yading@10: /*
yading@10:  * Feeble Files/ScummVM DXA decoder
yading@10:  * Copyright (c) 2007 Konstantin Shishkov
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * DXA Video decoder
yading@10:  */
yading@10: 
yading@10: #include <stdio.h>
yading@10: #include <stdlib.h>
yading@10: 
yading@10: #include "libavutil/common.h"
yading@10: #include "libavutil/intreadwrite.h"
yading@10: #include "bytestream.h"
yading@10: #include "avcodec.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: #include <zlib.h>
yading@10: 
yading@10: /*
yading@10:  * Decoder context
yading@10:  */
yading@10: typedef struct DxaDecContext {
yading@10:     AVFrame prev;
yading@10: 
yading@10:     int dsize;
yading@10:     uint8_t *decomp_buf;
yading@10:     uint32_t pal[256];
yading@10: } DxaDecContext;
yading@10: 
yading@10: static const int shift1[6] = { 0, 8, 8, 8, 4, 4 };
yading@10: static const int shift2[6] = { 0, 0, 8, 4, 0, 4 };
yading@10: 
yading@10: static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
yading@10:                      int stride, uint8_t *src, uint8_t *ref)
yading@10: {
yading@10:     uint8_t *code, *data, *mv, *msk, *tmp, *tmp2;
yading@10:     int i, j, k;
yading@10:     int type, x, y, d, d2;
yading@10:     uint32_t mask;
yading@10: 
yading@10:     code = src  + 12;
yading@10:     data = code + ((avctx->width * avctx->height) >> 4);
yading@10:     mv   = data + AV_RB32(src + 0);
yading@10:     msk  = mv   + AV_RB32(src + 4);
yading@10: 
yading@10:     for(j = 0; j < avctx->height; j += 4){
yading@10:         for(i = 0; i < avctx->width; i += 4){
yading@10:             tmp  = dst + i;
yading@10:             tmp2 = ref + i;
yading@10:             type = *code++;
yading@10:             switch(type){
yading@10:             case 4: // motion compensation
yading@10:                 x = (*mv) >> 4;    if(x & 8) x = 8 - x;
yading@10:                 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
yading@10:                 tmp2 += x + y*stride;
yading@10:             case 0: // skip
yading@10:             case 5: // skip in method 12
yading@10:                 for(y = 0; y < 4; y++){
yading@10:                     memcpy(tmp, tmp2, 4);
yading@10:                     tmp  += stride;
yading@10:                     tmp2 += stride;
yading@10:                 }
yading@10:                 break;
yading@10:             case 1:  // masked change
yading@10:             case 10: // masked change with only half of pixels changed
yading@10:             case 11: // cases 10-15 are for method 12 only
yading@10:             case 12:
yading@10:             case 13:
yading@10:             case 14:
yading@10:             case 15:
yading@10:                 if(type == 1){
yading@10:                     mask = AV_RB16(msk);
yading@10:                     msk += 2;
yading@10:                 }else{
yading@10:                     type -= 10;
yading@10:                     mask = ((msk[0] & 0xF0) << shift1[type]) | ((msk[0] & 0xF) << shift2[type]);
yading@10:                     msk++;
yading@10:                 }
yading@10:                 for(y = 0; y < 4; y++){
yading@10:                     for(x = 0; x < 4; x++){
yading@10:                         tmp[x] = (mask & 0x8000) ? *data++ : tmp2[x];
yading@10:                         mask <<= 1;
yading@10:                     }
yading@10:                     tmp  += stride;
yading@10:                     tmp2 += stride;
yading@10:                 }
yading@10:                 break;
yading@10:             case 2: // fill block
yading@10:                 for(y = 0; y < 4; y++){
yading@10:                     memset(tmp, data[0], 4);
yading@10:                     tmp += stride;
yading@10:                 }
yading@10:                 data++;
yading@10:                 break;
yading@10:             case 3: // raw block
yading@10:                 for(y = 0; y < 4; y++){
yading@10:                     memcpy(tmp, data, 4);
yading@10:                     data += 4;
yading@10:                     tmp  += stride;
yading@10:                 }
yading@10:                 break;
yading@10:             case 8: // subblocks - method 13 only
yading@10:                 mask = *msk++;
yading@10:                 for(k = 0; k < 4; k++){
yading@10:                     d  = ((k & 1) << 1) + ((k & 2) * stride);
yading@10:                     d2 = ((k & 1) << 1) + ((k & 2) * stride);
yading@10:                     tmp2 = ref + i + d2;
yading@10:                     switch(mask & 0xC0){
yading@10:                     case 0x80: // motion compensation
yading@10:                         x = (*mv) >> 4;    if(x & 8) x = 8 - x;
yading@10:                         y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
yading@10:                         tmp2 += x + y*stride;
yading@10:                     case 0x00: // skip
yading@10:                         tmp[d + 0         ] = tmp2[0];
yading@10:                         tmp[d + 1         ] = tmp2[1];
yading@10:                         tmp[d + 0 + stride] = tmp2[0 + stride];
yading@10:                         tmp[d + 1 + stride] = tmp2[1 + stride];
yading@10:                         break;
yading@10:                     case 0x40: // fill
yading@10:                         tmp[d + 0         ] = data[0];
yading@10:                         tmp[d + 1         ] = data[0];
yading@10:                         tmp[d + 0 + stride] = data[0];
yading@10:                         tmp[d + 1 + stride] = data[0];
yading@10:                         data++;
yading@10:                         break;
yading@10:                     case 0xC0: // raw
yading@10:                         tmp[d + 0         ] = *data++;
yading@10:                         tmp[d + 1         ] = *data++;
yading@10:                         tmp[d + 0 + stride] = *data++;
yading@10:                         tmp[d + 1 + stride] = *data++;
yading@10:                         break;
yading@10:                     }
yading@10:                     mask <<= 2;
yading@10:                 }
yading@10:                 break;
yading@10:             case 32: // vector quantization - 2 colors
yading@10:                 mask = AV_RB16(msk);
yading@10:                 msk += 2;
yading@10:                 for(y = 0; y < 4; y++){
yading@10:                     for(x = 0; x < 4; x++){
yading@10:                         tmp[x] = data[mask & 1];
yading@10:                         mask >>= 1;
yading@10:                     }
yading@10:                     tmp  += stride;
yading@10:                     tmp2 += stride;
yading@10:                 }
yading@10:                 data += 2;
yading@10:                 break;
yading@10:             case 33: // vector quantization - 3 or 4 colors
yading@10:             case 34:
yading@10:                 mask = AV_RB32(msk);
yading@10:                 msk += 4;
yading@10:                 for(y = 0; y < 4; y++){
yading@10:                     for(x = 0; x < 4; x++){
yading@10:                         tmp[x] = data[mask & 3];
yading@10:                         mask >>= 2;
yading@10:                     }
yading@10:                     tmp  += stride;
yading@10:                     tmp2 += stride;
yading@10:                 }
yading@10:                 data += type - 30;
yading@10:                 break;
yading@10:             default:
yading@10:                 av_log(avctx, AV_LOG_ERROR, "Unknown opcode %d\n", type);
yading@10:                 return AVERROR_INVALIDDATA;
yading@10:             }
yading@10:         }
yading@10:         dst += stride * 4;
yading@10:         ref += stride * 4;
yading@10:     }
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
yading@10: {
yading@10:     AVFrame *frame = data;
yading@10:     DxaDecContext * const c = avctx->priv_data;
yading@10:     uint8_t *outptr, *srcptr, *tmpptr;
yading@10:     unsigned long dsize;
yading@10:     int i, j, compr, ret;
yading@10:     int stride;
yading@10:     int pc = 0;
yading@10:     GetByteContext gb;
yading@10: 
yading@10:     bytestream2_init(&gb, avpkt->data, avpkt->size);
yading@10: 
yading@10:     /* make the palette available on the way out */
yading@10:     if (bytestream2_peek_le32(&gb) == MKTAG('C','M','A','P')) {
yading@10:         bytestream2_skip(&gb, 4);
yading@10:         for(i = 0; i < 256; i++){
yading@10:             c->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&gb);
yading@10:         }
yading@10:         pc = 1;
yading@10:     }
yading@10: 
yading@10:     if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
yading@10:         return ret;
yading@10:     memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
yading@10:     frame->palette_has_changed = pc;
yading@10: 
yading@10:     outptr = frame->data[0];
yading@10:     srcptr = c->decomp_buf;
yading@10:     tmpptr = c->prev.data[0];
yading@10:     stride = frame->linesize[0];
yading@10: 
yading@10:     if (bytestream2_get_le32(&gb) == MKTAG('N','U','L','L'))
yading@10:         compr = -1;
yading@10:     else
yading@10:         compr = bytestream2_get_byte(&gb);
yading@10: 
yading@10:     dsize = c->dsize;
yading@10:     if (compr != 4 && compr != -1) {
yading@10:         bytestream2_skip(&gb, 4);
yading@10:         if (uncompress(c->decomp_buf, &dsize, avpkt->data + bytestream2_tell(&gb),
yading@10:                        bytestream2_get_bytes_left(&gb)) != Z_OK) {
yading@10:             av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n");
yading@10:             return AVERROR_UNKNOWN;
yading@10:         }
yading@10:     }
yading@10:     switch(compr){
yading@10:     case -1:
yading@10:         frame->key_frame = 0;
yading@10:         frame->pict_type = AV_PICTURE_TYPE_P;
yading@10:         if(c->prev.data[0])
yading@10:             memcpy(frame->data[0], c->prev.data[0], frame->linesize[0] * avctx->height);
yading@10:         else{ // Should happen only when first frame is 'NULL'
yading@10:             memset(frame->data[0], 0, frame->linesize[0] * avctx->height);
yading@10:             frame->key_frame = 1;
yading@10:             frame->pict_type = AV_PICTURE_TYPE_I;
yading@10:         }
yading@10:         break;
yading@10:     case 2:
yading@10:     case 3:
yading@10:     case 4:
yading@10:     case 5:
yading@10:         frame->key_frame = !(compr & 1);
yading@10:         frame->pict_type = (compr & 1) ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
yading@10:         for(j = 0; j < avctx->height; j++){
yading@10:             if((compr & 1) && tmpptr){
yading@10:                 for(i = 0; i < avctx->width; i++)
yading@10:                     outptr[i] = srcptr[i] ^ tmpptr[i];
yading@10:                 tmpptr += stride;
yading@10:             }else
yading@10:                 memcpy(outptr, srcptr, avctx->width);
yading@10:             outptr += stride;
yading@10:             srcptr += avctx->width;
yading@10:         }
yading@10:         break;
yading@10:     case 12: // ScummVM coding
yading@10:     case 13:
yading@10:         frame->key_frame = 0;
yading@10:         frame->pict_type = AV_PICTURE_TYPE_P;
yading@10:         if (!c->prev.data[0]) {
yading@10:             av_log(avctx, AV_LOG_ERROR, "Missing reference frame\n");
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10:         decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, c->prev.data[0]);
yading@10:         break;
yading@10:     default:
yading@10:         av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", compr);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     av_frame_unref(&c->prev);
yading@10:     if ((ret = av_frame_ref(&c->prev, frame)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     *got_frame = 1;
yading@10: 
yading@10:     /* always report that the buffer was completely consumed */
yading@10:     return avpkt->size;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     DxaDecContext * const c = avctx->priv_data;
yading@10: 
yading@10:     avctx->pix_fmt = AV_PIX_FMT_PAL8;
yading@10: 
yading@10:     avcodec_get_frame_defaults(&c->prev);
yading@10: 
yading@10:     c->dsize = avctx->width * avctx->height * 2;
yading@10:     c->decomp_buf = av_malloc(c->dsize);
yading@10:     if (!c->decomp_buf) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
yading@10:         return AVERROR(ENOMEM);
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_end(AVCodecContext *avctx)
yading@10: {
yading@10:     DxaDecContext * const c = avctx->priv_data;
yading@10: 
yading@10:     av_freep(&c->decomp_buf);
yading@10:     av_frame_unref(&c->prev);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_dxa_decoder = {
yading@10:     .name           = "dxa",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_DXA,
yading@10:     .priv_data_size = sizeof(DxaDecContext),
yading@10:     .init           = decode_init,
yading@10:     .close          = decode_end,
yading@10:     .decode         = decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("Feeble Files/ScummVM DXA"),
yading@10: };