FFmpeg
mxpegdec.c
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1 /*
2  * MxPEG decoder
3  * Copyright (c) 2011 Anatoly Nenashev
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 /**
24  * @file
25  * MxPEG decoder
26  */
27 
28 #include "codec_internal.h"
29 #include "decode.h"
30 #include "mjpeg.h"
31 #include "mjpegdec.h"
32 
33 typedef struct MXpegDecodeContext {
35  AVFrame *picture[2]; /* pictures array */
36  int picture_index; /* index of current picture */
37  int got_sof_data; /* true if SOF data successfully parsed */
38  int got_mxm_bitmask; /* true if MXM bitmask available */
39  uint8_t *mxm_bitmask; /* bitmask buffer */
40  unsigned bitmask_size; /* size of bitmask */
41  int has_complete_frame; /* true if has complete frame */
42  uint8_t *completion_bitmask; /* completion bitmask of macroblocks */
43  unsigned mb_width, mb_height; /* size of picture in MB's from MXM header */
45 
47 {
48  MXpegDecodeContext *s = avctx->priv_data;
49  MJpegDecodeContext *jpg = &s->jpg;
50  int i;
51 
52  jpg->picture_ptr = NULL;
53  ff_mjpeg_decode_end(avctx);
54 
55  for (i = 0; i < 2; ++i)
56  av_frame_free(&s->picture[i]);
57 
58  s->bitmask_size = 0;
59  av_freep(&s->mxm_bitmask);
60  av_freep(&s->completion_bitmask);
61 
62  return 0;
63 }
64 
66 {
67  MXpegDecodeContext *s = avctx->priv_data;
68 
69  s->picture[0] = av_frame_alloc();
70  s->picture[1] = av_frame_alloc();
71  if (!s->picture[0] || !s->picture[1])
72  return AVERROR(ENOMEM);
73 
74  s->jpg.picture_ptr = s->picture[0];
75  return ff_mjpeg_decode_init(avctx);
76 }
77 
79  const uint8_t *buf_ptr, int buf_size)
80 {
81  int len;
82  if (buf_size < 2)
83  return 0;
84  len = AV_RB16(buf_ptr);
85  skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
86 
87  return 0;
88 }
89 
91  const uint8_t *buf_ptr, int buf_size)
92 {
93  unsigned bitmask_size, mb_count;
94  int i;
95 
96  s->mb_width = AV_RL16(buf_ptr+4);
97  s->mb_height = AV_RL16(buf_ptr+6);
98  mb_count = s->mb_width * s->mb_height;
99 
100  bitmask_size = (mb_count + 7) >> 3;
101  if (bitmask_size > buf_size - 12) {
102  av_log(s->jpg.avctx, AV_LOG_ERROR,
103  "MXM bitmask is not complete\n");
104  return AVERROR(EINVAL);
105  }
106 
107  if (s->bitmask_size != bitmask_size) {
108  s->bitmask_size = 0;
109  av_freep(&s->mxm_bitmask);
110  s->mxm_bitmask = av_malloc(bitmask_size);
111  if (!s->mxm_bitmask) {
112  av_log(s->jpg.avctx, AV_LOG_ERROR,
113  "MXM bitmask memory allocation error\n");
114  return AVERROR(ENOMEM);
115  }
116 
117  av_freep(&s->completion_bitmask);
118  s->completion_bitmask = av_mallocz(bitmask_size);
119  if (!s->completion_bitmask) {
120  av_log(s->jpg.avctx, AV_LOG_ERROR,
121  "Completion bitmask memory allocation error\n");
122  return AVERROR(ENOMEM);
123  }
124 
125  s->bitmask_size = bitmask_size;
126  }
127 
128  memcpy(s->mxm_bitmask, buf_ptr + 12, bitmask_size);
129  s->got_mxm_bitmask = 1;
130 
131  if (!s->has_complete_frame) {
132  uint8_t completion_check = 0xFF;
133  for (i = 0; i < bitmask_size; ++i) {
134  s->completion_bitmask[i] |= s->mxm_bitmask[i];
135  completion_check &= s->completion_bitmask[i];
136  }
137  s->has_complete_frame = !(completion_check ^ 0xFF);
138  }
139 
140  return 0;
141 }
142 
144  const uint8_t *buf_ptr, int buf_size)
145 {
146  int len, ret = 0;
147  if (buf_size < 2)
148  return 0;
149  len = AV_RB16(buf_ptr);
150  if (len > 14 && len <= buf_size && !strncmp(buf_ptr + 2, "MXM", 3)) {
151  ret = mxpeg_decode_mxm(s, buf_ptr + 2, len - 2);
152  }
153  skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
154 
155  return ret;
156 }
157 
159  AVFrame *reference_ptr)
160 {
161  if ((jpg->width + 0x0F)>>4 != s->mb_width ||
162  (jpg->height + 0x0F)>>4 != s->mb_height) {
163  av_log(jpg->avctx, AV_LOG_ERROR,
164  "Picture dimensions stored in SOF and MXM mismatch\n");
165  return AVERROR(EINVAL);
166  }
167 
168  if (reference_ptr->data[0]) {
169  int i;
170  for (i = 0; i < MAX_COMPONENTS; ++i) {
171  if ( (!reference_ptr->data[i] ^ !jpg->picture_ptr->data[i]) ||
172  reference_ptr->linesize[i] != jpg->picture_ptr->linesize[i]) {
173  av_log(jpg->avctx, AV_LOG_ERROR,
174  "Dimensions of current and reference picture mismatch\n");
175  return AVERROR(EINVAL);
176  }
177  }
178  }
179 
180  return 0;
181 }
182 
183 static int mxpeg_decode_frame(AVCodecContext *avctx, AVFrame *rframe,
184  int *got_frame, AVPacket *avpkt)
185 {
186  const uint8_t *buf = avpkt->data;
187  int buf_size = avpkt->size;
188  MXpegDecodeContext *s = avctx->priv_data;
189  MJpegDecodeContext *jpg = &s->jpg;
190  const uint8_t *buf_end, *buf_ptr;
191  const uint8_t *unescaped_buf_ptr;
192  int unescaped_buf_size;
193  int start_code;
194  int ret;
195 
196  if (avctx->skip_frame == AVDISCARD_ALL)
197  return AVERROR_PATCHWELCOME;
198 
199  buf_ptr = buf;
200  buf_end = buf + buf_size;
201  jpg->got_picture = 0;
202  s->got_mxm_bitmask = 0;
203  s->got_sof_data = !!s->got_sof_data;
204  while (buf_ptr < buf_end) {
205  start_code = ff_mjpeg_find_marker(jpg, &buf_ptr, buf_end,
206  &unescaped_buf_ptr, &unescaped_buf_size);
207  if (start_code < 0)
208  goto the_end;
209  {
210  init_get_bits(&jpg->gb, unescaped_buf_ptr, unescaped_buf_size*8);
211 
212  if (start_code >= APP0 && start_code <= APP15) {
213  mxpeg_decode_app(s, unescaped_buf_ptr, unescaped_buf_size);
214  }
215 
216  switch (start_code) {
217  case SOI:
218  if (jpg->got_picture) //emulating EOI
219  goto the_end;
220  break;
221  case EOI:
222  goto the_end;
223  case DQT:
224  ret = ff_mjpeg_decode_dqt(jpg);
225  if (ret < 0) {
226  av_log(avctx, AV_LOG_ERROR,
227  "quantization table decode error\n");
228  return ret;
229  }
230  break;
231  case DHT:
232  ret = ff_mjpeg_decode_dht(jpg);
233  if (ret < 0) {
234  av_log(avctx, AV_LOG_ERROR,
235  "huffman table decode error\n");
236  return ret;
237  }
238  break;
239  case COM:
240  ret = mxpeg_decode_com(s, unescaped_buf_ptr,
241  unescaped_buf_size);
242  if (ret < 0)
243  return ret;
244  break;
245  case SOF0:
246  if (s->got_sof_data > 1) {
247  av_log(avctx, AV_LOG_ERROR,
248  "Multiple SOF in a frame\n");
249  return AVERROR_INVALIDDATA;
250  }
251  ret = ff_mjpeg_decode_sof(jpg);
252  if (ret < 0) {
253  av_log(avctx, AV_LOG_ERROR,
254  "SOF data decode error\n");
255  s->got_sof_data = 0;
256  return ret;
257  }
258  if (jpg->interlaced) {
259  av_log(avctx, AV_LOG_ERROR,
260  "Interlaced mode not supported in MxPEG\n");
261  s->got_sof_data = 0;
262  return AVERROR(EINVAL);
263  }
264  s->got_sof_data ++;
265  break;
266  case SOS:
267  if (!s->got_sof_data) {
268  av_log(avctx, AV_LOG_WARNING,
269  "Can not process SOS without SOF data, skipping\n");
270  break;
271  }
272  if (!jpg->got_picture) {
273  if (jpg->first_picture) {
274  av_log(avctx, AV_LOG_WARNING,
275  "First picture has no SOF, skipping\n");
276  break;
277  }
278  if (!s->got_mxm_bitmask){
279  av_log(avctx, AV_LOG_WARNING,
280  "Non-key frame has no MXM, skipping\n");
281  break;
282  }
283  /* use stored SOF data to allocate current picture */
285  if ((ret = ff_get_buffer(avctx, jpg->picture_ptr,
287  return ret;
290  jpg->got_picture = 1;
291  } else {
294  }
295 
296  if (s->got_mxm_bitmask) {
297  AVFrame *reference_ptr = s->picture[s->picture_index ^ 1];
298  if (mxpeg_check_dimensions(s, jpg, reference_ptr) < 0)
299  break;
300 
301  /* allocate dummy reference picture if needed */
302  if (!reference_ptr->data[0] &&
303  (ret = ff_get_buffer(avctx, reference_ptr,
305  return ret;
306 
307  ret = ff_mjpeg_decode_sos(jpg, s->mxm_bitmask, s->bitmask_size, reference_ptr);
308  if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
309  return ret;
310  } else {
311  ret = ff_mjpeg_decode_sos(jpg, NULL, 0, NULL);
312  if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
313  return ret;
314  }
315 
316  break;
317  }
318 
319  buf_ptr += (get_bits_count(&jpg->gb)+7) >> 3;
320  }
321 
322  }
323 
324 the_end:
325  if (jpg->got_picture) {
326  int ret = av_frame_ref(rframe, jpg->picture_ptr);
327  if (ret < 0)
328  return ret;
329  *got_frame = 1;
330 
331  s->picture_index ^= 1;
332  jpg->picture_ptr = s->picture[s->picture_index];
333 
334  if (!s->has_complete_frame) {
335  if (!s->got_mxm_bitmask)
336  s->has_complete_frame = 1;
337  else
338  *got_frame = 0;
339  }
340  }
341 
342  return buf_ptr - buf;
343 }
344 
346  .p.name = "mxpeg",
347  CODEC_LONG_NAME("Mobotix MxPEG video"),
348  .p.type = AVMEDIA_TYPE_VIDEO,
349  .p.id = AV_CODEC_ID_MXPEG,
350  .priv_data_size = sizeof(MXpegDecodeContext),
352  .close = mxpeg_decode_end,
354  .p.capabilities = AV_CODEC_CAP_DR1,
355  .p.max_lowres = 3,
356  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
357 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
mjpeg.h
AV_EF_EXPLODE
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: defs.h:51
MJpegDecodeContext::avctx
AVCodecContext * avctx
Definition: mjpegdec.h:56
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: codec_internal.h:42
MJpegDecodeContext::height
int height
Definition: mjpegdec.h:91
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
SOS
@ SOS
Definition: mjpeg.h:72
MXpegDecodeContext::mb_width
unsigned mb_width
Definition: mxpegdec.c:43
SOF0
@ SOF0
Definition: mjpeg.h:39
AVCodecContext::err_recognition
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1420
get_bits_count
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:266
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:88
mjpegdec.h
start_code
static const uint8_t start_code[]
Definition: videotoolboxenc.c:220
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:522
MXpegDecodeContext::got_mxm_bitmask
int got_mxm_bitmask
Definition: mxpegdec.c:38
MJpegDecodeContext::first_picture
int first_picture
Definition: mjpegdec.h:69
FFCodec
Definition: codec_internal.h:127
AVFrame::flags
int flags
Frame flags, a combination of AV_FRAME_FLAGS.
Definition: frame.h:612
MXpegDecodeContext::mb_height
unsigned mb_height
Definition: mxpegdec.c:43
AV_CODEC_ID_MXPEG
@ AV_CODEC_ID_MXPEG
Definition: codec_id.h:198
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:514
MXpegDecodeContext
Definition: mxpegdec.c:33
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:30
APP15
@ APP15
Definition: mjpeg.h:94
skip_bits
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:381
ff_mjpeg_decode_dht
int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
Definition: mjpegdec.c:240
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
ff_mjpeg_decode_init
av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx)
Definition: mjpegdec.c:123
AVCodecContext::skip_frame
enum AVDiscard skip_frame
Skip decoding for selected frames.
Definition: avcodec.h:1819
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:76
MJpegDecodeContext::picture_ptr
AVFrame * picture_ptr
Definition: mjpegdec.h:109
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
COM
@ COM
Definition: mjpeg.h:111
AV_FRAME_FLAG_KEY
#define AV_FRAME_FLAG_KEY
A flag to mark frames that are keyframes.
Definition: frame.h:591
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:287
MXpegDecodeContext::picture
AVFrame * picture[2]
Definition: mxpegdec.c:35
s
#define s(width, name)
Definition: cbs_vp9.c:198
AV_GET_BUFFER_FLAG_REF
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:425
MJpegDecodeContext::interlaced
int interlaced
Definition: mjpegdec.h:70
mxpeg_decode_mxm
static int mxpeg_decode_mxm(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:90
decode.h
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
ff_mjpeg_decode_end
av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)
Definition: mjpegdec.c:2935
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
AVDISCARD_ALL
@ AVDISCARD_ALL
discard all
Definition: defs.h:219
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
ff_mjpeg_decode_dqt
int ff_mjpeg_decode_dqt(MJpegDecodeContext *s)
Definition: mjpegdec.c:197
MJpegDecodeContext::gb
GetBitContext gb
Definition: mjpegdec.h:57
MXpegDecodeContext::mxm_bitmask
uint8_t * mxm_bitmask
Definition: mxpegdec.c:39
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:279
MJpegDecodeContext
Definition: mjpegdec.h:54
ff_mxpeg_decoder
const FFCodec ff_mxpeg_decoder
Definition: mxpegdec.c:345
MJpegDecodeContext::width
int width
Definition: mjpegdec.h:91
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:442
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1568
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:365
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:523
av_frame_ref
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:312
codec_internal.h
ff_mjpeg_decode_sos
int ff_mjpeg_decode_sos(MJpegDecodeContext *s, const uint8_t *mb_bitmask, int mb_bitmask_size, const AVFrame *reference)
Definition: mjpegdec.c:1667
MXpegDecodeContext::picture_index
int picture_index
Definition: mxpegdec.c:36
DQT
@ DQT
Definition: mjpeg.h:73
mxpeg_decode_app
static int mxpeg_decode_app(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:78
MXpegDecodeContext::got_sof_data
int got_sof_data
Definition: mxpegdec.c:37
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
EOI
@ EOI
Definition: mjpeg.h:71
mxpeg_decode_init
static av_cold int mxpeg_decode_init(AVCodecContext *avctx)
Definition: mxpegdec.c:65
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:534
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:254
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
len
int len
Definition: vorbis_enc_data.h:426
DHT
@ DHT
Definition: mjpeg.h:56
mxpeg_decode_end
static av_cold int mxpeg_decode_end(AVCodecContext *avctx)
Definition: mxpegdec.c:46
MXpegDecodeContext::jpg
MJpegDecodeContext jpg
Definition: mxpegdec.c:34
mxpeg_check_dimensions
static int mxpeg_check_dimensions(MXpegDecodeContext *s, MJpegDecodeContext *jpg, AVFrame *reference_ptr)
Definition: mxpegdec.c:158
ret
ret
Definition: filter_design.txt:187
mxpeg_decode_frame
static int mxpeg_decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt)
Definition: mxpegdec.c:183
ff_mjpeg_find_marker
int ff_mjpeg_find_marker(MJpegDecodeContext *s, const uint8_t **buf_ptr, const uint8_t *buf_end, const uint8_t **unescaped_buf_ptr, int *unescaped_buf_size)
Definition: mjpegdec.c:2236
MXpegDecodeContext::bitmask_size
unsigned bitmask_size
Definition: mxpegdec.c:40
AVCodecContext
main external API structure.
Definition: avcodec.h:445
ff_mjpeg_decode_sof
int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
Definition: mjpegdec.c:301
APP0
@ APP0
Definition: mjpeg.h:79
MJpegDecodeContext::got_picture
int got_picture
we found a SOF and picture is valid, too.
Definition: mjpegdec.h:110
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:280
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
SOI
@ SOI
Definition: mjpeg.h:70
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
MAX_COMPONENTS
#define MAX_COMPONENTS
Definition: mjpegdec.h:45
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:385
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
mxpeg_decode_com
static int mxpeg_decode_com(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:143
MXpegDecodeContext::has_complete_frame
int has_complete_frame
Definition: mxpegdec.c:41
AV_RB16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:98
MXpegDecodeContext::completion_bitmask
uint8_t * completion_bitmask
Definition: mxpegdec.c:42