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/*
* ZeroCodec Decoder
*
* Copyright (c) 2012, Derek Buitenhuis
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <zlib.h>
#include "avcodec.h"
typedef struct {
AVFrame previous_frame;
z_stream zstream;
int size;
} ZeroCodecContext;
static int zerocodec_decode_frame(AVCodecContext *avctx, void *data,
int *data_size, AVPacket *avpkt)
{
ZeroCodecContext *zc = avctx->priv_data;
AVFrame *pic = avctx->coded_frame;
AVFrame *prev_pic = &zc->previous_frame;
z_stream *zstream = &zc->zstream;
uint8_t *prev = prev_pic->data[0];
uint8_t *dst;
int i, j, zret;
pic->reference = 3;
if (avpkt->flags & AV_PKT_FLAG_KEY) {
pic->key_frame = 1;
pic->pict_type = AV_PICTURE_TYPE_I;
} else {
if (!prev) {
av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
return AVERROR_INVALIDDATA;
}
pic->key_frame = 0;
pic->pict_type = AV_PICTURE_TYPE_P;
}
zret = inflateReset(zstream);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret);
return AVERROR_INVALIDDATA;
}
if (avctx->get_buffer(avctx, pic) < 0) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n");
return AVERROR(ENOMEM);
}
zstream->next_in = avpkt->data;
zstream->avail_in = avpkt->size;
dst = pic->data[0];
/**
* ZeroCodec has very simple interframe compression. If a value
* is the same as the previous frame, set it to 0.
*/
for (i = 0; i < avctx->height; i++) {
zstream->next_out = dst;
zstream->avail_out = avctx->width << 1;
zret = inflate(zstream, Z_SYNC_FLUSH);
if (zret != Z_OK && zret != Z_STREAM_END) {
avctx->release_buffer(avctx, pic);
av_log(avctx, AV_LOG_ERROR,
"Inflate failed with return code: %d.\n", zret);
return AVERROR_INVALIDDATA;
}
if (!(avpkt->flags & AV_PKT_FLAG_KEY))
for (j = 0; j < avctx->width << 1; j++)
dst[j] += prev[j] & -!dst[j];
prev += prev_pic->linesize[0];
dst += pic->linesize[0];
}
/* Release the previous buffer if need be */
if (prev_pic->data[0])
avctx->release_buffer(avctx, prev_pic);
*data_size = sizeof(AVFrame);
*(AVFrame *)data = *pic;
/* Store the previous frame for use later.
* FFSWAP ensures that e.g. pic->data is NULLed. */
FFSWAP(AVFrame, *pic, *prev_pic);
return avpkt->size;
}
static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
{
ZeroCodecContext *zc = avctx->priv_data;
AVFrame *prev_pic = &zc->previous_frame;
inflateEnd(&zc->zstream);
/* Release last frame */
if (prev_pic->data[0])
avctx->release_buffer(avctx, prev_pic);
av_freep(&avctx->coded_frame);
return 0;
}
static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
{
ZeroCodecContext *zc = avctx->priv_data;
z_stream *zstream = &zc->zstream;
int zret;
avctx->pix_fmt = PIX_FMT_UYVY422;
avctx->bits_per_raw_sample = 8;
zc->size = avpicture_get_size(avctx->pix_fmt,
avctx->width, avctx->height);
zstream->zalloc = Z_NULL;
zstream->zfree = Z_NULL;
zstream->opaque = Z_NULL;
zret = inflateInit(zstream);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d.\n", zret);
return AVERROR(ENOMEM);
}
avctx->coded_frame = avcodec_alloc_frame();
if (!avctx->coded_frame) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate frame buffer.\n");
zerocodec_decode_close(avctx);
return AVERROR(ENOMEM);
}
return 0;
}
AVCodec ff_zerocodec_decoder = {
.type = AVMEDIA_TYPE_VIDEO,
.name = "zerocodec",
.id = AV_CODEC_ID_ZEROCODEC,
.priv_data_size = sizeof(ZeroCodecContext),
.init = zerocodec_decode_init,
.decode = zerocodec_decode_frame,
.close = zerocodec_decode_close,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"),
};
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