static int tgv_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; TgvContext *s = avctx->priv_data; const uint8_t *buf_end = buf + buf_size; int chunk_type; if (buf_end - buf < EA_PREAMBLE_SIZE) return AVERROR_INVALIDDATA; chunk_type = AV_RL32(&buf[0]); buf += EA_PREAMBLE_SIZE; if (chunk_type==kVGT_TAG) { int pal_count, i; if(buf_end - buf < 12) { av_log(avctx, AV_LOG_WARNING, "truncated header\n"); return -1; } s->width = AV_RL16(&buf[0]); s->height = AV_RL16(&buf[2]); if (s->avctx->width!=s->width || s->avctx->height!=s->height) { avcodec_set_dimensions(s->avctx, s->width, s->height); cond_release_buffer(&s->frame); cond_release_buffer(&s->last_frame); } pal_count = AV_RL16(&buf[6]); buf += 12; for(i=0; i<pal_count && i<AVPALETTE_COUNT && buf_end - buf >= 3; i++) { s->palette[i] = 0xFF << 24 | AV_RB24(buf); buf += 3; } } if (av_image_check_size(s->width, s->height, 0, avctx)) return -1; /* shuffle */ FFSWAP(AVFrame, s->frame, s->last_frame); if (!s->frame.data[0]) { s->frame.reference = 3; s->frame.buffer_hints = FF_BUFFER_HINTS_VALID; s->frame.linesize[0] = s->width; /* allocate additional 12 bytes to accommodate av_memcpy_backptr() OUTBUF_PADDED optimisation */ s->frame.data[0] = av_malloc(s->width*s->height + 12); if (!s->frame.data[0]) return AVERROR(ENOMEM); s->frame.data[1] = av_malloc(AVPALETTE_SIZE); if (!s->frame.data[1]) { av_freep(&s->frame.data[0]); return AVERROR(ENOMEM); } } memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE); if(chunk_type==kVGT_TAG) { s->frame.key_frame = 1; s->frame.pict_type = AV_PICTURE_TYPE_I; if (unpack(buf, buf_end, s->frame.data[0], s->avctx->width, s->avctx->height)<0) { av_log(avctx, AV_LOG_WARNING, "truncated intra frame\n"); return -1; } }else{ if (!s->last_frame.data[0]) { av_log(avctx, AV_LOG_WARNING, "inter frame without corresponding intra frame\n"); return buf_size; } s->frame.key_frame = 0; s->frame.pict_type = AV_PICTURE_TYPE_P; if (tgv_decode_inter(s, buf, buf_end)<0) { av_log(avctx, AV_LOG_WARNING, "truncated inter frame\n"); return -1; } } *data_size = sizeof(AVFrame); *(AVFrame*)data = s->frame; return buf_size; }