ffmpeg/libavcodec/lclenc.c

198 lines
4.9 KiB
C

/*
* LCL (LossLess Codec Library) Codec
* Copyright (c) 2002-2004 Roberto Togni
*
* 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
*/
/**
* @file
* LCL (LossLess Codec Library) Video Codec
* Decoder for MSZH and ZLIB codecs
* Experimental encoder for ZLIB RGB24
*
* Fourcc: MSZH, ZLIB
*
* Original Win32 dll:
* Ver2.23 By Kenji Oshima 2000.09.20
* avimszh.dll, avizlib.dll
*
* A description of the decoding algorithm can be found here:
* http://www.pcisys.net/~melanson/codecs
*
* Supports: BGR24 (RGB 24bpp)
*
*/
#include <stdio.h>
#include <stdlib.h>
#include "avcodec.h"
#include "lcl.h"
#include "libavutil/internal.h"
#include "libavutil/mem.h"
#include <zlib.h>
/*
* Decoder context
*/
typedef struct LclEncContext {
AVCodecContext *avctx;
AVFrame pic;
// Image type
int imgtype;
// Compression type
int compression;
// Flags
int flags;
z_stream zstream;
} LclEncContext;
/*
*
* Encode a frame
*
*/
static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
const AVFrame *pict, int *got_packet)
{
LclEncContext *c = avctx->priv_data;
AVFrame * const p = &c->pic;
int i, ret;
int zret; // Zlib return code
int max_size = deflateBound(&c->zstream, avctx->width * avctx->height * 3);
if (!pkt->data &&
(ret = av_new_packet(pkt, max_size)) < 0) {
av_log(avctx, AV_LOG_ERROR, "Error allocating packet of size %d.\n", max_size);
return ret;
}
*p = *pict;
p->pict_type= AV_PICTURE_TYPE_I;
p->key_frame= 1;
if(avctx->pix_fmt != AV_PIX_FMT_BGR24){
av_log(avctx, AV_LOG_ERROR, "Format not supported!\n");
return -1;
}
zret = deflateReset(&c->zstream);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Deflate reset error: %d\n", zret);
return -1;
}
c->zstream.next_out = pkt->data;
c->zstream.avail_out = pkt->size;
for(i = avctx->height - 1; i >= 0; i--) {
c->zstream.next_in = p->data[0]+p->linesize[0]*i;
c->zstream.avail_in = avctx->width*3;
zret = deflate(&c->zstream, Z_NO_FLUSH);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
return -1;
}
}
zret = deflate(&c->zstream, Z_FINISH);
if (zret != Z_STREAM_END) {
av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
return -1;
}
pkt->size = c->zstream.total_out;
pkt->flags |= AV_PKT_FLAG_KEY;
*got_packet = 1;
return 0;
}
/*
*
* Init lcl encoder
*
*/
static av_cold int encode_init(AVCodecContext *avctx)
{
LclEncContext *c = avctx->priv_data;
int zret; // Zlib return code
c->avctx= avctx;
assert(avctx->width && avctx->height);
avctx->extradata= av_mallocz(8);
avctx->coded_frame= &c->pic;
// Will be user settable someday
c->compression = 6;
c->flags = 0;
c->imgtype = IMGTYPE_RGB24;
avctx->bits_per_coded_sample= 24;
avctx->extradata[0]= 4;
avctx->extradata[1]= 0;
avctx->extradata[2]= 0;
avctx->extradata[3]= 0;
avctx->extradata[4]= c->imgtype;
avctx->extradata[5]= c->compression;
avctx->extradata[6]= c->flags;
avctx->extradata[7]= CODEC_ZLIB;
c->avctx->extradata_size= 8;
c->zstream.zalloc = Z_NULL;
c->zstream.zfree = Z_NULL;
c->zstream.opaque = Z_NULL;
zret = deflateInit(&c->zstream, c->compression);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret);
return 1;
}
return 0;
}
/*
*
* Uninit lcl encoder
*
*/
static av_cold int encode_end(AVCodecContext *avctx)
{
LclEncContext *c = avctx->priv_data;
av_freep(&avctx->extradata);
deflateEnd(&c->zstream);
return 0;
}
AVCodec ff_zlib_encoder = {
.name = "zlib",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_ZLIB,
.priv_data_size = sizeof(LclEncContext),
.init = encode_init,
.encode2 = encode_frame,
.close = encode_end,
.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
.long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
};