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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 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
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 "libavutil/avassert.h"
45 #include "avcodec.h"
46 #include "internal.h"
47 #include "lcl.h"
48 #include "libavutil/internal.h"
49 #include "libavutil/mem.h"
50 
51 #include <zlib.h>
52 
53 /*
54  * Decoder context
55  */
56 typedef struct LclEncContext {
57 
60 
61  // Image type
62  int imgtype;
63  // Compression type
65  // Flags
66  int flags;
67  z_stream zstream;
69 
70 /*
71  *
72  * Encode a frame
73  *
74  */
76  const AVFrame *pict, int *got_packet)
77 {
78  LclEncContext *c = avctx->priv_data;
79  AVFrame * const p = &c->pic;
80  int i, ret;
81  int zret; // Zlib return code
82  int max_size = deflateBound(&c->zstream, avctx->width * avctx->height * 3);
83 
84  if ((ret = ff_alloc_packet2(avctx, pkt, max_size)) < 0)
85  return ret;
86 
87  *p = *pict;
89  p->key_frame= 1;
90 
91  if(avctx->pix_fmt != AV_PIX_FMT_BGR24){
92  av_log(avctx, AV_LOG_ERROR, "Format not supported!\n");
93  return -1;
94  }
95 
96  zret = deflateReset(&c->zstream);
97  if (zret != Z_OK) {
98  av_log(avctx, AV_LOG_ERROR, "Deflate reset error: %d\n", zret);
99  return -1;
100  }
101  c->zstream.next_out = pkt->data;
102  c->zstream.avail_out = pkt->size;
103 
104  for(i = avctx->height - 1; i >= 0; i--) {
105  c->zstream.next_in = p->data[0]+p->linesize[0]*i;
106  c->zstream.avail_in = avctx->width*3;
107  zret = deflate(&c->zstream, Z_NO_FLUSH);
108  if (zret != Z_OK) {
109  av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
110  return -1;
111  }
112  }
113  zret = deflate(&c->zstream, Z_FINISH);
114  if (zret != Z_STREAM_END) {
115  av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
116  return -1;
117  }
118 
119  pkt->size = c->zstream.total_out;
120  pkt->flags |= AV_PKT_FLAG_KEY;
121  *got_packet = 1;
122 
123  return 0;
124 }
125 
126 /*
127  *
128  * Init lcl encoder
129  *
130  */
132 {
133  LclEncContext *c = avctx->priv_data;
134  int zret; // Zlib return code
135 
136  c->avctx= avctx;
137 
138  av_assert0(avctx->width && avctx->height);
139 
140  avctx->extradata= av_mallocz(8);
141  avctx->coded_frame= &c->pic;
142 
145  av_clip(avctx->compression_level, 0, 9);
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 };