FFmpeg: libavformat/ipmovie.c Source File

00001 /*
00002  * Interplay MVE File Demuxer
00003  * Copyright (c) 2003 The ffmpeg Project
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00035 #include "libavutil/intreadwrite.h"
00036 #include "avformat.h"
00037 
00038 /* debugging support: #define DEBUG_IPMOVIE as non-zero to see extremely
00039  * verbose information about the demux process */
00040 #define DEBUG_IPMOVIE 0
00041 
00042 #if DEBUG_IPMOVIE
00043 #undef printf
00044 #define debug_ipmovie printf
00045 #else
00046 static inline void debug_ipmovie(const char *format, ...) { }
00047 #endif
00048 
00049 #define IPMOVIE_SIGNATURE "Interplay MVE File\x1A\0"
00050 #define IPMOVIE_SIGNATURE_SIZE 20
00051 #define CHUNK_PREAMBLE_SIZE 4
00052 #define OPCODE_PREAMBLE_SIZE 4
00053 
00054 #define CHUNK_INIT_AUDIO   0x0000
00055 #define CHUNK_AUDIO_ONLY   0x0001
00056 #define CHUNK_INIT_VIDEO   0x0002
00057 #define CHUNK_VIDEO        0x0003
00058 #define CHUNK_SHUTDOWN     0x0004
00059 #define CHUNK_END          0x0005
00060 /* these last types are used internally */
00061 #define CHUNK_DONE         0xFFFC
00062 #define CHUNK_NOMEM        0xFFFD
00063 #define CHUNK_EOF          0xFFFE
00064 #define CHUNK_BAD          0xFFFF
00065 
00066 #define OPCODE_END_OF_STREAM           0x00
00067 #define OPCODE_END_OF_CHUNK            0x01
00068 #define OPCODE_CREATE_TIMER            0x02
00069 #define OPCODE_INIT_AUDIO_BUFFERS      0x03
00070 #define OPCODE_START_STOP_AUDIO        0x04
00071 #define OPCODE_INIT_VIDEO_BUFFERS      0x05
00072 #define OPCODE_UNKNOWN_06              0x06
00073 #define OPCODE_SEND_BUFFER             0x07
00074 #define OPCODE_AUDIO_FRAME             0x08
00075 #define OPCODE_SILENCE_FRAME           0x09
00076 #define OPCODE_INIT_VIDEO_MODE         0x0A
00077 #define OPCODE_CREATE_GRADIENT         0x0B
00078 #define OPCODE_SET_PALETTE             0x0C
00079 #define OPCODE_SET_PALETTE_COMPRESSED  0x0D
00080 #define OPCODE_UNKNOWN_0E              0x0E
00081 #define OPCODE_SET_DECODING_MAP        0x0F
00082 #define OPCODE_UNKNOWN_10              0x10
00083 #define OPCODE_VIDEO_DATA              0x11
00084 #define OPCODE_UNKNOWN_12              0x12
00085 #define OPCODE_UNKNOWN_13              0x13
00086 #define OPCODE_UNKNOWN_14              0x14
00087 #define OPCODE_UNKNOWN_15              0x15
00088 
00089 #define PALETTE_COUNT 256
00090 
00091 typedef struct IPMVEContext {
00092 
00093     unsigned char *buf;
00094     int buf_size;
00095 
00096     uint64_t frame_pts_inc;
00097 
00098     unsigned int video_width;
00099     unsigned int video_height;
00100     int64_t video_pts;
00101 
00102     unsigned int audio_bits;
00103     unsigned int audio_channels;
00104     unsigned int audio_sample_rate;
00105     enum CodecID audio_type;
00106     unsigned int audio_frame_count;
00107 
00108     int video_stream_index;
00109     int audio_stream_index;
00110 
00111     int64_t audio_chunk_offset;
00112     int audio_chunk_size;
00113     int64_t video_chunk_offset;
00114     int video_chunk_size;
00115     int64_t decode_map_chunk_offset;
00116     int decode_map_chunk_size;
00117 
00118     int64_t next_chunk_offset;
00119 
00120     AVPaletteControl palette_control;
00121 
00122 } IPMVEContext;
00123 
00124 static int load_ipmovie_packet(IPMVEContext *s, ByteIOContext *pb,
00125     AVPacket *pkt) {
00126 
00127     int chunk_type;
00128 
00129     if (s->audio_chunk_offset) {
00130 
00131         /* adjust for PCM audio by skipping chunk header */
00132         if (s->audio_type != CODEC_ID_INTERPLAY_DPCM) {
00133             s->audio_chunk_offset += 6;
00134             s->audio_chunk_size -= 6;
00135         }
00136 
00137         url_fseek(pb, s->audio_chunk_offset, SEEK_SET);
00138         s->audio_chunk_offset = 0;
00139 
00140         if (s->audio_chunk_size != av_get_packet(pb, pkt, s->audio_chunk_size))
00141             return CHUNK_EOF;
00142 
00143         pkt->stream_index = s->audio_stream_index;
00144         pkt->pts = s->audio_frame_count;
00145 
00146         /* audio frame maintenance */
00147         if (s->audio_type != CODEC_ID_INTERPLAY_DPCM)
00148             s->audio_frame_count +=
00149             (s->audio_chunk_size / s->audio_channels / (s->audio_bits / 8));
00150         else
00151             s->audio_frame_count +=
00152                 (s->audio_chunk_size - 6) / s->audio_channels;
00153 
00154         debug_ipmovie("sending audio frame with pts %"PRId64" (%d audio frames)\n",
00155             pkt->pts, s->audio_frame_count);
00156 
00157         chunk_type = CHUNK_VIDEO;
00158 
00159     } else if (s->decode_map_chunk_offset) {
00160 
00161         /* send both the decode map and the video data together */
00162 
00163         if (av_new_packet(pkt, s->decode_map_chunk_size + s->video_chunk_size))
00164             return CHUNK_NOMEM;
00165 
00166         pkt->pos= s->decode_map_chunk_offset;
00167         url_fseek(pb, s->decode_map_chunk_offset, SEEK_SET);
00168         s->decode_map_chunk_offset = 0;
00169 
00170         if (get_buffer(pb, pkt->data, s->decode_map_chunk_size) !=
00171             s->decode_map_chunk_size) {
00172             av_free_packet(pkt);
00173             return CHUNK_EOF;
00174         }
00175 
00176         url_fseek(pb, s->video_chunk_offset, SEEK_SET);
00177         s->video_chunk_offset = 0;
00178 
00179         if (get_buffer(pb, pkt->data + s->decode_map_chunk_size,
00180             s->video_chunk_size) != s->video_chunk_size) {
00181             av_free_packet(pkt);
00182             return CHUNK_EOF;
00183         }
00184 
00185         pkt->stream_index = s->video_stream_index;
00186         pkt->pts = s->video_pts;
00187 
00188         debug_ipmovie("sending video frame with pts %"PRId64"\n",
00189             pkt->pts);
00190 
00191         s->video_pts += s->frame_pts_inc;
00192 
00193         chunk_type = CHUNK_VIDEO;
00194 
00195     } else {
00196 
00197         url_fseek(pb, s->next_chunk_offset, SEEK_SET);
00198         chunk_type = CHUNK_DONE;
00199 
00200     }
00201 
00202     return chunk_type;
00203 }
00204 
00205 /* This function loads and processes a single chunk in an IP movie file.
00206  * It returns the type of chunk that was processed. */
00207 static int process_ipmovie_chunk(IPMVEContext *s, ByteIOContext *pb,
00208     AVPacket *pkt)
00209 {
00210     unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
00211     int chunk_type;
00212     int chunk_size;
00213     unsigned char opcode_preamble[OPCODE_PREAMBLE_SIZE];
00214     unsigned char opcode_type;
00215     unsigned char opcode_version;
00216     int opcode_size;
00217     unsigned char scratch[1024];
00218     int i, j;
00219     int first_color, last_color;
00220     int audio_flags;
00221     unsigned char r, g, b;
00222 
00223     /* see if there are any pending packets */
00224     chunk_type = load_ipmovie_packet(s, pb, pkt);
00225     if (chunk_type != CHUNK_DONE)
00226         return chunk_type;
00227 
00228     /* read the next chunk, wherever the file happens to be pointing */
00229     if (url_feof(pb))
00230         return CHUNK_EOF;
00231     if (get_buffer(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
00232         CHUNK_PREAMBLE_SIZE)
00233         return CHUNK_BAD;
00234     chunk_size = AV_RL16(&chunk_preamble[0]);
00235     chunk_type = AV_RL16(&chunk_preamble[2]);
00236 
00237     debug_ipmovie("chunk type 0x%04X, 0x%04X bytes: ", chunk_type, chunk_size);
00238 
00239     switch (chunk_type) {
00240 
00241     case CHUNK_INIT_AUDIO:
00242         debug_ipmovie("initialize audio\n");
00243         break;
00244 
00245     case CHUNK_AUDIO_ONLY:
00246         debug_ipmovie("audio only\n");
00247         break;
00248 
00249     case CHUNK_INIT_VIDEO:
00250         debug_ipmovie("initialize video\n");
00251         break;
00252 
00253     case CHUNK_VIDEO:
00254         debug_ipmovie("video (and audio)\n");
00255         break;
00256 
00257     case CHUNK_SHUTDOWN:
00258         debug_ipmovie("shutdown\n");
00259         break;
00260 
00261     case CHUNK_END:
00262         debug_ipmovie("end\n");
00263         break;
00264 
00265     default:
00266         debug_ipmovie("invalid chunk\n");
00267         chunk_type = CHUNK_BAD;
00268         break;
00269 
00270     }
00271 
00272     while ((chunk_size > 0) && (chunk_type != CHUNK_BAD)) {
00273 
00274         /* read the next chunk, wherever the file happens to be pointing */
00275        if (url_feof(pb)) {
00276             chunk_type = CHUNK_EOF;
00277             break;
00278         }
00279         if (get_buffer(pb, opcode_preamble, CHUNK_PREAMBLE_SIZE) !=
00280             CHUNK_PREAMBLE_SIZE) {
00281             chunk_type = CHUNK_BAD;
00282             break;
00283         }
00284 
00285         opcode_size = AV_RL16(&opcode_preamble[0]);
00286         opcode_type = opcode_preamble[2];
00287         opcode_version = opcode_preamble[3];
00288 
00289         chunk_size -= OPCODE_PREAMBLE_SIZE;
00290         chunk_size -= opcode_size;
00291         if (chunk_size < 0) {
00292             debug_ipmovie("chunk_size countdown just went negative\n");
00293             chunk_type = CHUNK_BAD;
00294             break;
00295         }
00296 
00297         debug_ipmovie("  opcode type %02X, version %d, 0x%04X bytes: ",
00298             opcode_type, opcode_version, opcode_size);
00299         switch (opcode_type) {
00300 
00301         case OPCODE_END_OF_STREAM:
00302             debug_ipmovie("end of stream\n");
00303             url_fseek(pb, opcode_size, SEEK_CUR);
00304             break;
00305 
00306         case OPCODE_END_OF_CHUNK:
00307             debug_ipmovie("end of chunk\n");
00308             url_fseek(pb, opcode_size, SEEK_CUR);
00309             break;
00310 
00311         case OPCODE_CREATE_TIMER:
00312             debug_ipmovie("create timer\n");
00313             if ((opcode_version > 0) || (opcode_size > 6)) {
00314                 debug_ipmovie("bad create_timer opcode\n");
00315                 chunk_type = CHUNK_BAD;
00316                 break;
00317             }
00318             if (get_buffer(pb, scratch, opcode_size) !=
00319                 opcode_size) {
00320                 chunk_type = CHUNK_BAD;
00321                 break;
00322             }
00323             s->frame_pts_inc = ((uint64_t)AV_RL32(&scratch[0])) * AV_RL16(&scratch[4]);
00324             debug_ipmovie("  %.2f frames/second (timer div = %d, subdiv = %d)\n",
00325                 1000000.0/s->frame_pts_inc, AV_RL32(&scratch[0]), AV_RL16(&scratch[4]));
00326             break;
00327 
00328         case OPCODE_INIT_AUDIO_BUFFERS:
00329             debug_ipmovie("initialize audio buffers\n");
00330             if ((opcode_version > 1) || (opcode_size > 10)) {
00331                 debug_ipmovie("bad init_audio_buffers opcode\n");
00332                 chunk_type = CHUNK_BAD;
00333                 break;
00334             }
00335             if (get_buffer(pb, scratch, opcode_size) !=
00336                 opcode_size) {
00337                 chunk_type = CHUNK_BAD;
00338                 break;
00339             }
00340             s->audio_sample_rate = AV_RL16(&scratch[4]);
00341             audio_flags = AV_RL16(&scratch[2]);
00342             /* bit 0 of the flags: 0 = mono, 1 = stereo */
00343             s->audio_channels = (audio_flags & 1) + 1;
00344             /* bit 1 of the flags: 0 = 8 bit, 1 = 16 bit */
00345             s->audio_bits = (((audio_flags >> 1) & 1) + 1) * 8;
00346             /* bit 2 indicates compressed audio in version 1 opcode */
00347             if ((opcode_version == 1) && (audio_flags & 0x4))
00348                 s->audio_type = CODEC_ID_INTERPLAY_DPCM;
00349             else if (s->audio_bits == 16)
00350                 s->audio_type = CODEC_ID_PCM_S16LE;
00351             else
00352                 s->audio_type = CODEC_ID_PCM_U8;
00353             debug_ipmovie("audio: %d bits, %d Hz, %s, %s format\n",
00354                 s->audio_bits,
00355                 s->audio_sample_rate,
00356                 (s->audio_channels == 2) ? "stereo" : "mono",
00357                 (s->audio_type == CODEC_ID_INTERPLAY_DPCM) ?
00358                 "Interplay audio" : "PCM");
00359             break;
00360 
00361         case OPCODE_START_STOP_AUDIO:
00362             debug_ipmovie("start/stop audio\n");
00363             url_fseek(pb, opcode_size, SEEK_CUR);
00364             break;
00365 
00366         case OPCODE_INIT_VIDEO_BUFFERS:
00367             debug_ipmovie("initialize video buffers\n");
00368             if ((opcode_version > 2) || (opcode_size > 8)) {
00369                 debug_ipmovie("bad init_video_buffers opcode\n");
00370                 chunk_type = CHUNK_BAD;
00371                 break;
00372             }
00373             if (get_buffer(pb, scratch, opcode_size) !=
00374                 opcode_size) {
00375                 chunk_type = CHUNK_BAD;
00376                 break;
00377             }
00378             s->video_width = AV_RL16(&scratch[0]) * 8;
00379             s->video_height = AV_RL16(&scratch[2]) * 8;
00380             debug_ipmovie("video resolution: %d x %d\n",
00381                 s->video_width, s->video_height);
00382             break;
00383 
00384         case OPCODE_UNKNOWN_06:
00385         case OPCODE_UNKNOWN_0E:
00386         case OPCODE_UNKNOWN_10:
00387         case OPCODE_UNKNOWN_12:
00388         case OPCODE_UNKNOWN_13:
00389         case OPCODE_UNKNOWN_14:
00390         case OPCODE_UNKNOWN_15:
00391             debug_ipmovie("unknown (but documented) opcode %02X\n", opcode_type);
00392             url_fseek(pb, opcode_size, SEEK_CUR);
00393             break;
00394 
00395         case OPCODE_SEND_BUFFER:
00396             debug_ipmovie("send buffer\n");
00397             url_fseek(pb, opcode_size, SEEK_CUR);
00398             break;
00399 
00400         case OPCODE_AUDIO_FRAME:
00401             debug_ipmovie("audio frame\n");
00402 
00403             /* log position and move on for now */
00404             s->audio_chunk_offset = url_ftell(pb);
00405             s->audio_chunk_size = opcode_size;
00406             url_fseek(pb, opcode_size, SEEK_CUR);
00407             break;
00408 
00409         case OPCODE_SILENCE_FRAME:
00410             debug_ipmovie("silence frame\n");
00411             url_fseek(pb, opcode_size, SEEK_CUR);
00412             break;
00413 
00414         case OPCODE_INIT_VIDEO_MODE:
00415             debug_ipmovie("initialize video mode\n");
00416             url_fseek(pb, opcode_size, SEEK_CUR);
00417             break;
00418 
00419         case OPCODE_CREATE_GRADIENT:
00420             debug_ipmovie("create gradient\n");
00421             url_fseek(pb, opcode_size, SEEK_CUR);
00422             break;
00423 
00424         case OPCODE_SET_PALETTE:
00425             debug_ipmovie("set palette\n");
00426             /* check for the logical maximum palette size
00427              * (3 * 256 + 4 bytes) */
00428             if (opcode_size > 0x304) {
00429                 debug_ipmovie("demux_ipmovie: set_palette opcode too large\n");
00430                 chunk_type = CHUNK_BAD;
00431                 break;
00432             }
00433             if (get_buffer(pb, scratch, opcode_size) != opcode_size) {
00434                 chunk_type = CHUNK_BAD;
00435                 break;
00436             }
00437 
00438             /* load the palette into internal data structure */
00439             first_color = AV_RL16(&scratch[0]);
00440             last_color = first_color + AV_RL16(&scratch[2]) - 1;
00441             /* sanity check (since they are 16 bit values) */
00442             if ((first_color > 0xFF) || (last_color > 0xFF)) {
00443                 debug_ipmovie("demux_ipmovie: set_palette indexes out of range (%d -> %d)\n",
00444                     first_color, last_color);
00445                 chunk_type = CHUNK_BAD;
00446                 break;
00447             }
00448             j = 4;  /* offset of first palette data */
00449             for (i = first_color; i <= last_color; i++) {
00450                 /* the palette is stored as a 6-bit VGA palette, thus each
00451                  * component is shifted up to a 8-bit range */
00452                 r = scratch[j++] * 4;
00453                 g = scratch[j++] * 4;
00454                 b = scratch[j++] * 4;
00455                 s->palette_control.palette[i] = (r << 16) | (g << 8) | (b);
00456             }
00457             /* indicate a palette change */
00458             s->palette_control.palette_changed = 1;
00459             break;
00460 
00461         case OPCODE_SET_PALETTE_COMPRESSED:
00462             debug_ipmovie("set palette compressed\n");
00463             url_fseek(pb, opcode_size, SEEK_CUR);
00464             break;
00465 
00466         case OPCODE_SET_DECODING_MAP:
00467             debug_ipmovie("set decoding map\n");
00468 
00469             /* log position and move on for now */
00470             s->decode_map_chunk_offset = url_ftell(pb);
00471             s->decode_map_chunk_size = opcode_size;
00472             url_fseek(pb, opcode_size, SEEK_CUR);
00473             break;
00474 
00475         case OPCODE_VIDEO_DATA:
00476             debug_ipmovie("set video data\n");
00477 
00478             /* log position and move on for now */
00479             s->video_chunk_offset = url_ftell(pb);
00480             s->video_chunk_size = opcode_size;
00481             url_fseek(pb, opcode_size, SEEK_CUR);
00482             break;
00483 
00484         default:
00485             debug_ipmovie("*** unknown opcode type\n");
00486             chunk_type = CHUNK_BAD;
00487             break;
00488 
00489         }
00490     }
00491 
00492     /* make a note of where the stream is sitting */
00493     s->next_chunk_offset = url_ftell(pb);
00494 
00495     /* dispatch the first of any pending packets */
00496     if ((chunk_type == CHUNK_VIDEO) || (chunk_type == CHUNK_AUDIO_ONLY))
00497         chunk_type = load_ipmovie_packet(s, pb, pkt);
00498 
00499     return chunk_type;
00500 }
00501 
00502 static int ipmovie_probe(AVProbeData *p)
00503 {
00504     if (strncmp(p->buf, IPMOVIE_SIGNATURE, IPMOVIE_SIGNATURE_SIZE) != 0)
00505         return 0;
00506 
00507     return AVPROBE_SCORE_MAX;
00508 }
00509 
00510 static int ipmovie_read_header(AVFormatContext *s,
00511                                AVFormatParameters *ap)
00512 {
00513     IPMVEContext *ipmovie = s->priv_data;
00514     ByteIOContext *pb = s->pb;
00515     AVPacket pkt;
00516     AVStream *st;
00517     unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
00518     int chunk_type;
00519 
00520     /* initialize private context members */
00521     ipmovie->video_pts = ipmovie->audio_frame_count = 0;
00522     ipmovie->audio_chunk_offset = ipmovie->video_chunk_offset =
00523     ipmovie->decode_map_chunk_offset = 0;
00524 
00525     /* on the first read, this will position the stream at the first chunk */
00526     ipmovie->next_chunk_offset = IPMOVIE_SIGNATURE_SIZE + 6;
00527 
00528     /* process the first chunk which should be CHUNK_INIT_VIDEO */
00529     if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_VIDEO)
00530         return AVERROR_INVALIDDATA;
00531 
00532     /* peek ahead to the next chunk-- if it is an init audio chunk, process
00533      * it; if it is the first video chunk, this is a silent file */
00534     if (get_buffer(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
00535         CHUNK_PREAMBLE_SIZE)
00536         return AVERROR(EIO);
00537     chunk_type = AV_RL16(&chunk_preamble[2]);
00538     url_fseek(pb, -CHUNK_PREAMBLE_SIZE, SEEK_CUR);
00539 
00540     if (chunk_type == CHUNK_VIDEO)
00541         ipmovie->audio_type = CODEC_ID_NONE;  /* no audio */
00542     else if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_AUDIO)
00543         return AVERROR_INVALIDDATA;
00544 
00545     /* initialize the stream decoders */
00546     st = av_new_stream(s, 0);
00547     if (!st)
00548         return AVERROR(ENOMEM);
00549     av_set_pts_info(st, 63, 1, 1000000);
00550     ipmovie->video_stream_index = st->index;
00551     st->codec->codec_type = CODEC_TYPE_VIDEO;
00552     st->codec->codec_id = CODEC_ID_INTERPLAY_VIDEO;
00553     st->codec->codec_tag = 0;  /* no fourcc */
00554     st->codec->width = ipmovie->video_width;
00555     st->codec->height = ipmovie->video_height;
00556 
00557     /* palette considerations */
00558     st->codec->palctrl = &ipmovie->palette_control;
00559 
00560     if (ipmovie->audio_type) {
00561         st = av_new_stream(s, 0);
00562         if (!st)
00563             return AVERROR(ENOMEM);
00564         av_set_pts_info(st, 32, 1, ipmovie->audio_sample_rate);
00565         ipmovie->audio_stream_index = st->index;
00566         st->codec->codec_type = CODEC_TYPE_AUDIO;
00567         st->codec->codec_id = ipmovie->audio_type;
00568         st->codec->codec_tag = 0;  /* no tag */
00569         st->codec->channels = ipmovie->audio_channels;
00570         st->codec->sample_rate = ipmovie->audio_sample_rate;
00571         st->codec->bits_per_coded_sample = ipmovie->audio_bits;
00572         st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
00573             st->codec->bits_per_coded_sample;
00574         if (st->codec->codec_id == CODEC_ID_INTERPLAY_DPCM)
00575             st->codec->bit_rate /= 2;
00576         st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00577     }
00578 
00579     return 0;
00580 }
00581 
00582 static int ipmovie_read_packet(AVFormatContext *s,
00583                                AVPacket *pkt)
00584 {
00585     IPMVEContext *ipmovie = s->priv_data;
00586     ByteIOContext *pb = s->pb;
00587     int ret;
00588 
00589     ret = process_ipmovie_chunk(ipmovie, pb, pkt);
00590     if (ret == CHUNK_BAD)
00591         ret = AVERROR_INVALIDDATA;
00592     else if (ret == CHUNK_EOF)
00593         ret = AVERROR(EIO);
00594     else if (ret == CHUNK_NOMEM)
00595         ret = AVERROR(ENOMEM);
00596     else if (ret == CHUNK_VIDEO)
00597         ret = 0;
00598     else
00599         ret = -1;
00600 
00601     return ret;
00602 }
00603 
00604 AVInputFormat ipmovie_demuxer = {
00605     "ipmovie",
00606     NULL_IF_CONFIG_SMALL("Interplay MVE format"),
00607     sizeof(IPMVEContext),
00608     ipmovie_probe,
00609     ipmovie_read_header,
00610     ipmovie_read_packet,
00611 };