static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) { AVFrame *frame = data; DxaDecContext * const c = avctx->priv_data; uint8_t *outptr, *srcptr, *tmpptr; unsigned long dsize; int i, j, compr, ret; int stride; int pc = 0; GetByteContext gb; bytestream2_init(&gb, avpkt->data, avpkt->size); /* make the palette available on the way out */ if (bytestream2_peek_le32(&gb) == MKTAG('C','M','A','P')) { bytestream2_skip(&gb, 4); for(i = 0; i < 256; i++){ c->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&gb); } pc = 1; } if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) return ret; memcpy(frame->data[1], c->pal, AVPALETTE_SIZE); frame->palette_has_changed = pc; outptr = frame->data[0]; srcptr = c->decomp_buf; tmpptr = c->prev->data[0]; stride = frame->linesize[0]; if (bytestream2_get_le32(&gb) == MKTAG('N','U','L','L')) compr = -1; else compr = bytestream2_get_byte(&gb); dsize = c->dsize; if (compr != 4 && compr != -1) { bytestream2_skip(&gb, 4); if (uncompress(c->decomp_buf, &dsize, avpkt->data + bytestream2_tell(&gb), bytestream2_get_bytes_left(&gb)) != Z_OK) { av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n"); return AVERROR_UNKNOWN; } memset(c->decomp_buf + dsize, 0, DECOMP_BUF_PADDING); } if (avctx->debug & FF_DEBUG_PICT_INFO) av_log(avctx, AV_LOG_DEBUG, "compr:%2d, dsize:%d\n", compr, (int)dsize); switch(compr){ case -1: frame->key_frame = 0; frame->pict_type = AV_PICTURE_TYPE_P; if (c->prev->data[0]) memcpy(frame->data[0], c->prev->data[0], frame->linesize[0] * avctx->height); else{ // Should happen only when first frame is 'NULL' memset(frame->data[0], 0, frame->linesize[0] * avctx->height); frame->key_frame = 1; frame->pict_type = AV_PICTURE_TYPE_I; } break; case 2: case 4: frame->key_frame = 1; frame->pict_type = AV_PICTURE_TYPE_I; for (j = 0; j < avctx->height; j++) { memcpy(outptr, srcptr, avctx->width); outptr += stride; srcptr += avctx->width; } break; case 3: case 5: if (!tmpptr) { av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n"); if (!(avctx->flags2 & CODEC_FLAG2_SHOW_ALL)) return AVERROR_INVALIDDATA; } frame->key_frame = 0; frame->pict_type = AV_PICTURE_TYPE_P; for (j = 0; j < avctx->height; j++) { if(tmpptr){ for(i = 0; i < avctx->width; i++) outptr[i] = srcptr[i] ^ tmpptr[i]; tmpptr += stride; }else memcpy(outptr, srcptr, avctx->width); outptr += stride; srcptr += avctx->width; } break; case 12: // ScummVM coding case 13: frame->key_frame = 0; frame->pict_type = AV_PICTURE_TYPE_P; if (!c->prev->data[0]) { av_log(avctx, AV_LOG_ERROR, "Missing reference frame\n"); return AVERROR_INVALIDDATA; } decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, c->prev->data[0]); break; default: av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", compr); return AVERROR_INVALIDDATA; } av_frame_unref(c->prev); if ((ret = av_frame_ref(c->prev, frame)) < 0) return ret; *got_frame = 1; /* always report that the buffer was completely consumed */ return avpkt->size; }