FFmpeg
lclenc.c
Go to the documentation of this file.
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 #include <stdio.h>
41 #include <stdlib.h>
42 
43 #include "libavutil/avassert.h"
44 #include "avcodec.h"
45 #include "internal.h"
46 #include "lcl.h"
47 #include "libavutil/internal.h"
48 #include "libavutil/mem.h"
49 
50 #include <zlib.h>
51 
52 typedef struct LclEncContext {
53 
55 
56  // Image type
57  int imgtype;
58  // Compression type
60  // Flags
61  int flags;
62  z_stream zstream;
64 
66  const AVFrame *p, int *got_packet)
67 {
68  LclEncContext *c = avctx->priv_data;
69  int i, ret;
70  int zret; // Zlib return code
71  int max_size = deflateBound(&c->zstream, avctx->width * avctx->height * 3);
72 
73  if ((ret = ff_alloc_packet2(avctx, pkt, max_size, 0)) < 0)
74  return ret;
75 
76  if(avctx->pix_fmt != AV_PIX_FMT_BGR24){
77  av_log(avctx, AV_LOG_ERROR, "Format not supported!\n");
78  return -1;
79  }
80 
81  zret = deflateReset(&c->zstream);
82  if (zret != Z_OK) {
83  av_log(avctx, AV_LOG_ERROR, "Deflate reset error: %d\n", zret);
84  return -1;
85  }
86  c->zstream.next_out = pkt->data;
87  c->zstream.avail_out = pkt->size;
88 
89  for(i = avctx->height - 1; i >= 0; i--) {
90  c->zstream.next_in = p->data[0]+p->linesize[0]*i;
91  c->zstream.avail_in = avctx->width*3;
92  zret = deflate(&c->zstream, Z_NO_FLUSH);
93  if (zret != Z_OK) {
94  av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
95  return -1;
96  }
97  }
98  zret = deflate(&c->zstream, Z_FINISH);
99  if (zret != Z_STREAM_END) {
100  av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
101  return -1;
102  }
103 
104  pkt->size = c->zstream.total_out;
105  pkt->flags |= AV_PKT_FLAG_KEY;
106  *got_packet = 1;
107 
108  return 0;
109 }
110 
112 {
113  LclEncContext *c = avctx->priv_data;
114  int zret; // Zlib return code
115 
116  c->avctx= avctx;
117 
118  av_assert0(avctx->width && avctx->height);
119 
121  if (!avctx->extradata)
122  return AVERROR(ENOMEM);
123 
124 #if FF_API_CODED_FRAME
127  avctx->coded_frame->key_frame = 1;
129 #endif
130 
133  av_clip(avctx->compression_level, 0, 9);
134  c->flags = 0;
135  c->imgtype = IMGTYPE_RGB24;
136  avctx->bits_per_coded_sample= 24;
137 
138  avctx->extradata[0]= 4;
139  avctx->extradata[1]= 0;
140  avctx->extradata[2]= 0;
141  avctx->extradata[3]= 0;
142  avctx->extradata[4]= c->imgtype;
143  avctx->extradata[5]= c->compression;
144  avctx->extradata[6]= c->flags;
145  avctx->extradata[7]= CODEC_ZLIB;
146  c->avctx->extradata_size= 8;
147 
148  c->zstream.zalloc = Z_NULL;
149  c->zstream.zfree = Z_NULL;
150  c->zstream.opaque = Z_NULL;
151  zret = deflateInit(&c->zstream, c->compression);
152  if (zret != Z_OK) {
153  av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret);
154  return AVERROR_UNKNOWN;
155  }
156 
157  return 0;
158 }
159 
161 {
162  LclEncContext *c = avctx->priv_data;
163 
164  av_freep(&avctx->extradata);
165  deflateEnd(&c->zstream);
166 
167  return 0;
168 }
169 
171  .name = "zlib",
172  .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
173  .type = AVMEDIA_TYPE_VIDEO,
174  .id = AV_CODEC_ID_ZLIB,
175  .priv_data_size = sizeof(LclEncContext),
176  .init = encode_init,
177  .encode2 = encode_frame,
178  .close = encode_end,
181  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
183 };
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:48
#define FF_COMPRESSION_DEFAULT
Definition: avcodec.h:1638
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
Memory handling functions.
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
static av_cold int encode_end(AVCodecContext *avctx)
Definition: lclenc.c:160
int size
Definition: avcodec.h:1478
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
static av_cold int encode_init(AVCodecContext *avctx)
Definition: lclenc.c:111
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:236
static AVPacket pkt
int compression
Definition: lclenc.c:59
AVCodec.
Definition: avcodec.h:3481
#define AV_CODEC_CAP_INTRA_ONLY
Codec is intra only.
Definition: avcodec.h:1067
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:32
static int encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *p, int *got_packet)
Definition: lclenc.c:65
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:40
int imgtype
Definition: lclenc.c:57
#define av_cold
Definition: attributes.h:82
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVCodec ff_zlib_encoder
Definition: lclenc.c:170
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1666
#define COMP_ZLIB_NORMAL
Definition: lcl.h:39
uint8_t * data
Definition: avcodec.h:1477
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2789
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1509
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int flags
Definition: lclenc.c:61
#define CODEC_ZLIB
Definition: lcl.h:47
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
#define IMGTYPE_RGB24
Definition: lcl.h:30
simple assert() macros that are a bit more flexible than ISO C assert().
const char * name
Name of the codec implementation.
Definition: avcodec.h:3488
#define AV_CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: avcodec.h:1037
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1483
AVCodecContext * avctx
Definition: lclenc.c:54
common internal API header
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
int width
picture width / height.
Definition: avcodec.h:1738
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
z_stream zstream
Definition: lclenc.c:62
Libavcodec external API header.
int compression_level
Definition: avcodec.h:1637
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
main external API structure.
Definition: avcodec.h:1565
int extradata_size
Definition: avcodec.h:1667
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:275
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
common internal api header.
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2815
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
static void deflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord, int maxc)
Definition: vf_neighbor.c:164
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:790
void * priv_data
Definition: avcodec.h:1592
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:85
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
#define av_freep(p)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: avcodec.h:1454