static int vmd_read_header(AVFormatContext *s) { VmdDemuxContext *vmd = s->priv_data; AVIOContext *pb = s->pb; AVStream *st = NULL, *vst; unsigned int toc_offset; unsigned char *raw_frame_table; int raw_frame_table_size; int64_t current_offset; int i, j; unsigned int total_frames; int64_t current_audio_pts = 0; unsigned char chunk[BYTES_PER_FRAME_RECORD]; int num, den; int sound_buffers; /* fetch the main header, including the 2 header length bytes */ avio_seek(pb, 0, SEEK_SET); if (avio_read(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE) return AVERROR(EIO); if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3') vmd->is_indeo3 = 1; else vmd->is_indeo3 = 0; /* start up the decoders */ vst = avformat_new_stream(s, NULL); if (!vst) return AVERROR(ENOMEM); avpriv_set_pts_info(vst, 33, 1, 10); vmd->video_stream_index = vst->index; vst->codec->codec_type = AVMEDIA_TYPE_VIDEO; vst->codec->codec_id = vmd->is_indeo3 ? AV_CODEC_ID_INDEO3 : AV_CODEC_ID_VMDVIDEO; vst->codec->codec_tag = 0; /* no fourcc */ vst->codec->width = AV_RL16(&vmd->vmd_header[12]); vst->codec->height = AV_RL16(&vmd->vmd_header[14]); if(vmd->is_indeo3 && vst->codec->width > 320){ vst->codec->width >>= 1; vst->codec->height >>= 1; } vst->codec->extradata_size = VMD_HEADER_SIZE; vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE); memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE); /* if sample rate is 0, assume no audio */ vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]); if (vmd->sample_rate) { st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); vmd->audio_stream_index = st->index; st->codec->codec_type = AVMEDIA_TYPE_AUDIO; st->codec->codec_id = AV_CODEC_ID_VMDAUDIO; st->codec->codec_tag = 0; /* no fourcc */ if (vmd->vmd_header[811] & 0x80) { st->codec->channels = 2; st->codec->channel_layout = AV_CH_LAYOUT_STEREO; } else { st->codec->channels = 1; st->codec->channel_layout = AV_CH_LAYOUT_MONO; } st->codec->sample_rate = vmd->sample_rate; st->codec->block_align = AV_RL16(&vmd->vmd_header[806]); if (st->codec->block_align & 0x8000) { st->codec->bits_per_coded_sample = 16; st->codec->block_align = -(st->codec->block_align - 0x10000); } else { st->codec->bits_per_coded_sample = 8; } st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample * st->codec->channels; /* calculate pts */ num = st->codec->block_align; den = st->codec->sample_rate * st->codec->channels; av_reduce(&den, &num, den, num, (1UL<<31)-1); avpriv_set_pts_info(vst, 33, num, den); avpriv_set_pts_info(st, 33, num, den); } toc_offset = AV_RL32(&vmd->vmd_header[812]); vmd->frame_count = AV_RL16(&vmd->vmd_header[6]); vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]); avio_seek(pb, toc_offset, SEEK_SET); raw_frame_table = NULL; vmd->frame_table = NULL; sound_buffers = AV_RL16(&vmd->vmd_header[808]); raw_frame_table_size = vmd->frame_count * 6; if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){ av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n"); return -1; } raw_frame_table = av_malloc(raw_frame_table_size); vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame)); if (!raw_frame_table || !vmd->frame_table) { av_free(raw_frame_table); av_free(vmd->frame_table); return AVERROR(ENOMEM); } if (avio_read(pb, raw_frame_table, raw_frame_table_size) != raw_frame_table_size) { av_free(raw_frame_table); av_free(vmd->frame_table); return AVERROR(EIO); } total_frames = 0; for (i = 0; i < vmd->frame_count; i++) { current_offset = AV_RL32(&raw_frame_table[6 * i + 2]); /* handle each entry in index block */ for (j = 0; j < vmd->frames_per_block; j++) { int type; uint32_t size; avio_read(pb, chunk, BYTES_PER_FRAME_RECORD); type = chunk[0]; size = AV_RL32(&chunk[2]); if(!size && type != 1) continue; switch(type) { case 1: /* Audio Chunk */ if (!st) break; /* first audio chunk contains several audio buffers */ vmd->frame_table[total_frames].frame_offset = current_offset; vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index; vmd->frame_table[total_frames].frame_size = size; memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD); vmd->frame_table[total_frames].pts = current_audio_pts; total_frames++; if(!current_audio_pts) current_audio_pts += sound_buffers - 1; else current_audio_pts++; break; case 2: /* Video Chunk */ vmd->frame_table[total_frames].frame_offset = current_offset; vmd->frame_table[total_frames].stream_index = vmd->video_stream_index; vmd->frame_table[total_frames].frame_size = size; memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD); vmd->frame_table[total_frames].pts = i; total_frames++; break; } current_offset += size; } } av_free(raw_frame_table); vmd->current_frame = 0; vmd->frame_count = total_frames; return 0; }