FFmpeg
cscd.c
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1 /*
2  * CamStudio decoder
3  * Copyright (c) 2006 Reimar Doeffinger
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 #include <stdio.h>
22 #include <stdlib.h>
23 
24 #include "avcodec.h"
25 #include "internal.h"
26 #include "libavutil/common.h"
27 
28 #if CONFIG_ZLIB
29 #include <zlib.h>
30 #endif
31 #include "libavutil/lzo.h"
32 
33 typedef struct CamStudioContext {
36  unsigned int decomp_size;
37  unsigned char* decomp_buf;
39 
40 static void copy_frame_default(AVFrame *f, const uint8_t *src,
41  int linelen, int height)
42 {
43  int i, src_stride = FFALIGN(linelen, 4);
44  uint8_t *dst = f->data[0];
45  dst += (height - 1) * f->linesize[0];
46  for (i = height; i; i--) {
47  memcpy(dst, src, linelen);
48  src += src_stride;
49  dst -= f->linesize[0];
50  }
51 }
52 
53 static void add_frame_default(AVFrame *f, const uint8_t *src,
54  int linelen, int height)
55 {
56  int i, j, src_stride = FFALIGN(linelen, 4);
57  uint8_t *dst = f->data[0];
58  dst += (height - 1) * f->linesize[0];
59  for (i = height; i; i--) {
60  for (j = linelen; j; j--)
61  *dst++ += *src++;
62  src += src_stride - linelen;
63  dst -= f->linesize[0] + linelen;
64  }
65 }
66 
67 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
68  AVPacket *avpkt)
69 {
70  const uint8_t *buf = avpkt->data;
71  int buf_size = avpkt->size;
72  CamStudioContext *c = avctx->priv_data;
73  int ret;
74 
75  if (buf_size < 2) {
76  av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
77  return AVERROR_INVALIDDATA;
78  }
79 
80  if ((ret = ff_reget_buffer(avctx, c->pic, 0)) < 0)
81  return ret;
82 
83  // decompress data
84  switch ((buf[0] >> 1) & 7) {
85  case 0: { // lzo compression
86  int outlen = c->decomp_size, inlen = buf_size - 2;
87  if (av_lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen) || outlen) {
88  av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
89  return AVERROR_INVALIDDATA;
90  }
91  break;
92  }
93  case 1: { // zlib compression
94 #if CONFIG_ZLIB
95  unsigned long dlen = c->decomp_size;
96  if (uncompress(c->decomp_buf, &dlen, &buf[2], buf_size - 2) != Z_OK) {
97  av_log(avctx, AV_LOG_ERROR, "error during zlib decompression\n");
98  return AVERROR_INVALIDDATA;
99  }
100  break;
101 #else
102  av_log(avctx, AV_LOG_ERROR, "compiled without zlib support\n");
103  return AVERROR(ENOSYS);
104 #endif
105  }
106  default:
107  av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
108  return AVERROR_INVALIDDATA;
109  }
110 
111  // flip upside down, add difference frame
112  if (buf[0] & 1) { // keyframe
114  c->pic->key_frame = 1;
116  c->linelen, c->height);
117  } else {
119  c->pic->key_frame = 0;
121  c->linelen, c->height);
122  }
123 
124  *got_frame = 1;
125  if ((ret = av_frame_ref(data, c->pic)) < 0)
126  return ret;
127 
128  return buf_size;
129 }
130 
132 {
133  CamStudioContext *c = avctx->priv_data;
134  int stride;
135  switch (avctx->bits_per_coded_sample) {
136  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555LE; break;
137  case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
138  case 32: avctx->pix_fmt = AV_PIX_FMT_BGR0; break;
139  default:
140  av_log(avctx, AV_LOG_ERROR,
141  "CamStudio codec error: invalid depth %i bpp\n",
142  avctx->bits_per_coded_sample);
143  return AVERROR_INVALIDDATA;
144  }
145  c->bpp = avctx->bits_per_coded_sample;
146  c->linelen = avctx->width * avctx->bits_per_coded_sample / 8;
147  c->height = avctx->height;
148  stride = FFALIGN(c->linelen, 4);
149  c->decomp_size = c->height * stride;
151  if (!c->decomp_buf) {
152  av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
153  return AVERROR(ENOMEM);
154  }
155  c->pic = av_frame_alloc();
156  if (!c->pic)
157  return AVERROR(ENOMEM);
158  return 0;
159 }
160 
162 {
163  CamStudioContext *c = avctx->priv_data;
164  av_freep(&c->decomp_buf);
165  av_frame_free(&c->pic);
166  return 0;
167 }
168 
170  .name = "camstudio",
171  .long_name = NULL_IF_CONFIG_SMALL("CamStudio"),
172  .type = AVMEDIA_TYPE_VIDEO,
173  .id = AV_CODEC_ID_CSCD,
174  .priv_data_size = sizeof(CamStudioContext),
175  .init = decode_init,
176  .close = decode_end,
177  .decode = decode_frame,
178  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
179  .capabilities = AV_CODEC_CAP_DR1,
180 };
#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
static void add_frame_default(AVFrame *f, const uint8_t *src, int linelen, int height)
Definition: cscd.c:53
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
packed RGB 5:5:5, 16bpp, (msb)1X 5R 5G 5B(lsb), little-endian, X=unused/undefined ...
Definition: pixfmt.h:108
int size
Definition: avcodec.h:1481
int height
Definition: cscd.c:35
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
#define src
Definition: vp8dsp.c:254
AVCodec.
Definition: avcodec.h:3492
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
uint8_t
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
#define f(width, name)
Definition: cbs_vp9.c:255
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
static av_cold int decode_end(AVCodecContext *avctx)
Definition: cscd.c:161
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:443
#define AV_LZO_OUTPUT_PADDING
Definition: lzo.h:47
uint8_t * data
Definition: avcodec.h:1480
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2792
#define FFALIGN(x, a)
Definition: macros.h:48
#define av_log(a,...)
#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
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: cscd.c:67
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
unsigned char * decomp_buf
Definition: cscd.c:37
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available...
Definition: decode.c:2015
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
int width
picture width / height.
Definition: avcodec.h:1741
int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen)
Decodes LZO 1x compressed data.
Definition: lzo.c:134
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
AVFrame * pic
Definition: cscd.c:34
Libavcodec external API header.
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:1568
void * buf
Definition: avisynth_c.h:766
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
Definition: pixfmt.h:240
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
common internal api header.
common internal and external API header
void * priv_data
Definition: avcodec.h:1595
static av_cold int decode_init(AVCodecContext *avctx)
Definition: cscd.c:131
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
int linelen
Definition: cscd.c:35
#define av_freep(p)
#define stride
static void copy_frame_default(AVFrame *f, const uint8_t *src, int linelen, int height)
Definition: cscd.c:40
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
This structure stores compressed data.
Definition: avcodec.h:1457
AVCodec ff_cscd_decoder
Definition: cscd.c:169
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:984
for(j=16;j >0;--j)
unsigned int decomp_size
Definition: cscd.c:36
Predicted.
Definition: avutil.h:275