ffmpeg/libavcodec/dxtory.c

111 lines
3.1 KiB
C

/*
* Dxtory decoder
*
* Copyright (c) 2011 Konstantin Shishkov
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
static av_cold int decode_init(AVCodecContext *avctx)
{
avctx->pix_fmt = PIX_FMT_YUV420P;
avctx->coded_frame = avcodec_alloc_frame();
if (!avctx->coded_frame)
return AVERROR(ENOMEM);
return 0;
}
static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
AVPacket *avpkt)
{
int h, w;
AVFrame *pic = avctx->coded_frame;
const uint8_t *src = avpkt->data;
uint8_t *Y1, *Y2, *U, *V;
int ret;
if (pic->data[0])
avctx->release_buffer(avctx, pic);
if (avpkt->size < avctx->width * avctx->height * 3 / 2 + 16) {
av_log(avctx, AV_LOG_ERROR, "packet too small\n");
return AVERROR_INVALIDDATA;
}
pic->reference = 0;
if ((ret = avctx->get_buffer(avctx, pic)) < 0)
return ret;
pic->pict_type = AV_PICTURE_TYPE_I;
pic->key_frame = 1;
if (AV_RL32(src) != 0x01000002) {
av_log_ask_for_sample(avctx, "Unknown frame header %X\n", AV_RL32(src));
return AVERROR_PATCHWELCOME;
}
src += 16;
Y1 = pic->data[0];
Y2 = pic->data[0] + pic->linesize[0];
U = pic->data[1];
V = pic->data[2];
for (h = 0; h < avctx->height; h += 2) {
for (w = 0; w < avctx->width; w += 2) {
AV_WN16A(Y1 + w, AV_RN16A(src));
AV_WN16A(Y2 + w, AV_RN16A(src + 2));
U[w >> 1] = src[4] + 0x80;
V[w >> 1] = src[5] + 0x80;
src += 6;
}
Y1 += pic->linesize[0] << 1;
Y2 += pic->linesize[0] << 1;
U += pic->linesize[1];
V += pic->linesize[2];
}
*data_size = sizeof(AVFrame);
*(AVFrame*)data = *pic;
return avpkt->size;
}
static av_cold int decode_close(AVCodecContext *avctx)
{
AVFrame *pic = avctx->coded_frame;
if (pic->data[0])
avctx->release_buffer(avctx, pic);
av_freep(&avctx->coded_frame);
return 0;
}
AVCodec ff_dxtory_decoder = {
.name = "dxtory",
.long_name = NULL_IF_CONFIG_SMALL("Dxtory"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_DXTORY,
.init = decode_init,
.close = decode_close,
.decode = decode_frame,
.capabilities = CODEC_CAP_DR1,
};