ffmpeg/libavcodec/lclenc.c

233 lines
5.7 KiB
C

/*
* LCL (LossLess Codec Library) Codec
* Copyright (c) 2002-2004 Roberto Togni
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file lcl.c
* 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 "bitstream.h"
#include "lcl.h"
#ifdef CONFIG_ZLIB
#include <zlib.h>
#endif
/*
* Decoder context
*/
typedef struct LclEncContext {
AVCodecContext *avctx;
AVFrame pic;
PutBitContext pb;
// Image type
int imgtype;
// Compression type
int compression;
// Flags
int flags;
// Decompressed data size
unsigned int decomp_size;
// Maximum compressed data size
unsigned int max_comp_size;
// Compression buffer
unsigned char* comp_buf;
#ifdef CONFIG_ZLIB
z_stream zstream;
#endif
} LclEncContext;
/*
*
* Encode a frame
*
*/
static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
LclEncContext *c = avctx->priv_data;
AVFrame *pict = data;
AVFrame * const p = &c->pic;
int i;
int zret; // Zlib return code
#ifndef CONFIG_ZLIB
av_log(avctx, AV_LOG_ERROR, "Zlib support not compiled in.\n");
return -1;
#else
init_put_bits(&c->pb, buf, buf_size);
*p = *pict;
p->pict_type= FF_I_TYPE;
p->key_frame= 1;
if(avctx->pix_fmt != 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 = c->comp_buf;
c->zstream.avail_out = c->max_comp_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;
}
for (i = 0; i < c->zstream.total_out; i++)
put_bits(&c->pb, 8, c->comp_buf[i]);
flush_put_bits(&c->pb);
return c->zstream.total_out;
#endif
}
/*
*
* Init lcl encoder
*
*/
static av_cold int encode_init(AVCodecContext *avctx)
{
LclEncContext *c = avctx->priv_data;
int zret; // Zlib return code
#ifndef CONFIG_ZLIB
av_log(avctx, AV_LOG_ERROR, "Zlib support not compiled.\n");
return 1;
#else
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;
switch(avctx->pix_fmt){
case PIX_FMT_BGR24:
c->imgtype = IMGTYPE_RGB24;
c->decomp_size = avctx->width * avctx->height * 3;
avctx->bits_per_sample= 24;
break;
default:
av_log(avctx, AV_LOG_ERROR, "Format %d not supported\n", avctx->pix_fmt);
return -1;
}
((uint8_t*)avctx->extradata)[0]= 4;
((uint8_t*)avctx->extradata)[1]= 0;
((uint8_t*)avctx->extradata)[2]= 0;
((uint8_t*)avctx->extradata)[3]= 0;
((uint8_t*)avctx->extradata)[4]= c->imgtype;
((uint8_t*)avctx->extradata)[5]= c->compression;
((uint8_t*)avctx->extradata)[6]= c->flags;
((uint8_t*)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;
}
/* Conservative upper bound taken from zlib v1.2.1 source */
c->max_comp_size = c->decomp_size + ((c->decomp_size + 7) >> 3) +
((c->decomp_size + 63) >> 6) + 11;
if ((c->comp_buf = av_malloc(c->max_comp_size)) == NULL) {
av_log(avctx, AV_LOG_ERROR, "Can't allocate compression buffer.\n");
return 1;
}
return 0;
#endif
}
/*
*
* Uninit lcl encoder
*
*/
static av_cold int encode_end(AVCodecContext *avctx)
{
LclEncContext *c = avctx->priv_data;
av_freep(&avctx->extradata);
av_freep(&c->comp_buf);
#ifdef CONFIG_ZLIB
deflateEnd(&(c->zstream));
#endif
return 0;
}
AVCodec zlib_encoder = {
"zlib",
CODEC_TYPE_VIDEO,
CODEC_ID_ZLIB,
sizeof(LclEncContext),
encode_init,
encode_frame,
encode_end,
.long_name = "LCL (LossLess Codec Library) ZLIB",
};