lclenc.c
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1 /*
2  * LCL (LossLess Codec Library) Codec
3  * Copyright (c) 2002-2004 Roberto Togni
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
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 
56 
57  // Image type
58  int imgtype;
59  // Compression type
61  // Flags
62  int flags;
63  z_stream zstream;
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;
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  */
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  c->imgtype = IMGTYPE_RGB24;
134  avctx->bits_per_coded_sample= 24;
135 
136  avctx->extradata[0]= 4;
137  avctx->extradata[1]= 0;
138  avctx->extradata[2]= 0;
139  avctx->extradata[3]= 0;
140  avctx->extradata[4]= c->imgtype;
141  avctx->extradata[5]= c->compression;
142  avctx->extradata[6]= c->flags;
143  avctx->extradata[7]= CODEC_ZLIB;
144  c->avctx->extradata_size= 8;
145 
146  c->zstream.zalloc = Z_NULL;
147  c->zstream.zfree = Z_NULL;
148  c->zstream.opaque = Z_NULL;
149  zret = deflateInit(&c->zstream, c->compression);
150  if (zret != Z_OK) {
151  av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret);
152  return 1;
153  }
154 
155  return 0;
156 }
157 
158 /*
159  *
160  * Uninit lcl encoder
161  *
162  */
164 {
165  LclEncContext *c = avctx->priv_data;
166 
167  av_freep(&avctx->extradata);
168  deflateEnd(&c->zstream);
169 
170  return 0;
171 }
172 
174  .name = "zlib",
175  .type = AVMEDIA_TYPE_VIDEO,
176  .id = CODEC_ID_ZLIB,
177  .priv_data_size = sizeof(LclEncContext),
178  .init = encode_init,
179  .encode = encode_frame,
180  .close = 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 };