FFmpeg: libavcodec/roqvideodec.c Source File

00001 /*
00002  * Copyright (C) 2003 the ffmpeg project
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00028 #include "avcodec.h"
00029 #include "bytestream.h"
00030 #include "roqvideo.h"
00031 
00032 static void roqvideo_decode_frame(RoqContext *ri)
00033 {
00034     unsigned int chunk_id = 0, chunk_arg = 0;
00035     unsigned long chunk_size = 0;
00036     int i, j, k, nv1, nv2, vqflg = 0, vqflg_pos = -1;
00037     int vqid, xpos, ypos, xp, yp, x, y, mx, my;
00038     int frame_stats[2][4] = {{0},{0}};
00039     roq_qcell *qcell;
00040     int64_t chunk_start;
00041 
00042     while (bytestream2_get_bytes_left(&ri->gb) >= 8) {
00043         chunk_id   = bytestream2_get_le16(&ri->gb);
00044         chunk_size = bytestream2_get_le32(&ri->gb);
00045         chunk_arg  = bytestream2_get_le16(&ri->gb);
00046 
00047         if(chunk_id == RoQ_QUAD_VQ)
00048             break;
00049         if(chunk_id == RoQ_QUAD_CODEBOOK) {
00050             if((nv1 = chunk_arg >> 8) == 0)
00051                 nv1 = 256;
00052             if((nv2 = chunk_arg & 0xff) == 0 && nv1 * 6 < chunk_size)
00053                 nv2 = 256;
00054             for(i = 0; i < nv1; i++) {
00055                 ri->cb2x2[i].y[0] = bytestream2_get_byte(&ri->gb);
00056                 ri->cb2x2[i].y[1] = bytestream2_get_byte(&ri->gb);
00057                 ri->cb2x2[i].y[2] = bytestream2_get_byte(&ri->gb);
00058                 ri->cb2x2[i].y[3] = bytestream2_get_byte(&ri->gb);
00059                 ri->cb2x2[i].u    = bytestream2_get_byte(&ri->gb);
00060                 ri->cb2x2[i].v    = bytestream2_get_byte(&ri->gb);
00061             }
00062             for(i = 0; i < nv2; i++)
00063                 for(j = 0; j < 4; j++)
00064                     ri->cb4x4[i].idx[j] = bytestream2_get_byte(&ri->gb);
00065         }
00066     }
00067 
00068     chunk_start = bytestream2_tell(&ri->gb);
00069     xpos = ypos = 0;
00070 
00071     if (chunk_size > bytestream2_get_bytes_left(&ri->gb)) {
00072         av_log(ri->avctx, AV_LOG_ERROR, "Chunk does not fit in input buffer\n");
00073         chunk_size = bytestream2_get_bytes_left(&ri->gb);
00074     }
00075 
00076     while (bytestream2_tell(&ri->gb) < chunk_start + chunk_size) {
00077         for (yp = ypos; yp < ypos + 16; yp += 8)
00078             for (xp = xpos; xp < xpos + 16; xp += 8) {
00079                 if (bytestream2_tell(&ri->gb) >= chunk_start + chunk_size) {
00080                     av_log(ri->avctx, AV_LOG_ERROR, "Input buffer too small\n");
00081                     return;
00082                 }
00083                 if (vqflg_pos < 0) {
00084                     vqflg = bytestream2_get_le16(&ri->gb);
00085                     vqflg_pos = 7;
00086                 }
00087                 vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
00088                 frame_stats[0][vqid]++;
00089                 vqflg_pos--;
00090 
00091                 switch(vqid) {
00092                 case RoQ_ID_MOT:
00093                     break;
00094                 case RoQ_ID_FCC: {
00095                     int byte = bytestream2_get_byte(&ri->gb);
00096                     mx = 8 - (byte >> 4) - ((signed char) (chunk_arg >> 8));
00097                     my = 8 - (byte & 0xf) - ((signed char) chunk_arg);
00098                     ff_apply_motion_8x8(ri, xp, yp, mx, my);
00099                     break;
00100                 }
00101                 case RoQ_ID_SLD:
00102                     qcell = ri->cb4x4 + bytestream2_get_byte(&ri->gb);
00103                     ff_apply_vector_4x4(ri, xp,     yp,     ri->cb2x2 + qcell->idx[0]);
00104                     ff_apply_vector_4x4(ri, xp + 4, yp,     ri->cb2x2 + qcell->idx[1]);
00105                     ff_apply_vector_4x4(ri, xp,     yp + 4, ri->cb2x2 + qcell->idx[2]);
00106                     ff_apply_vector_4x4(ri, xp + 4, yp + 4, ri->cb2x2 + qcell->idx[3]);
00107                     break;
00108                 case RoQ_ID_CCC:
00109                     for (k = 0; k < 4; k++) {
00110                         x = xp; y = yp;
00111                         if(k & 0x01) x += 4;
00112                         if(k & 0x02) y += 4;
00113 
00114                         if (bytestream2_tell(&ri->gb) >= chunk_start + chunk_size) {
00115                             av_log(ri->avctx, AV_LOG_ERROR, "Input buffer too small\n");
00116                             return;
00117                         }
00118                         if (vqflg_pos < 0) {
00119                             vqflg = bytestream2_get_le16(&ri->gb);
00120                             vqflg_pos = 7;
00121                         }
00122                         vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
00123                         frame_stats[1][vqid]++;
00124                         vqflg_pos--;
00125                         switch(vqid) {
00126                         case RoQ_ID_MOT:
00127                             break;
00128                         case RoQ_ID_FCC: {
00129                             int byte = bytestream2_get_byte(&ri->gb);
00130                             mx = 8 - (byte >> 4) - ((signed char) (chunk_arg >> 8));
00131                             my = 8 - (byte & 0xf) - ((signed char) chunk_arg);
00132                             ff_apply_motion_4x4(ri, x, y, mx, my);
00133                             break;
00134                         }
00135                         case RoQ_ID_SLD:
00136                             qcell = ri->cb4x4 + bytestream2_get_byte(&ri->gb);
00137                             ff_apply_vector_2x2(ri, x,     y,     ri->cb2x2 + qcell->idx[0]);
00138                             ff_apply_vector_2x2(ri, x + 2, y,     ri->cb2x2 + qcell->idx[1]);
00139                             ff_apply_vector_2x2(ri, x,     y + 2, ri->cb2x2 + qcell->idx[2]);
00140                             ff_apply_vector_2x2(ri, x + 2, y + 2, ri->cb2x2 + qcell->idx[3]);
00141                             break;
00142                         case RoQ_ID_CCC:
00143                             ff_apply_vector_2x2(ri, x,     y,     ri->cb2x2 + bytestream2_get_byte(&ri->gb));
00144                             ff_apply_vector_2x2(ri, x + 2, y,     ri->cb2x2 + bytestream2_get_byte(&ri->gb));
00145                             ff_apply_vector_2x2(ri, x,     y + 2, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
00146                             ff_apply_vector_2x2(ri, x + 2, y + 2, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
00147                             break;
00148                         }
00149                     }
00150                     break;
00151                 default:
00152                     av_log(ri->avctx, AV_LOG_ERROR, "Unknown vq code: %d\n", vqid);
00153             }
00154         }
00155 
00156         xpos += 16;
00157         if (xpos >= ri->width) {
00158             xpos -= ri->width;
00159             ypos += 16;
00160         }
00161         if(ypos >= ri->height)
00162             break;
00163     }
00164 }
00165 
00166 
00167 static av_cold int roq_decode_init(AVCodecContext *avctx)
00168 {
00169     RoqContext *s = avctx->priv_data;
00170 
00171     s->avctx = avctx;
00172     s->width = avctx->width;
00173     s->height = avctx->height;
00174     avcodec_get_frame_defaults(&s->frames[0]);
00175     avcodec_get_frame_defaults(&s->frames[1]);
00176     s->last_frame    = &s->frames[0];
00177     s->current_frame = &s->frames[1];
00178     avctx->pix_fmt = PIX_FMT_YUV444P;
00179 
00180     return 0;
00181 }
00182 
00183 static int roq_decode_frame(AVCodecContext *avctx,
00184                             void *data, int *data_size,
00185                             AVPacket *avpkt)
00186 {
00187     const uint8_t *buf = avpkt->data;
00188     int buf_size = avpkt->size;
00189     RoqContext *s = avctx->priv_data;
00190     int copy= !s->current_frame->data[0];
00191     int ret;
00192 
00193     s->current_frame->reference = 3;
00194     if ((ret = avctx->reget_buffer(avctx, s->current_frame)) < 0) {
00195         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
00196         return ret;
00197     }
00198 
00199     if(copy)
00200         av_picture_copy((AVPicture*)s->current_frame, (AVPicture*)s->last_frame,
00201                         avctx->pix_fmt, avctx->width, avctx->height);
00202 
00203     bytestream2_init(&s->gb, buf, buf_size);
00204     roqvideo_decode_frame(s);
00205 
00206     *data_size = sizeof(AVFrame);
00207     *(AVFrame*)data = *s->current_frame;
00208 
00209     /* shuffle frames */
00210     FFSWAP(AVFrame *, s->current_frame, s->last_frame);
00211 
00212     return buf_size;
00213 }
00214 
00215 static av_cold int roq_decode_end(AVCodecContext *avctx)
00216 {
00217     RoqContext *s = avctx->priv_data;
00218 
00219     /* release the last frame */
00220     if (s->last_frame->data[0])
00221         avctx->release_buffer(avctx, s->last_frame);
00222     if (s->current_frame->data[0])
00223         avctx->release_buffer(avctx, s->current_frame);
00224 
00225     return 0;
00226 }
00227 
00228 AVCodec ff_roq_decoder = {
00229     .name           = "roqvideo",
00230     .type           = AVMEDIA_TYPE_VIDEO,
00231     .id             = AV_CODEC_ID_ROQ,
00232     .priv_data_size = sizeof(RoqContext),
00233     .init           = roq_decode_init,
00234     .close          = roq_decode_end,
00235     .decode         = roq_decode_frame,
00236     .capabilities   = CODEC_CAP_DR1,
00237     .long_name      = NULL_IF_CONFIG_SMALL("id RoQ video"),
00238 };