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;
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  c->compression = avctx->compression_level == FF_COMPRESSION_DEFAULT ?
126  av_clip(avctx->compression_level, 0, 9);
127  c->flags = 0;
128  c->imgtype = IMGTYPE_RGB24;
129  avctx->bits_per_coded_sample= 24;
130 
131  avctx->extradata[0]= 4;
132  avctx->extradata[1]= 0;
133  avctx->extradata[2]= 0;
134  avctx->extradata[3]= 0;
135  avctx->extradata[4]= c->imgtype;
136  avctx->extradata[5]= c->compression;
137  avctx->extradata[6]= c->flags;
138  avctx->extradata[7]= CODEC_ZLIB;
139  c->avctx->extradata_size= 8;
140 
141  c->zstream.zalloc = Z_NULL;
142  c->zstream.zfree = Z_NULL;
143  c->zstream.opaque = Z_NULL;
144  zret = deflateInit(&c->zstream, c->compression);
145  if (zret != Z_OK) {
146  av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret);
147  return AVERROR_UNKNOWN;
148  }
149 
150  return 0;
151 }
152 
154 {
155  LclEncContext *c = avctx->priv_data;
156 
157  deflateEnd(&c->zstream);
158 
159  return 0;
160 }
161 
163  .name = "zlib",
164  .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
165  .type = AVMEDIA_TYPE_VIDEO,
166  .id = AV_CODEC_ID_ZLIB,
167  .priv_data_size = sizeof(LclEncContext),
168  .init = encode_init,
169  .encode2 = encode_frame,
170  .close = encode_end,
171  .capabilities = AV_CODEC_CAP_FRAME_THREADS,
173  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
175 };
AVCodec
AVCodec.
Definition: codec.h:197
FF_CODEC_CAP_INIT_THREADSAFE
#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:41
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
av_clip
#define av_clip
Definition: common.h:122
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
AVERROR
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
CODEC_ZLIB
#define CODEC_ZLIB
Definition: lcl.h:47
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:365
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
AVERROR_UNKNOWN
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
FF_COMPRESSION_DEFAULT
#define FF_COMPRESSION_DEFAULT
Definition: avcodec.h:574
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:396
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:317
lcl.h
ff_zlib_encoder
const AVCodec ff_zlib_encoder
Definition: lclenc.c:162
LclEncContext::imgtype
int imgtype
Definition: lclenc.c:57
avassert.h
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:181
av_cold
#define av_cold
Definition: attributes.h:90
LclEncContext::flags
int flags
Definition: lclenc.c:61
COMP_ZLIB_NORMAL
#define COMP_ZLIB_NORMAL
Definition: lcl.h:39
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
pix_fmts
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:289
IMGTYPE_RGB24
#define IMGTYPE_RGB24
Definition: lcl.h:30
AV_CODEC_CAP_FRAME_THREADS
#define AV_CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: codec.h:108
AV_CODEC_ID_ZLIB
@ AV_CODEC_ID_ZLIB
Definition: codec_id.h:103
deflate
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:165
c
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
LclEncContext::compression
int compression
Definition: lclenc.c:59
AVPacket::size
int size
Definition: packet.h:366
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:371
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1524
i
int i
Definition: input.c:407
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:602
FF_CODEC_CAP_INIT_CLEANUP
#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:49
internal.h
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:243
LclEncContext::zstream
z_stream zstream
Definition: lclenc.c:62
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:204
LclEncContext
Definition: lclenc.c:52
AVCodecContext::height
int height
Definition: avcodec.h:674
encode_end
static av_cold int encode_end(AVCodecContext *avctx)
Definition: lclenc.c:153
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:711
avcodec.h
LclEncContext::avctx
AVCodecContext * avctx
Definition: lclenc.c:54
ret
ret
Definition: filter_design.txt:187
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: avcodec.h:192
AVCodecContext
main external API structure.
Definition: avcodec.h:501
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
mem.h
encode_frame
static int encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *p, int *got_packet)
Definition: lclenc.c:65
encode_init
static av_cold int encode_init(AVCodecContext *avctx)
Definition: lclenc.c:111
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:528
AVPacket
This structure stores compressed data.
Definition: packet.h:342
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:674
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:334
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
ff_alloc_packet2
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:33
AVCodecContext::compression_level
int compression_level
Definition: avcodec.h:573