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 #include "libavutil/internal.h"
47 #include "libavutil/mem.h"
48 
49 #include <zlib.h>
50 
51 /*
52  * Decoder context
53  */
54 typedef struct LclEncContext {
55 
58 
59  // Image type
60  int imgtype;
61  // Compression type
63  // Flags
64  int flags;
65  z_stream zstream;
67 
68 /*
69  *
70  * Encode a frame
71  *
72  */
73 static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
74  const AVFrame *pict, int *got_packet)
75 {
76  LclEncContext *c = avctx->priv_data;
77  AVFrame * const p = &c->pic;
78  int i, ret;
79  int zret; // Zlib return code
80  int max_size = deflateBound(&c->zstream, avctx->width * avctx->height * 3);
81 
82  if (!pkt->data &&
83  (ret = av_new_packet(pkt, max_size)) < 0) {
84  av_log(avctx, AV_LOG_ERROR, "Error allocating packet of size %d.\n", max_size);
85  return ret;
86  }
87 
88  *p = *pict;
90  p->key_frame= 1;
91 
92  if(avctx->pix_fmt != AV_PIX_FMT_BGR24){
93  av_log(avctx, AV_LOG_ERROR, "Format not supported!\n");
94  return -1;
95  }
96 
97  zret = deflateReset(&c->zstream);
98  if (zret != Z_OK) {
99  av_log(avctx, AV_LOG_ERROR, "Deflate reset error: %d\n", zret);
100  return -1;
101  }
102  c->zstream.next_out = pkt->data;
103  c->zstream.avail_out = pkt->size;
104 
105  for(i = avctx->height - 1; i >= 0; i--) {
106  c->zstream.next_in = p->data[0]+p->linesize[0]*i;
107  c->zstream.avail_in = avctx->width*3;
108  zret = deflate(&c->zstream, Z_NO_FLUSH);
109  if (zret != Z_OK) {
110  av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
111  return -1;
112  }
113  }
114  zret = deflate(&c->zstream, Z_FINISH);
115  if (zret != Z_STREAM_END) {
116  av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
117  return -1;
118  }
119 
120  pkt->size = c->zstream.total_out;
121  pkt->flags |= AV_PKT_FLAG_KEY;
122  *got_packet = 1;
123 
124  return 0;
125 }
126 
127 /*
128  *
129  * Init lcl encoder
130  *
131  */
133 {
134  LclEncContext *c = avctx->priv_data;
135  int zret; // Zlib return code
136 
137  c->avctx= avctx;
138 
139  assert(avctx->width && avctx->height);
140 
141  avctx->extradata= av_mallocz(8);
142  avctx->coded_frame= &c->pic;
143 
144  // Will be user settable someday
145  c->compression = 6;
146  c->flags = 0;
147  c->imgtype = IMGTYPE_RGB24;
148  avctx->bits_per_coded_sample= 24;
149 
150  avctx->extradata[0]= 4;
151  avctx->extradata[1]= 0;
152  avctx->extradata[2]= 0;
153  avctx->extradata[3]= 0;
154  avctx->extradata[4]= c->imgtype;
155  avctx->extradata[5]= c->compression;
156  avctx->extradata[6]= c->flags;
157  avctx->extradata[7]= CODEC_ZLIB;
158  c->avctx->extradata_size= 8;
159 
160  c->zstream.zalloc = Z_NULL;
161  c->zstream.zfree = Z_NULL;
162  c->zstream.opaque = Z_NULL;
163  zret = deflateInit(&c->zstream, c->compression);
164  if (zret != Z_OK) {
165  av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret);
166  return 1;
167  }
168 
169  return 0;
170 }
171 
172 /*
173  *
174  * Uninit lcl encoder
175  *
176  */
178 {
179  LclEncContext *c = avctx->priv_data;
180 
181  av_freep(&avctx->extradata);
182  deflateEnd(&c->zstream);
183 
184  return 0;
185 }
186 
188  .name = "zlib",
189  .type = AVMEDIA_TYPE_VIDEO,
190  .id = AV_CODEC_ID_ZLIB,
191  .priv_data_size = sizeof(LclEncContext),
192  .init = encode_init,
193  .encode2 = encode_frame,
194  .close = encode_end,
195  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
196  .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
197 };