libavcodec/lclenc.c

   1 /*
   2  * LCL (LossLess Codec Library) Codec
   3  * Copyright (c) 2002-2004 Roberto Togni
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file libavcodec/lclenc.c
  24  * LCL (LossLess Codec Library) Video Codec
  25  * Decoder for MSZH and ZLIB codecs
  26  * Experimental encoder for ZLIB RGB24
  27  *
  28  * Fourcc: MSZH, ZLIB
  29  *
  30  * Original Win32 dll:
  31  * Ver2.23 By Kenji Oshima 2000.09.20
  32  * avimszh.dll, avizlib.dll
  33  *
  34  * A description of the decoding algorithm can be found here:
  35  *   http://www.pcisys.net/~melanson/codecs
  36  *
  37  * Supports: BGR24 (RGB 24bpp)
  38  *
  39  */
  40
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43
  44 #include "avcodec.h"
  45 #include "lcl.h"
  46
  47 #include <zlib.h>
  48
  49 /*
  50  * Decoder context
  51  */
  52 typedef struct LclEncContext {
  53
  54     AVCodecContext *avctx;
  55     AVFrame pic;
  56
  57     // Image type
  58     int imgtype;
  59     // Compression type
  60     int compression;
  61     // Flags
  62     int flags;
  63     z_stream zstream;
  64 } LclEncContext;
  65
  66 /*
  67  *
  68  * Encode a frame
  69  *
  70  */
  71 static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
  72     LclEncContext *c = avctx->priv_data;
  73     AVFrame *pict = data;
  74     AVFrame * const p = &c->pic;
  75     int i;
  76     int zret; // Zlib return code
  77
  78     *p = *pict;
  79     p->pict_type= FF_I_TYPE;
  80     p->key_frame= 1;
  81
  82     if(avctx->pix_fmt != PIX_FMT_BGR24){
  83         av_log(avctx, AV_LOG_ERROR, "Format not supported!\n");
  84         return -1;
  85     }
  86
  87     zret = deflateReset(&c->zstream);
  88     if (zret != Z_OK) {
  89         av_log(avctx, AV_LOG_ERROR, "Deflate reset error: %d\n", zret);
  90         return -1;
  91     }
  92     c->zstream.next_out = buf;
  93     c->zstream.avail_out = buf_size;
  94
  95     for(i = avctx->height - 1; i >= 0; i--) {
  96         c->zstream.next_in = p->data[0]+p->linesize[0]*i;
  97         c->zstream.avail_in = avctx->width*3;
  98         zret = deflate(&c->zstream, Z_NO_FLUSH);
  99         if (zret != Z_OK) {
 100             av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
 101             return -1;
 102         }
 103     }
 104     zret = deflate(&c->zstream, Z_FINISH);
 105     if (zret != Z_STREAM_END) {
 106         av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
 107         return -1;
 108     }
 109
 110     return c->zstream.total_out;
 111 }
 112
 113 /*
 114  *
 115  * Init lcl encoder
 116  *
 117  */
 118 static av_cold int encode_init(AVCodecContext *avctx)
 119 {
 120     LclEncContext *c = avctx->priv_data;
 121     int zret; // Zlib return code
 122
 123     c->avctx= avctx;
 124
 125     assert(avctx->width && avctx->height);
 126
 127     avctx->extradata= av_mallocz(8);
 128     avctx->coded_frame= &c->pic;
 129
 130     // Will be user settable someday
 131     c->compression = 6;
 132     c->flags = 0;
 133
 134     switch(avctx->pix_fmt){
 135         case PIX_FMT_BGR24:
 136             c->imgtype = IMGTYPE_RGB24;
 137             avctx->bits_per_coded_sample= 24;
 138             break;
 139         default:
 140             av_log(avctx, AV_LOG_ERROR, "Input pixel format %s not supported\n", avcodec_get_pix_fmt_name(avctx->pix_fmt));
 141             return -1;
 142     }
 143
 144     avctx->extradata[0]= 4;
 145     avctx->extradata[1]= 0;
 146     avctx->extradata[2]= 0;
 147     avctx->extradata[3]= 0;
 148     avctx->extradata[4]= c->imgtype;
 149     avctx->extradata[5]= c->compression;
 150     avctx->extradata[6]= c->flags;
 151     avctx->extradata[7]= CODEC_ZLIB;
 152     c->avctx->extradata_size= 8;
 153
 154     c->zstream.zalloc = Z_NULL;
 155     c->zstream.zfree = Z_NULL;
 156     c->zstream.opaque = Z_NULL;
 157     zret = deflateInit(&c->zstream, c->compression);
 158     if (zret != Z_OK) {
 159         av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret);
 160         return 1;
 161     }
 162
 163     return 0;
 164 }
 165
 166 /*
 167  *
 168  * Uninit lcl encoder
 169  *
 170  */
 171 static av_cold int encode_end(AVCodecContext *avctx)
 172 {
 173     LclEncContext *c = avctx->priv_data;
 174
 175     av_freep(&avctx->extradata);
 176     deflateEnd(&c->zstream);
 177
 178     return 0;
 179 }
 180
 181 AVCodec zlib_encoder = {
 182     "zlib",
 183     CODEC_TYPE_VIDEO,
 184     CODEC_ID_ZLIB,
 185     sizeof(LclEncContext),
 186     encode_init,
 187     encode_frame,
 188     encode_end,
 189     .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
 190 };