188                 s->mb_intra = 0;
01189                 for(i=0;i<6;i++)
01190                     s->block_last_index[i] = -1;
01191                 s->mv_dir = MV_DIR_FORWARD;
01192                 s->mv_type = MV_TYPE_16X16;
01193                 if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
01194                     s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
01195                     s->mcsel=1;
01196                     s->mv[0][0][0]= get_amv(s, 0);
01197                     s->mv[0][0][1]= get_amv(s, 1);
01198 
01199                     s->mb_skipped = 0;
01200                 }else{
01201                     s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
01202                     s->mcsel=0;
01203                     s->mv[0][0][0] = 0;
01204                     s->mv[0][0][1] = 0;
01205                     s->mb_skipped = 1;
01206                 }
01207                 goto end;
01208             }
01209             cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
01210             if (cbpc < 0){
01211                 av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
01212                 return -1;
01213             }
01214         }while(cbpc == 20);
01215 
01216         s->dsp.clear_blocks(s->block[0]);
01217         dquant = cbpc & 8;
01218         s->mb_intra = ((cbpc & 4) != 0);
01219         if (s->mb_intra) goto intra;
01220 
01221         if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
01222             s->mcsel= get_bits1(&s->gb);
01223         else s->mcsel= 0;
01224         cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1) ^ 0x0F;
01225 
01226         cbp = (cbpc & 3) | (cbpy << 2);
01227         if (dquant) {
01228             ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
01229         }
01230         if((!s->progressive_sequence) && (cbp || (s->workaround_bugs&FF_BUG_XVID_ILACE)))
01231             s->interlaced_dct= get_bits1(&s->gb);
01232 
01233         s->mv_dir = MV_DIR_FORWARD;
01234         if ((cbpc & 16) == 0) {
01235             if(s->mcsel){
01236                 s->current_picture.f.mb_type[xy] = MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
01237                 /* 16x16 global motion prediction */
01238                 s->mv_type = MV_TYPE_16X16;
01239                 mx= get_amv(s, 0);
01240                 my= get_amv(s, 1);
01241                 s->mv[0][0][0] = mx;
01242                 s->mv[0][0][1] = my;
01243             }else if((!s->progressive_sequence) && get_bits1(&s->gb)){
01244                 s->current_picture.f.mb_type[xy] = MB_TYPE_16x8 | MB_TYPE_L0 | MB_TYPE_INTERLACED;
01245                 /* 16x8 field motion prediction */
01246                 s->mv_type= MV_TYPE_FIELD;
01247 
01248                 s->field_select[0][0]= get_bits1(&s->gb);
01249                 s->field_select[0][1]= get_bits1(&s->gb);
01250 
01251                 ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
01252 
01253                 for(i=0; i<2; i++){
01254                     mx = ff_h263_decode_motion(s, pred_x, s->f_code);
01255                     if (mx >= 0xffff)
01256                         return -1;
01257 
01258                     my = ff_h263_decode_motion(s, pred_y/2, s->f_code);
01259                     if (my >= 0xffff)
01260                         return -1;
01261 
01262                     s->mv[0][i][0] = mx;
01263                     s->mv[0][i][1] = my;
01264                 }
01265             }else{
01266                 s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
01267                 /* 16x16 motion prediction */
01268                 s->mv_type = MV_TYPE_16X16;
01269                 ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
01270                 mx = ff_h263_decode_motion(s, pred_x, s->f_code);
01271 
01272                 if (mx >= 0xffff)
01273                     return -1;
01274 
01275                 my = ff_h263_decode_motion(s, pred_y, s->f_code);
01276 
01277                 if (my >= 0xffff)
01278                     return -1;
01279                 s->mv[0][0][0] = mx;
01280                 s->mv[0][0][1] = my;
01281             }
01282         } else {
01283             s->current_picture.f.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
01284             s->mv_type = MV_TYPE_8X8;
01285             for(i=0;i<4;i++) {
01286                 mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
01287                 mx = ff_h263_decode_motion(s, pred_x, s->f_code);
01288                 if (mx >= 0xffff)
01289                     return -1;
01290 
01291                 my = ff_h263_decode_motion(s, pred_y, s->f_code);
01292                 if (my >= 0xffff)
01293                     return -1;
01294                 s->mv[0][i][0] = mx;
01295                 s->mv[0][i][1] = my;
01296                 mot_val[0] = mx;
01297                 mot_val[1] = my;
01298             }
01299         }
01300     } else if(s->pict_type==AV_PICTURE_TYPE_B) {
01301         int modb1; // first bit of modb
01302         int modb2; // second bit of modb
01303         int mb_type;
01304 
01305         s->mb_intra = 0; //B-frames never contain intra blocks
01306         s->mcsel=0;      //     ...               true gmc blocks
01307 
01308         if(s->mb_x==0){
01309             for(i=0; i<2; i++){
01310                 s->last_mv[i][0][0]=
01311                 s->last_mv[i][0][1]=
01312                 s->last_mv[i][1][0]=
01313                 s->last_mv[i][1][1]= 0;
01314             }
01315 
01316             ff_thread_await_progress(&s->next_picture_ptr->f, s->mb_y, 0);
01317         }
01318 
01319         /* if we skipped it in the future P Frame than skip it now too */
01320         s->mb_skipped = s->next_picture.f.mbskip_table[s->mb_y * s->mb_stride + s->mb_x]; // Note, skiptab=0 if last was GMC
01321 
01322         if(s->mb_skipped){
01323                 /* skip mb */
01324             for(i=0;i<6;i++)
01325                 s->block_last_index[i] = -1;
01326 
01327             s->mv_dir = MV_DIR_FORWARD;
01328             s->mv_type = MV_TYPE_16X16;
01329             s->mv[0][0][0] = 0;
01330             s->mv[0][0][1] = 0;
01331             s->mv[1][0][0] = 0;
01332             s->mv[1][0][1] = 0;
01333             s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
01334             goto end;
01335         }
01336 
01337         modb1= get_bits1(&s->gb);
01338         if(modb1){
01339             mb_type= MB_TYPE_DIRECT2 | MB_TYPE_SKIP | MB_TYPE_L0L1; //like MB_TYPE_B_DIRECT but no vectors coded
01340             cbp=0;
01341         }else{
01342             modb2= get_bits1(&s->gb);
01343             mb_type= get_vlc2(&s->gb, mb_type_b_vlc.table, MB_TYPE_B_VLC_BITS, 1);
01344             if(mb_type<0){
01345                 av_log(s->avctx, AV_LOG_ERROR, "illegal MB_type\n");
01346                 return -1;
01347             }
01348             mb_type= mb_type_b_map[ mb_type ];
01349             if(modb2) cbp= 0;
01350             else{
01351                 s->dsp.clear_blocks(s->block[0]);
01352                 cbp= get_bits(&s->gb, 6);
01353             }
01354 
01355             if ((!IS_DIRECT(mb_type)) && cbp) {
01356                 if(get_bits1(&s->gb)){
01357                     ff_set_qscale(s, s->qscale + get_bits1(&s->gb)*4 - 2);
01358                 }
01359             }
01360 
01361             if(!s->progressive_sequence){
01362                 if(cbp)
01363                     s->interlaced_dct= get_bits1(&s->gb);
01364 
01365                 if(!IS_DIRECT(mb_type) && get_bits1(&s->gb)){
01366                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
01367                     mb_type &= ~MB_TYPE_16x16;
01368 
01369                     if(USES_LIST(mb_type, 0)){
01370                         s->field_select[0][0]= get_bits1(&s->gb);
01371                         s->field_select[0][1]= get_bits1(&s->gb);
01372                     }
01373                     if(USES_LIST(mb_type, 1)){
01374                         s->field_select[1][0]= get_bits1(&s->gb);
01375                         s->field_select[1][1]= get_bits1(&s->gb);
01376                     }
01377                 }
01378             }
01379 
01380             s->mv_dir = 0;
01381             if((mb_type & (MB_TYPE_DIRECT2|MB_TYPE_INTERLACED)) == 0){
01382                 s->mv_type= MV_TYPE_16X16;
01383 
01384                 if(USES_LIST(mb_type, 0)){
01385                     s->mv_dir = MV_DIR_FORWARD;
01386 
01387                     mx = ff_h263_decode_motion(s, s->last_mv[0][0][0], s->f_code);
01388                     my = ff_h263_decode_motion(s, s->last_mv[0][0][1], s->f_code);
01389                     s->last_mv[0][1][0]= s->last_mv[0][0][0]= s->mv[0][0][0] = mx;
01390                     s->last_mv[0][1][1]= s->last_mv[0][0][1]= s->mv[0][0][1] = my;
01391                 }
01392 
01393                 if(USES_LIST(mb_type, 1)){
01394                     s->mv_dir |= MV_DIR_BACKWARD;
01395 
01396                     mx = ff_h263_decode_motion(s, s->last_mv[1][0][0], s->b_code);
01397                     my = ff_h263_decode_motion(s, s->last_mv[1][0][1], s->b_code);
01398                     s->last_mv[1][1][0]= s->last_mv[1][0][0]= s->mv[1][0][0] = mx;
01399                     s->last_mv[1][1][1]= s->last_mv[1][0][1]= s->mv[1][0][1] = my;
01400                 }
01401             }else if(!IS_DIRECT(mb_type)){
01402                 s->mv_type= MV_TYPE_FIELD;
01403 
01404                 if(USES_LIST(mb_type, 0)){
01405                     s->mv_dir = MV_DIR_FORWARD;
01406 
01407                     for(i=0; i<2; i++){
01408                         mx = ff_h263_decode_motion(s, s->last_mv[0][i][0]  , s->f_code);
01409                         my = ff_h263_decode_motion(s, s->last_mv[0][i][1]/2, s->f_code);
01410                         s->last_mv[0][i][0]=  s->mv[0][i][0] = mx;
01411                         s->last_mv[0][i][1]= (s->mv[0][i][1] = my)*2;
01412                     }
01413                 }
01414 
01415                 if(USES_LIST(mb_type, 1)){
01416                     s->mv_dir |= MV_DIR_BACKWARD;
01417 
01418                     for(i=0; i<2; i++){
01419                         mx = ff_h263_decode_motion(s, s->last_mv[1][i][0]  , s->b_code);
01420                         my = ff_h263_decode_motion(s, s->last_mv[1][i][1]/2, s->b_code);
01421                         s->last_mv[1][i][0]=  s->mv[1][i][0] = mx;
01422                         s->last_mv[1][i][1]= (s->mv[1][i][1] = my)*2;
01423                     }
01424                 }
01425             }
01426         }
01427 
01428         if(IS_DIRECT(mb_type)){
01429             if(IS_SKIP(mb_type))
01430                 mx=my=0;
01431             else{
01432                 mx = ff_h263_decode_motion(s, 0, 1);
01433                 my = ff_h263_decode_motion(s, 0, 1);
01434             }
01435 
01436             s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT;
01437             mb_type |= ff_mpeg4_set_direct_mv(s, mx, my);
01438         }
01439         s->current_picture.f.mb_type[xy] = mb_type;
01440     } else { /* I-Frame */
01441         do{
01442             cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
01443             if (cbpc < 0){
01444                 av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
01445                 return -1;
01446             }
01447         }while(cbpc == 8);
01448 
01449         dquant = cbpc & 4;
01450         s->mb_intra = 1;
01451 intra:
01452         s->ac_pred = get_bits1(&s->gb);
01453         if(s->ac_pred)
01454             s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA | MB_TYPE_ACPRED;
01455         else
01456             s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
01457 
01458         cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
01459         if(cbpy<0){
01460             av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
01461             return -1;
01462         }
01463         cbp = (cbpc & 3) | (cbpy << 2);
01464 
01465         s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
01466 
01467         if (dquant) {
01468             ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
01469         }
01470 
01471         if(!s->progressive_sequence)
01472             s->interlaced_dct= get_bits1(&s->gb);
01473 
01474         s->dsp.clear_blocks(s->block[0]);
01475         /* decode each block */
01476         for (i = 0; i < 6; i++) {
01477             if (mpeg4_decode_block(s, block[i], i, cbp&32, 1, 0) < 0)
01478                 return -1;
01479             cbp+=cbp;
01480         }
01481         goto end;
01482     }
01483 
01484     /* decode each block */
01485     for (i = 0; i < 6; i++) {
01486         if (mpeg4_decode_block(s, block[i], i, cbp&32, 0, 0) < 0)
01487             return -1;
01488         cbp+=cbp;
01489     }
01490 end:
01491 
01492         /* per-MB end of slice check */
01493     if(s->codec_id==AV_CODEC_ID_MPEG4){
01494         int next= mpeg4_is_resync(s);
01495         if(next) {
01496             if        (s->mb_x + s->mb_y*s->mb_width + 1 >  next && (s->avctx->err_recognition & AV_EF_AGGRESSIVE)) {
01497                 return -1;
01498             } else if (s->mb_x + s->mb_y*s->mb_width + 1 >= next)
01499                 return SLICE_END;
01500 
01501             if(s->pict_type==AV_PICTURE_TYPE_B){
01502                 const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
01503                 ff_thread_await_progress(&s->next_picture_ptr->f,
01504                                         (s->mb_x + delta >= s->mb_width) ? FFMIN(s->mb_y+1, s->mb_height-1) : s->mb_y, 0);
01505                 if (s->next_picture.f.mbskip_table[xy + delta])
01506                     return SLICE_OK;
01507             }
01508 
01509             return SLICE_END;
01510         }
01511     }
01512 
01513     return SLICE_OK;
01514 }
01515 
01516 
01517 static int mpeg4_decode_gop_header(MpegEncContext * s, GetBitContext *gb){
01518     int hours, minutes, seconds;
01519 
01520     if(!show_bits(gb, 23)){
01521         av_log(s->avctx, AV_LOG_WARNING, "GOP header invalid\n");
01522         return -1;
01523     }
01524 
01525     hours= get_bits(gb, 5);
01526     minutes= get_bits(gb, 6);
01527     skip_bits1(gb);
01528     seconds= get_bits(gb, 6);
01529 
01530     s->time_base= seconds + 60*(minutes + 60*hours);
01531 
01532     skip_bits1(gb);
01533     skip_bits1(gb);
01534 
01535     return 0;
01536 }
01537 
01538 static int mpeg4_decode_profile_level(MpegEncContext * s, GetBitContext *gb){
01539 
01540     s->avctx->profile = get_bits(gb, 4);
01541     s->avctx->level   = get_bits(gb, 4);
01542 
01543     // for Simple profile, level 0
01544     if (s->avctx->profile == 0 && s->avctx->level == 8) {
01545         s->avctx->level = 0;
01546     }
01547 
01548     return 0;
01549 }
01550 
01551 static int decode_vol_header(MpegEncContext *s, GetBitContext *gb){
01552     int width, height, vo_ver_id;
01553 
01554     /* vol header */
01555     skip_bits(gb, 1); /* random access */
01556     s->vo_type= get_bits(gb, 8);
01557     if (get_bits1(gb) != 0) { /* is_ol_id */
01558         vo_ver_id = get_bits(gb, 4); /* vo_ver_id */
01559         skip_bits(gb, 3); /* vo_priority */
01560     } else {
01561         vo_ver_id = 1;
01562     }
01563     s->aspect_ratio_info= get_bits(gb, 4);
01564     if(s->aspect_ratio_info == FF_ASPECT_EXTENDED){
01565         s->avctx->sample_aspect_ratio.num= get_bits(gb, 8); // par_width
01566         s->avctx->sample_aspect_ratio.den= get_bits(gb, 8); // par_height
01567     }else{
01568         s->avctx->sample_aspect_ratio= ff_h263_pixel_aspect[s->aspect_ratio_info];
01569     }
01570 
01571     if ((s->vol_control_parameters=get_bits1(gb))) { /* vol control parameter */
01572         int chroma_format= get_bits(gb, 2);
01573         if(chroma_format!=CHROMA_420){
01574             av_log(s->avctx, AV_LOG_ERROR, "illegal chroma format\n");
01575         }
01576         s->low_delay= get_bits1(gb);
01577         if(get_bits1(gb)){ /* vbv parameters */
01578             get_bits(gb, 15);   /* first_half_bitrate */
01579             skip_bits1(gb);     /* marker */
01580             get_bits(gb, 15);   /* latter_half_bitrate */
01581             skip_bits1(gb);     /* marker */
01582             get_bits(gb, 15);   /* first_half_vbv_buffer_size */
01583             skip_bits1(gb);     /* marker */
01584             get_bits(gb, 3);    /* latter_half_vbv_buffer_size */
01585             get_bits(gb, 11);   /* first_half_vbv_occupancy */
01586             skip_bits1(gb);     /* marker */
01587             get_bits(gb, 15);   /* latter_half_vbv_occupancy */
01588             skip_bits1(gb);     /* marker */
01589         }
01590     }else{
01591         // set low delay flag only once the smartest? low delay detection won't be overridden
01592         if(s->picture_number==0)
01593             s->low_delay=0;
01594     }
01595 
01596     s->shape = get_bits(gb, 2); /* vol shape */
01597     if(s->shape != RECT_SHAPE) av_log(s->avctx, AV_LOG_ERROR, "only rectangular vol supported\n");
01598     if(s->shape == GRAY_SHAPE && vo_ver_id != 1){
01599         av_log(s->avctx, AV_LOG_ERROR, "Gray shape not supported\n");
01600         skip_bits(gb, 4);  //video_object_layer_shape_extension
01601     }
01602 
01603     check_marker(gb, "before time_increment_resolution");
01604 
01605     s->avctx->time_base.den = get_bits(gb, 16);
01606     if(!s->avctx->time_base.den){
01607         av_log(s->avctx, AV_LOG_ERROR, "time_base.den==0\n");
01608         s->avctx->time_base.num = 0;
01609         return -1;
01610     }
01611 
01612     s->time_increment_bits = av_log2(s->avctx->time_base.den - 1) + 1;
01613     if (s->time_increment_bits < 1)
01614         s->time_increment_bits = 1;
01615 
01616     check_marker(gb, "before fixed_vop_rate");
01617 
01618     if (get_bits1(gb) != 0) {   /* fixed_vop_rate  */
01619         s->avctx->time_base.num = get_bits(gb, s->time_increment_bits);
01620     }else
01621         s->avctx->time_base.num = 1;
01622 
01623     s->t_frame=0;
01624 
01625     if (s->shape != BIN_ONLY_SHAPE) {
01626         if (s->shape == RECT_SHAPE) {
01627             skip_bits1(gb);   /* marker */
01628             width = get_bits(gb, 13);
01629             skip_bits1(gb);   /* marker */
01630             height = get_bits(gb, 13);
01631             skip_bits1(gb);   /* marker */
01632             if(width && height && !(s->width && s->codec_tag == AV_RL32("MP4S"))){ /* they should be non zero but who knows ... */
01633                 if (s->width && s->height &&
01634                     (s->width != width || s->height != height))
01635                     s->context_reinit = 1;
01636                 s->width = width;
01637                 s->height = height;
01638             }
01639         }
01640 
01641         s->progressive_sequence=
01642         s->progressive_frame= get_bits1(gb)^1;
01643         s->interlaced_dct=0;
01644         if(!get_bits1(gb) && (s->avctx->debug & FF_DEBUG_PICT_INFO))
01645             av_log(s->avctx, AV_LOG_INFO, "MPEG4 OBMC not supported (very likely buggy encoder)\n");   /* OBMC Disable */
01646         if (vo_ver_id == 1) {
01647             s->vol_sprite_usage = get_bits1(gb); /* vol_sprite_usage */
01648         } else {
01649             s->vol_sprite_usage = get_bits(gb, 2); /* vol_sprite_usage */
01650         }
01651         if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "Static Sprites not supported\n");
01652         if(s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE){
01653             if(s->vol_sprite_usage==STATIC_SPRITE){
01654                 s->sprite_width = get_bits(gb, 13);
01655                 skip_bits1(gb); /* marker */
01656                 s->sprite_height= get_bits(gb, 13);
01657                 skip_bits1(gb); /* marker */
01658                 s->sprite_left  = get_bits(gb, 13);
01659                 skip_bits1(gb); /* marker */
01660                 s->sprite_top   = get_bits(gb, 13);
01661                 skip_bits1(gb); /* marker */
01662             }
01663             s->num_sprite_warping_points= get_bits(gb, 6);
01664             if(s->num_sprite_warping_points > 3){
01665                 av_log(s->avctx, AV_LOG_ERROR, "%d sprite_warping_points\n", s->num_sprite_warping_points);
01666                 s->num_sprite_warping_points= 0;
01667                 return -1;
01668             }
01669             s->sprite_warping_accuracy = get_bits(gb, 2);
01670             s->sprite_brightness_change= get_bits1(gb);
01671             if(s->vol_sprite_usage==STATIC_SPRITE)
01672                 s->low_latency_sprite= get_bits1(gb);
01673         }
01674         // FIXME sadct disable bit if verid!=1 && shape not rect
01675 
01676         if (get_bits1(gb) == 1) {   /* not_8_bit */
01677             s->quant_precision = get_bits(gb, 4); /* quant_precision */
01678             if(get_bits(gb, 4)!=8) av_log(s->avctx, AV_LOG_ERROR, "N-bit not supported\n"); /* bits_per_pixel */
01679             if(s->quant_precision!=5) av_log(s->avctx, AV_LOG_ERROR, "quant precision %d\n", s->quant_precision);
01680             if(s->quant_precision<3 || s->quant_precision>9) {
01681                 s->quant_precision = 5;
01682             }
01683         } else {
01684             s->quant_precision = 5;
01685         }
01686 
01687         // FIXME a bunch of grayscale shape things
01688 
01689         if((s->mpeg_quant=get_bits1(gb))){ /* vol_quant_type */
01690             int i, v;
01691 
01692             /* load default matrixes */
01693             for(i=0; i<64; i++){
01694                 int j= s->dsp.idct_permutation[i];
01695                 v= ff_mpeg4_default_intra_matrix[i];
01696                 s->intra_matrix[j]= v;
01697                 s->chroma_intra_matrix[j]= v;
01698 
01699                 v= ff_mpeg4_default_non_intra_matrix[i];
01700                 s->inter_matrix[j]= v;
01701                 s->chroma_inter_matrix[j]= v;
01702             }
01703 
01704             /* load custom intra matrix */
01705             if(get_bits1(gb)){
01706                 int last=0;
01707                 for(i=0; i<64; i++){
01708                     int j;
01709                     v= get_bits(gb, 8);
01710                     if(v==0) break;
01711 
01712                     last= v;
01713                     j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01714                     s->intra_matrix[j]= v;
01715                     s->chroma_intra_matrix[j]= v;
01716                 }
01717 
01718                 /* replicate last value */
01719                 for(; i<64; i++){
01720                     int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01721                     s->intra_matrix[j]= last;
01722                     s->chroma_intra_matrix[j]= last;
01723                 }
01724             }
01725 
01726             /* load custom non intra matrix */
01727             if(get_bits1(gb)){
01728                 int last=0;
01729                 for(i=0; i<64; i++){
01730                     int j;
01731                     v= get_bits(gb, 8);
01732                     if(v==0) break;
01733 
01734                     last= v;
01735                     j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01736                     s->inter_matrix[j]= v;
01737                     s->chroma_inter_matrix[j]= v;
01738                 }
01739 
01740                 /* replicate last value */
01741                 for(; i<64; i++){
01742                     int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01743                     s->inter_matrix[j]= last;
01744                     s->chroma_inter_matrix[j]= last;
01745                 }
01746             }
01747 
01748             // FIXME a bunch of grayscale shape things
01749         }
01750 
01751         if(vo_ver_id != 1)
01752              s->quarter_sample= get_bits1(gb);
01753         else s->quarter_sample=0;
01754 
01755         if(!get_bits1(gb)){
01756             int pos= get_bits_count(gb);
01757             int estimation_method= get_bits(gb, 2);
01758             if(estimation_method<2){
01759                 if(!get_bits1(gb)){
01760                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //opaque
01761                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //transparent
01762                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_cae
01763                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //inter_cae
01764                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //no_update
01765                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //upampling
01766                 }
01767                 if(!get_bits1(gb)){
01768                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_blocks
01769                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter_blocks
01770                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter4v_blocks
01771                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //not coded blocks
01772                 }
01773                 if(!check_marker(gb, "in complexity estimation part 1")){
01774                     skip_bits_long(gb, pos - get_bits_count(gb));
01775                     goto no_cplx_est;
01776                 }
01777                 if(!get_bits1(gb)){
01778                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_coeffs
01779                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_lines
01780                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //vlc_syms
01781                     s->cplx_estimation_trash_i += 4*get_bits1(gb); //vlc_bits
01782                 }
01783                 if(!get_bits1(gb)){
01784                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //apm
01785                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //npm
01786                     s->cplx_estimation_trash_b += 8*get_bits1(gb); //interpolate_mc_q
01787                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //forwback_mc_q
01788                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel2
01789                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel4
01790                 }
01791                 if(!check_marker(gb, "in complexity estimation part 2")){
01792                     skip_bits_long(gb, pos - get_bits_count(gb));
01793                     goto no_cplx_est;
01794                 }
01795                 if(estimation_method==1){
01796                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //sadct
01797                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //qpel
01798                 }
01799             }else
01800                 av_log(s->avctx, AV_LOG_ERROR, "Invalid Complexity estimation method %d\n", estimation_method);
01801         }else{
01802 no_cplx_est:
01803             s->cplx_estimation_trash_i=
01804             s->cplx_estimation_trash_p=
01805             s->cplx_estimation_trash_b= 0;
01806         }
01807 
01808         s->resync_marker= !get_bits1(gb); /* resync_marker_disabled */
01809 
01810         s->data_partitioning= get_bits1(gb);
01811         if(s->data_partitioning){
01812             s->rvlc= get_bits1(gb);
01813         }
01814 
01815         if(vo_ver_id != 1) {
01816             s->new_pred= get_bits1(gb);
01817             if(s->new_pred){
01818                 av_log(s->avctx, AV_LOG_ERROR, "new pred not supported\n");
01819                 skip_bits(gb, 2); /* requested upstream message type */
01820                 skip_bits1(gb); /* newpred segment type */
01821             }
01822             s->reduced_res_vop= get_bits1(gb);
01823             if(s->reduced_res_vop) av_log(s->avctx, AV_LOG_ERROR, "reduced resolution VOP not supported\n");
01824         }
01825         else{
01826             s->new_pred=0;
01827             s->reduced_res_vop= 0;
01828         }
01829 
01830         s->scalability= get_bits1(gb);
01831 
01832         if (s->scalability) {
01833             GetBitContext bak= *gb;
01834             int h_sampling_factor_n;
01835             int h_sampling_factor_m;
01836             int v_sampling_factor_n;
01837             int v_sampling_factor_m;
01838 
01839             s->hierachy_type= get_bits1(gb);
01840             skip_bits(gb, 4);  /* ref_layer_id */
01841             skip_bits1(gb);    /* ref_layer_sampling_dir */
01842             h_sampling_factor_n= get_bits(gb, 5);
01843             h_sampling_factor_m= get_bits(gb, 5);
01844             v_sampling_factor_n= get_bits(gb, 5);
01845             v_sampling_factor_m= get_bits(gb, 5);
01846             s->enhancement_type= get_bits1(gb);
01847 
01848             if(   h_sampling_factor_n==0 || h_sampling_factor_m==0
01849                || v_sampling_factor_n==0 || v_sampling_factor_m==0){
01850                 /* illegal scalability header (VERY broken encoder),
01851                  * trying to workaround */
01852                 s->scalability=0;
01853                 *gb= bak;
01854             }else
01855                 av_log(s->avctx, AV_LOG_ERROR, "scalability not supported\n");
01856 
01857             // bin shape stuff FIXME
01858         }
01859     }
01860 
01861     if(s->avctx->debug&FF_DEBUG_PICT_INFO) {
01862         av_log(s->avctx, AV_LOG_DEBUG, "tb %d/%d, tincrbits:%d, qp_prec:%d, ps:%d,  %s%s%s%s\n",
01863                s->avctx->time_base.num, s->avctx->time_base.den,
01864                s->time_increment_bits,
01865                s->quant_precision,
01866                s->progressive_sequence,
01867                s->scalability ? "scalability " :"" , s->quarter_sample ? "qpel " : "",
01868                s->data_partitioning ? "partition " : "", s->rvlc ? "rvlc " : ""
01869         );
01870     }
01871 
01872     return 0;
01873 }
01874 
01879 static int decode_user_data(MpegEncContext *s, GetBitContext *gb){
01880     char buf[256];
01881     int i;
01882     int e;
01883     int ver = 0, build = 0, ver2 = 0, ver3 = 0;
01884     char last;
01885 
01886     for(i=0; i<255 && get_bits_count(gb) < gb->size_in_bits; i++){
01887         if(show_bits(gb, 23) == 0) break;
01888         buf[i]= get_bits(gb, 8);
01889     }
01890     buf[i]=0;
01891 
01892     /* divx detection */
01893     e=sscanf(buf, "DivX%dBuild%d%c", &ver, &build, &last);
01894     if(e<2)
01895         e=sscanf(buf, "DivX%db%d%c", &ver, &build, &last);
01896     if(e>=2){
01897         s->divx_version= ver;
01898         s->divx_build= build;
01899         s->divx_packed= e==3 && last=='p';
01900         if(s->divx_packed && !s->showed_packed_warning) {
01901             av_log(s->avctx, AV_LOG_WARNING, "Invalid and inefficient vfw-avi packed B frames detected\n");
01902             s->showed_packed_warning=1;
01903         }
01904     }
01905 
01906     /* libavcodec detection */
01907     e=sscanf(buf, "FFmpe%*[^b]b%d", &build)+3;
01908     if(e!=4)
01909         e=sscanf(buf, "FFmpeg v%d.%d.%d / libavcodec build: %d", &ver, &ver2, &ver3, &build);
01910     if(e!=4){
01911         e=sscanf(buf, "Lavc%d.%d.%d", &ver, &ver2, &ver3)+1;
01912         if (e>1)
01913             build= (ver<<16) + (ver2<<8) + ver3;
01914     }
01915     if(e!=4){
01916         if(strcmp(buf, "ffmpeg")==0){
01917             s->lavc_build= 4600;
01918         }
01919     }
01920     if(e==4){
01921         s->lavc_build= build;
01922     }
01923 
01924     /* Xvid detection */
01925     e=sscanf(buf, "XviD%d", &build);
01926     if(e==1){
01927         s->xvid_build= build;
01928     }
01929 
01930     return 0;
01931 }
01932 
01933 static int decode_vop_header(MpegEncContext *s, GetBitContext *gb){
01934     int time_incr, time_increment;
01935 
01936     s->pict_type = get_bits(gb, 2) + AV_PICTURE_TYPE_I;        /* pict type: I = 0 , P = 1 */
01937     if(s->pict_type==AV_PICTURE_TYPE_B && s->low_delay && s->vol_control_parameters==0 && !(s->flags & CODEC_FLAG_LOW_DELAY)){
01938         av_log(s->avctx, AV_LOG_ERROR, "low_delay flag incorrectly, clearing it\n");
01939         s->low_delay=0;
01940     }
01941 
01942     s->partitioned_frame= s->data_partitioning && s->pict_type!=AV_PICTURE_TYPE_B;
01943     if(s->partitioned_frame)
01944         s->decode_mb= mpeg4_decode_partitioned_mb;
01945     else
01946         s->decode_mb= mpeg4_decode_mb;
01947 
01948     time_incr=0;
01949     while (get_bits1(gb) != 0)
01950         time_incr++;
01951 
01952     check_marker(gb, "before time_increment");
01953 
01954     if(s->time_increment_bits==0 || !(show_bits(gb, s->time_increment_bits+1)&1)){
01955         av_log(s->avctx, AV_LOG_ERROR, "hmm, seems the headers are not complete, trying to guess time_increment_bits\n");
01956 
01957         for(s->time_increment_bits=1 ;s->time_increment_bits<16; s->time_increment_bits++){
01958             if (    s->pict_type == AV_PICTURE_TYPE_P
01959                 || (s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE)) {
01960                 if((show_bits(gb, s->time_increment_bits+6)&0x37) == 0x30) break;
01961             }else
01962                 if((show_bits(gb, s->time_increment_bits+5)&0x1F) == 0x18) break;
01963         }
01964 
01965         av_log(s->avctx, AV_LOG_ERROR, "my guess is %d bits ;)\n",s->time_increment_bits);
01966     }
01967 
01968     if(IS_3IV1) time_increment= get_bits1(gb); //FIXME investigate further
01969     else time_increment= get_bits(gb, s->time_increment_bits);
01970 
01971     if(s->pict_type!=AV_PICTURE_TYPE_B){
01972         s->last_time_base= s->time_base;
01973         s->time_base+= time_incr;
01974         s->time= s->time_base*s->avctx->time_base.den + time_increment;
01975         if(s->workaround_bugs&FF_BUG_UMP4){
01976             if(s->time < s->last_non_b_time){
01977                 /* header is not mpeg-4-compatible, broken encoder,
01978                  * trying to workaround */
01979                 s->time_base++;
01980                 s->time+= s->avctx->time_base.den;
01981             }
01982         }
01983         s->pp_time= s->time - s->last_non_b_time;
01984         s->last_non_b_time= s->time;
01985     }else{
01986         s->time= (s->last_time_base + time_incr)*s->avctx->time_base.den + time_increment;
01987         s->pb_time= s->pp_time - (s->last_non_b_time - s->time);
01988         if(s->pp_time <=s->pb_time || s->pp_time <= s->pp_time - s->pb_time || s->pp_time<=0){
01989             /* messed up order, maybe after seeking? skipping current b-frame */
01990             return FRAME_SKIPPED;
01991         }
01992         ff_mpeg4_init_direct_mv(s);
01993 
01994         if(s->t_frame==0) s->t_frame= s->pb_time;
01995         if(s->t_frame==0) s->t_frame=1; // 1/0 protection
01996         s->pp_field_time= (  ROUNDED_DIV(s->last_non_b_time, s->t_frame)
01997                            - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
01998         s->pb_field_time= (  ROUNDED_DIV(s->time, s->t_frame)
01999                            - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
02000         if(!s->progressive_sequence){
02001             if(s->pp_field_time <= s->pb_field_time || s->pb_field_time <= 1)
02002                 return FRAME_SKIPPED;
02003         }
02004     }
02005 
02006     if(s->avctx->time_base.num)
02007         s->current_picture_ptr->f.pts = (s->time + s->avctx->time_base.num / 2) / s->avctx->time_base.num;
02008     else
02009         s->current_picture_ptr->f.pts = AV_NOPTS_VALUE;
02010     if(s->avctx->debug&FF_DEBUG_PTS)
02011         av_log(s->avctx, AV_LOG_DEBUG, "MPEG4 PTS: %"PRId64"\n",
02012                s->current_picture_ptr->f.pts);
02013 
02014     check_marker(gb, "before vop_coded");
02015 
02016     /* vop coded */
02017     if (get_bits1(gb) != 1){
02018         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
02019             av_log(s->avctx, AV_LOG_ERROR, "vop not coded\n");
02020         return FRAME_SKIPPED;
02021     }
02022     if (s->shape != BIN_ONLY_SHAPE && ( s->pict_type == AV_PICTURE_TYPE_P
02023                           || (s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE))) {
02024         /* rounding type for motion estimation */
02025         s->no_rounding = get_bits1(gb);
02026     } else {
02027         s->no_rounding = 0;
02028     }
02029 //FIXME reduced res stuff
02030 
02031      if (s->shape != RECT_SHAPE) {
02032          if (s->vol_sprite_usage != 1 || s->pict_type != AV_PICTURE_TYPE_I) {
02033              skip_bits(gb, 13); /* width */
02034              skip_bits1(gb);   /* marker */
02035              skip_bits(gb, 13); /* height */
02036              skip_bits1(gb);   /* marker */
02037              skip_bits(gb, 13); /* hor_spat_ref */
02038              skip_bits1(gb);   /* marker */
02039              skip_bits(gb, 13); /* ver_spat_ref */
02040          }
02041          skip_bits1(gb); /* change_CR_disable */
02042 
02043          if (get_bits1(gb) != 0) {
02044              skip_bits(gb, 8); /* constant_alpha_value */
02045          }
02046      }
02047 //FIXME complexity estimation stuff
02048 
02049      if (s->shape != BIN_ONLY_SHAPE) {
02050          skip_bits_long(gb, s->cplx_estimation_trash_i);
02051          if(s->pict_type != AV_PICTURE_TYPE_I)
02052             skip_bits_long(gb, s->cplx_estimation_trash_p);
02053          if(s->pict_type == AV_PICTURE_TYPE_B)
02054             skip_bits_long(gb, s->cplx_estimation_trash_b);
02055 
02056          if(get_bits_left(gb) < 3) {
02057              av_log(s->avctx, AV_LOG_ERROR, "Header truncated\n");
02058              return -1;
02059          }
02060          s->intra_dc_threshold= ff_mpeg4_dc_threshold[ get_bits(gb, 3) ];
02061          if(!s->progressive_sequence){
02062              s->top_field_first= get_bits1(gb);
02063              s->alternate_scan= get_bits1(gb);
02064          }else
02065              s->alternate_scan= 0;
02066      }
02067 
02068      if(s->alternate_scan){
02069          ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
02070          ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
02071          ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
02072          ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
02073      } else{
02074          ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
02075          ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
02076          ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
02077          ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
02078      }
02079 
02080      if(s->pict_type == AV_PICTURE_TYPE_S && (s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE)){
02081          if(mpeg4_decode_sprite_trajectory(s, gb) < 0)
02082              return -1;
02083          if(s->sprite_brightness_change) av_log(s->avctx, AV_LOG_ERROR, "sprite_brightness_change not supported\n");
02084          if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "static sprite not supported\n");
02085      }
02086 
02087      if (s->shape != BIN_ONLY_SHAPE) {
02088          s->chroma_qscale= s->qscale = get_bits(gb, s->quant_precision);
02089          if(s->qscale==0){
02090              av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (qscale=0)\n");
02091              return -1; // makes no sense to continue, as there is nothing left from the image then
02092          }
02093 
02094          if (s->pict_type != AV_PICTURE_TYPE_I) {
02095              s->f_code = get_bits(gb, 3);       /* fcode_for */
02096              if(s->f_code==0){
02097                  av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (f_code=0)\n");
02098                  s->f_code=1;
02099                  return -1; // makes no sense to continue, as the MV decoding will break very quickly
02100              }
02101          }else
02102              s->f_code=1;
02103 
02104          if (s->pict_type == AV_PICTURE_TYPE_B) {
02105              s->b_code = get_bits(gb, 3);
02106              if(s->b_code==0){
02107                  av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (b_code=0)\n");
02108                  s->b_code=1;
02109                  return -1; // makes no sense to continue, as the MV decoding will break very quickly
02110              }
02111          }else
02112              s->b_code=1;
02113 
02114          if(s->avctx->debug&FF_DEBUG_PICT_INFO){
02115              av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%d,%d %s size:%d pro:%d alt:%d top:%d %spel part:%d resync:%d w:%d a:%d rnd:%d vot:%d%s dc:%d ce:%d/%d/%d time:%"PRId64" tincr:%d\n",
02116                  s->qscale, s->f_code, s->b_code,
02117                  s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
02118                  gb->size_in_bits,s->progressive_sequence, s->alternate_scan, s->top_field_first,
02119                  s->quarter_sample ? "q" : "h", s->data_partitioning, s->resync_marker, s->num_sprite_warping_points,
02120                  s->sprite_warping_accuracy, 1-s->no_rounding, s->vo_type, s->vol_control_parameters ? " VOLC" : " ", s->intra_dc_threshold,
02121                  s->cplx_estimation_trash_i, s->cplx_estimation_trash_p, s->cplx_estimation_trash_b,
02122                  s->time,
02123                  time_increment
02124                    );
02125          }
02126 
02127          if(!s->scalability){
02128              if (s->shape!=RECT_SHAPE && s->pict_type!=AV_PICTURE_TYPE_I) {
02129                  skip_bits1(gb); // vop shape coding type
02130              }
02131          }else{
02132              if(s->enhancement_type){
02133                  int load_backward_shape= get_bits1(gb);
02134                  if(load_backward_shape){
02135                      av_log(s->avctx, AV_LOG_ERROR, "load backward shape isn't supported\n");
02136                  }
02137              }
02138              skip_bits(gb, 2); //ref_select_code
02139          }
02140      }
02141      /* detect buggy encoders which don't set the low_delay flag (divx4/xvid/opendivx)*/
02142      // note we cannot detect divx5 without b-frames easily (although it's buggy too)
02143      if(s->vo_type==0 && s->vol_control_parameters==0 && s->divx_version==-1 && s->picture_number==0){
02144          av_log(s->avctx, AV_LOG_WARNING, "looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
02145          s->low_delay=1;
02146      }
02147 
02148      s->picture_number++; // better than pic number==0 always ;)
02149 
02150      s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table; //FIXME add short header support
02151      s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;
02152 
02153      if(s->workaround_bugs&FF_BUG_EDGE){
02154          s->h_edge_pos= s->width;
02155          s->v_edge_pos= s->height;
02156      }
02157      return 0;
02158 }
02159 
02166 int ff_mpeg4_decode_picture_header(MpegEncContext * s, GetBitContext *gb)
02167 {
02168     unsigned startcode, v;
02169 
02170     /* search next start code */
02171     align_get_bits(gb);
02172 
02173     if(s->codec_tag == AV_RL32("WV1F") && show_bits(gb, 24) == 0x575630){
02174         skip_bits(gb, 24);
02175         if(get_bits(gb, 8) == 0xF0)
02176             goto end;
02177     }
02178 
02179     startcode = 0xff;
02180     for(;;) {
02181         if(get_bits_count(gb) >= gb->size_in_bits){
02182             if(gb->size_in_bits==8 && (s->divx_version>=0 || s->xvid_build>=0) || s->codec_tag == AV_RL32("QMP4")){
02183                 av_log(s->avctx, AV_LOG_VERBOSE, "frame skip %d\n", gb->size_in_bits);
02184                 return FRAME_SKIPPED; //divx bug
02185             }else
02186                 return -1; //end of stream
02187         }
02188 
02189         /* use the bits after the test */
02190         v = get_bits(gb, 8);
02191         startcode = ((startcode << 8) | v) & 0xffffffff;
02192 
02193         if((startcode&0xFFFFFF00) != 0x100)
02194             continue; //no startcode
02195 
02196         if(s->avctx->debug&FF_DEBUG_STARTCODE){
02197             av_log(s->avctx, AV_LOG_DEBUG, "startcode: %3X ", startcode);
02198             if     (startcode<=0x11F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Start");
02199             else if(startcode<=0x12F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Layer Start");
02200             else if(startcode<=0x13F) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
02201             else if(startcode<=0x15F) av_log(s->avctx, AV_LOG_DEBUG, "FGS bp start");
02202             else if(startcode<=0x1AF) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
02203             else if(startcode==0x1B0) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq Start");
02204             else if(startcode==0x1B1) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq End");
02205             else if(startcode==0x1B2) av_log(s->avctx, AV_LOG_DEBUG, "User Data");
02206             else if(startcode==0x1B3) av_log(s->avctx, AV_LOG_DEBUG, "Group of VOP start");
02207             else if(startcode==0x1B4) av_log(s->avctx, AV_LOG_DEBUG, "Video Session Error");
02208             else if(startcode==0x1B5) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Start");
02209             else if(startcode==0x1B6) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Plane start");
02210             else if(startcode==0x1B7) av_log(s->avctx, AV_LOG_DEBUG, "slice start");
02211             else if(startcode==0x1B8) av_log(s->avctx, AV_LOG_DEBUG, "extension start");
02212             else if(startcode==0x1B9) av_log(s->avctx, AV_LOG_DEBUG, "fgs start");
02213             else if(startcode==0x1BA) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object start");
02214             else if(startcode==0x1BB) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object Plane start");
02215             else if(startcode==0x1BC) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object start");
02216             else if(startcode==0x1BD) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object Plane start");
02217             else if(startcode==0x1BE) av_log(s->avctx, AV_LOG_DEBUG, "Still Texture Object start");
02218             else if(startcode==0x1BF) av_log(s->avctx, AV_LOG_DEBUG, "Texture Spatial Layer start");
02219             else if(startcode==0x1C0) av_log(s->avctx, AV_LOG_DEBUG, "Texture SNR Layer start");
02220             else if(startcode==0x1C1) av_log(s->avctx, AV_LOG_DEBUG, "Texture Tile start");
02221             else if(startcode==0x1C2) av_log(s->avctx, AV_LOG_DEBUG, "Texture Shape Layer start");
02222             else if(startcode==0x1C3) av_log(s->avctx, AV_LOG_DEBUG, "stuffing start");
02223             else if(startcode<=0x1C5) av_log(s->avctx, AV_LOG_DEBUG, "reserved");
02224             else if(startcode<=0x1FF) av_log(s->avctx, AV_LOG_DEBUG, "System start");
02225             av_log(s->avctx, AV_LOG_DEBUG, " at %d\n", get_bits_count(gb));
02226         }
02227 
02228         if(startcode >= 0x120 && startcode <= 0x12F){
02229             if(decode_vol_header(s, gb) < 0)
02230                 return -1;
02231         }
02232         else if(startcode == USER_DATA_STARTCODE){
02233             decode_user_data(s, gb);
02234         }
02235         else if(startcode == GOP_STARTCODE){
02236             mpeg4_decode_gop_header(s, gb);
02237         }
02238         else if(startcode == VOS_STARTCODE){
02239             mpeg4_decode_profile_level(s, gb);
02240         }
02241         else if(startcode == VOP_STARTCODE){
02242             break;
02243         }
02244 
02245         align_get_bits(gb);
02246         startcode = 0xff;
02247     }
02248 end:
02249     if(s->flags& CODEC_FLAG_LOW_DELAY)
02250         s->low_delay=1;
02251     s->avctx->has_b_frames= !s->low_delay;
02252     return decode_vop_header(s, gb);
02253 }
02254 
02255 static av_cold int decode_init(AVCodecContext *avctx)
02256 {
02257     MpegEncContext *s = avctx->priv_data;
02258     int ret;
02259     static int done = 0;
02260 
02261     s->divx_version=
02262     s->divx_build=
02263     s->xvid_build=
02264     s->lavc_build= -1;
02265 
02266     if((ret=ff_h263_decode_init(avctx)) < 0)
02267         return ret;
02268 
02269     if (!done) {
02270         done = 1;
02271 
02272         ff_init_rl(&ff_mpeg4_rl_intra, ff_mpeg4_static_rl_table_store[0]);
02273         ff_init_rl(&ff_rvlc_rl_inter, ff_mpeg4_static_rl_table_store[1]);
02274         ff_init_rl(&ff_rvlc_rl_intra, ff_mpeg4_static_rl_table_store[2]);
02275         INIT_VLC_RL(ff_mpeg4_rl_intra, 554);
02276         INIT_VLC_RL(ff_rvlc_rl_inter, 1072);
02277         INIT_VLC_RL(ff_rvlc_rl_intra, 1072);
02278         INIT_VLC_STATIC(&dc_lum, DC_VLC_BITS, 10 /* 13 */,
02279                  &ff_mpeg4_DCtab_lum[0][1], 2, 1,
02280                  &ff_mpeg4_DCtab_lum[0][0], 2, 1, 512);
02281         INIT_VLC_STATIC(&dc_chrom, DC_VLC_BITS, 10 /* 13 */,
02282                  &ff_mpeg4_DCtab_chrom[0][1], 2, 1,
02283                  &ff_mpeg4_DCtab_chrom[0][0], 2, 1, 512);
02284         INIT_VLC_STATIC(&sprite_trajectory, SPRITE_TRAJ_VLC_BITS, 15,
02285                  &ff_sprite_trajectory_tab[0][1], 4, 2,
02286                  &ff_sprite_trajectory_tab[0][0], 4, 2, 128);
02287         INIT_VLC_STATIC(&mb_type_b_vlc, MB_TYPE_B_VLC_BITS, 4,
02288                  &ff_mb_type_b_tab[0][1], 2, 1,
02289                  &ff_mb_type_b_tab[0][0], 2, 1, 16);
02290     }
02291 
02292     s->h263_pred = 1;
02293     s->low_delay = 0; //default, might be overridden in the vol header during header parsing
02294     s->decode_mb= mpeg4_decode_mb;
02295     s->time_increment_bits = 4; /* default value for broken headers */
02296     avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
02297 
02298     return 0;
02299 }
02300 
02301 static const AVProfile mpeg4_video_profiles[] = {
02302     { FF_PROFILE_MPEG4_SIMPLE,                    "Simple Profile" },
02303     { FF_PROFILE_MPEG4_SIMPLE_SCALABLE,           "Simple Scalable Profile" },
02304     { FF_PROFILE_MPEG4_CORE,                      "Core Profile" },
02305     { FF_PROFILE_MPEG4_MAIN,                      "Main Profile" },
02306     { FF_PROFILE_MPEG4_N_BIT,                     "N-bit Profile" },
02307     { FF_PROFILE_MPEG4_SCALABLE_TEXTURE,          "Scalable Texture Profile" },
02308     { FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION,     "Simple Face Animation Profile" },
02309     { FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE,    "Basic Animated Texture Profile" },
02310     { FF_PROFILE_MPEG4_HYBRID,                    "Hybrid Profile" },
02311     { FF_PROFILE_MPEG4_ADVANCED_REAL_TIME,        "Advanced Real Time Simple Profile" },
02312     { FF_PROFILE_MPEG4_CORE_SCALABLE,             "Code Scalable Profile" },
02313     { FF_PROFILE_MPEG4_ADVANCED_CODING,           "Advanced Coding Profile" },
02314     { FF_PROFILE_MPEG4_ADVANCED_CORE,             "Advanced Core Profile" },
02315     { FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE, "Advanced Scalable Texture Profile" },
02316     { FF_PROFILE_MPEG4_SIMPLE_STUDIO,             "Simple Studio Profile" },
02317     { FF_PROFILE_MPEG4_ADVANCED_SIMPLE,           "Advanced Simple Profile" },
02318     { FF_PROFILE_UNKNOWN },
02319 };
02320 
02321 static const AVOption mpeg4_options[] = {
02322     {"quarter_sample", "1/4 subpel MC", offsetof(MpegEncContext, quarter_sample), FF_OPT_TYPE_INT, {.dbl = 0}, 0, 1, 0},
02323     {"divx_packed", "divx style packed b frames", offsetof(MpegEncContext, divx_packed), FF_OPT_TYPE_INT, {.dbl = 0}, 0, 1, 0},
02324     {NULL}
02325 };
02326 
02327 static const AVClass mpeg4_class = {
02328     "MPEG4 Video Decoder",
02329     av_default_item_name,
02330     mpeg4_options,
02331     LIBAVUTIL_VERSION_INT,
02332 };
02333 
02334 static const AVClass mpeg4_vdpau_class = {
02335     "MPEG4 Video VDPAU Decoder",
02336     av_default_item_name,
02337     mpeg4_options,
02338     LIBAVUTIL_VERSION_INT,
02339 };
02340 
02341 AVCodec ff_mpeg4_decoder = {
02342     .name                  = "mpeg4",
02343     .type                  = AVMEDIA_TYPE_VIDEO,
02344     .id                    = AV_CODEC_ID_MPEG4,
02345     .priv_data_size        = sizeof(MpegEncContext),
02346     .init                  = decode_init,
02347     .close                 = ff_h263_decode_end,
02348     .decode                = ff_h263_decode_frame,
02349     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
02350                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
02351                              CODEC_CAP_FRAME_THREADS,
02352     .flush                 = ff_mpeg_flush,
02353     .max_lowres            = 3,
02354     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
02355     .pix_fmts              = ff_hwaccel_pixfmt_list_420,
02356     .profiles              = NULL_IF_CONFIG_SMALL(mpeg4_video_profiles),
02357     .update_thread_context = ONLY_IF_THREADS_ENABLED(ff_mpeg_update_thread_context),
02358     .priv_class = &mpeg4_class,
02359 };
02360 
02361 
02362 #if CONFIG_MPEG4_VDPAU_DECODER
02363 AVCodec ff_mpeg4_vdpau_decoder = {
02364     .name           = "mpeg4_vdpau",
02365     .type           = AVMEDIA_TYPE_VIDEO,
02366     .id             = AV_CODEC_ID_MPEG4,
02367     .priv_data_size = sizeof(MpegEncContext),
02368     .init           = decode_init,
02369     .close          = ff_h263_decode_end,
02370     .decode         = ff_h263_decode_frame,
02371     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
02372                       CODEC_CAP_HWACCEL_VDPAU,
02373     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 (VDPAU)"),
02374     .pix_fmts       = (const enum PixelFormat[]){ PIX_FMT_VDPAU_MPEG4,
02375                                                   PIX_FMT_NONE },
02376     .priv_class     = &mpeg4_vdpau_class,
02377 };
02378 #endif