lclenc.c 4.3 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
/*
 * 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
 */

/**
23
 * @file
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53
 * 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 <zlib.h>

/*
 * Decoder context
 */
typedef struct LclEncContext {

54 55
    AVCodecContext *avctx;
    AVFrame pic;
56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78

    // Image type
    int imgtype;
    // Compression type
    int compression;
    // Flags
    int flags;
    z_stream zstream;
} 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

    *p = *pict;
79
    p->pict_type= AV_PICTURE_TYPE_I;
80 81 82 83 84 85 86
    p->key_frame= 1;

    if(avctx->pix_fmt != PIX_FMT_BGR24){
        av_log(avctx, AV_LOG_ERROR, "Format not supported!\n");
        return -1;
    }

87
    zret = deflateReset(&c->zstream);
88 89 90 91
    if (zret != Z_OK) {
        av_log(avctx, AV_LOG_ERROR, "Deflate reset error: %d\n", zret);
        return -1;
    }
92 93
    c->zstream.next_out = buf;
    c->zstream.avail_out = buf_size;
94 95 96 97

    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;
98
        zret = deflate(&c->zstream, Z_NO_FLUSH);
99 100 101 102 103
        if (zret != Z_OK) {
            av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
            return -1;
        }
    }
104
    zret = deflate(&c->zstream, Z_FINISH);
105 106 107 108 109 110 111 112 113 114 115 116 117
    if (zret != Z_STREAM_END) {
        av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
        return -1;
    }

    return c->zstream.total_out;
}

/*
 *
 * Init lcl encoder
 *
 */
118
static av_cold int encode_init(AVCodecContext *avctx)
119 120 121 122 123 124 125 126 127 128 129 130 131 132
{
    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;
133 134
    c->imgtype = IMGTYPE_RGB24;
    avctx->bits_per_coded_sample= 24;
135

136 137 138 139 140 141 142 143
    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;
144 145 146 147 148
    c->avctx->extradata_size= 8;

    c->zstream.zalloc = Z_NULL;
    c->zstream.zfree = Z_NULL;
    c->zstream.opaque = Z_NULL;
149
    zret = deflateInit(&c->zstream, c->compression);
150 151 152 153 154 155 156 157 158 159 160 161 162
    if (zret != Z_OK) {
        av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret);
        return 1;
    }

    return 0;
}

/*
 *
 * Uninit lcl encoder
 *
 */
163
static av_cold int encode_end(AVCodecContext *avctx)
164 165 166 167
{
    LclEncContext *c = avctx->priv_data;

    av_freep(&avctx->extradata);
168
    deflateEnd(&c->zstream);
169 170 171 172

    return 0;
}

173
AVCodec ff_zlib_encoder = {
174
    "zlib",
175
    AVMEDIA_TYPE_VIDEO,
176 177 178 179 180
    CODEC_ID_ZLIB,
    sizeof(LclEncContext),
    encode_init,
    encode_frame,
    encode_end,
181
    .pix_fmts = (const enum PixelFormat[]) { PIX_FMT_BGR24, PIX_FMT_NONE },
182
    .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
183
};