static int mp_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; MotionPixelsContext *mp = avctx->priv_data; GetBitContext gb; int i, count1, count2, sz; mp->frame.reference = 1; mp->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE; if (avctx->reget_buffer(avctx, &mp->frame)) { av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); return -1; } /* le32 bitstream msb first */ av_fast_malloc(&mp->bswapbuf, &mp->bswapbuf_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE); if (!mp->bswapbuf) return AVERROR(ENOMEM); mp->dsp.bswap_buf((uint32_t *)mp->bswapbuf, (const uint32_t *)buf, buf_size / 4); if (buf_size & 3) memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3); init_get_bits(&gb, mp->bswapbuf, buf_size * 8); memset(mp->changes_map, 0, avctx->width * avctx->height); for (i = !(avctx->extradata[1] & 2); i < 2; ++i) { count1 = get_bits(&gb, 12); count2 = get_bits(&gb, 12); mp_read_changes_map(mp, &gb, count1, 8, i); mp_read_changes_map(mp, &gb, count2, 4, i); } mp->codes_count = get_bits(&gb, 4); if (mp->codes_count == 0) goto end; if (mp->changes_map[0] == 0) { *(uint16_t *)mp->frame.data[0] = get_bits(&gb, 15); mp->changes_map[0] = 1; } mp_read_codes_table(mp, &gb); sz = get_bits(&gb, 18); if (avctx->extradata[0] != 5) sz += get_bits(&gb, 18); if (sz == 0) goto end; init_vlc(&mp->vlc, mp->max_codes_bits, mp->codes_count, &mp->codes[0].size, sizeof(HuffCode), 1, &mp->codes[0].code, sizeof(HuffCode), 4, 0); mp_decode_frame_helper(mp, &gb); free_vlc(&mp->vlc); end: *data_size = sizeof(AVFrame); *(AVFrame *)data = mp->frame; return buf_size; }