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 "internal.h"
29 #include "mjpeg.h"
30 #include "mjpegdec.h"
31 
32 typedef struct MXpegDecodeContext {
34  AVFrame *picture[2]; /* pictures array */
35  int picture_index; /* index of current picture */
36  int got_sof_data; /* true if SOF data successfully parsed */
37  int got_mxm_bitmask; /* true if MXM bitmask available */
38  uint8_t *mxm_bitmask; /* bitmask buffer */
39  unsigned bitmask_size; /* size of bitmask */
40  int has_complete_frame; /* true if has complete frame */
41  uint8_t *completion_bitmask; /* completion bitmask of macroblocks */
42  unsigned mb_width, mb_height; /* size of picture in MB's from MXM header */
44 
46 {
47  MXpegDecodeContext *s = avctx->priv_data;
48  MJpegDecodeContext *jpg = &s->jpg;
49  int i;
50 
51  jpg->picture_ptr = NULL;
52  ff_mjpeg_decode_end(avctx);
53 
54  for (i = 0; i < 2; ++i)
55  av_frame_free(&s->picture[i]);
56 
57  s->bitmask_size = 0;
58  av_freep(&s->mxm_bitmask);
59  av_freep(&s->completion_bitmask);
60 
61  return 0;
62 }
63 
65 {
66  MXpegDecodeContext *s = avctx->priv_data;
67 
68  s->picture[0] = av_frame_alloc();
69  s->picture[1] = av_frame_alloc();
70  if (!s->picture[0] || !s->picture[1])
71  return AVERROR(ENOMEM);
72 
73  s->jpg.picture_ptr = s->picture[0];
74  return ff_mjpeg_decode_init(avctx);
75 }
76 
78  const uint8_t *buf_ptr, int buf_size)
79 {
80  int len;
81  if (buf_size < 2)
82  return 0;
83  len = AV_RB16(buf_ptr);
84  skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
85 
86  return 0;
87 }
88 
90  const uint8_t *buf_ptr, int buf_size)
91 {
92  unsigned bitmask_size, mb_count;
93  int i;
94 
95  s->mb_width = AV_RL16(buf_ptr+4);
96  s->mb_height = AV_RL16(buf_ptr+6);
97  mb_count = s->mb_width * s->mb_height;
98 
99  bitmask_size = (mb_count + 7) >> 3;
100  if (bitmask_size > buf_size - 12) {
101  av_log(s->jpg.avctx, AV_LOG_ERROR,
102  "MXM bitmask is not complete\n");
103  return AVERROR(EINVAL);
104  }
105 
106  if (s->bitmask_size != bitmask_size) {
107  s->bitmask_size = 0;
108  av_freep(&s->mxm_bitmask);
109  s->mxm_bitmask = av_malloc(bitmask_size);
110  if (!s->mxm_bitmask) {
111  av_log(s->jpg.avctx, AV_LOG_ERROR,
112  "MXM bitmask memory allocation error\n");
113  return AVERROR(ENOMEM);
114  }
115 
116  av_freep(&s->completion_bitmask);
117  s->completion_bitmask = av_mallocz(bitmask_size);
118  if (!s->completion_bitmask) {
119  av_log(s->jpg.avctx, AV_LOG_ERROR,
120  "Completion bitmask memory allocation error\n");
121  return AVERROR(ENOMEM);
122  }
123 
124  s->bitmask_size = bitmask_size;
125  }
126 
127  memcpy(s->mxm_bitmask, buf_ptr + 12, bitmask_size);
128  s->got_mxm_bitmask = 1;
129 
130  if (!s->has_complete_frame) {
131  uint8_t completion_check = 0xFF;
132  for (i = 0; i < bitmask_size; ++i) {
133  s->completion_bitmask[i] |= s->mxm_bitmask[i];
134  completion_check &= s->completion_bitmask[i];
135  }
136  s->has_complete_frame = !(completion_check ^ 0xFF);
137  }
138 
139  return 0;
140 }
141 
143  const uint8_t *buf_ptr, int buf_size)
144 {
145  int len, ret = 0;
146  if (buf_size < 2)
147  return 0;
148  len = AV_RB16(buf_ptr);
149  if (len > 14 && len <= buf_size && !strncmp(buf_ptr + 2, "MXM", 3)) {
150  ret = mxpeg_decode_mxm(s, buf_ptr + 2, len - 2);
151  }
152  skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
153 
154  return ret;
155 }
156 
158  AVFrame *reference_ptr)
159 {
160  if ((jpg->width + 0x0F)>>4 != s->mb_width ||
161  (jpg->height + 0x0F)>>4 != s->mb_height) {
162  av_log(jpg->avctx, AV_LOG_ERROR,
163  "Picture dimensions stored in SOF and MXM mismatch\n");
164  return AVERROR(EINVAL);
165  }
166 
167  if (reference_ptr->data[0]) {
168  int i;
169  for (i = 0; i < MAX_COMPONENTS; ++i) {
170  if ( (!reference_ptr->data[i] ^ !jpg->picture_ptr->data[i]) ||
171  reference_ptr->linesize[i] != jpg->picture_ptr->linesize[i]) {
172  av_log(jpg->avctx, AV_LOG_ERROR,
173  "Dimensions of current and reference picture mismatch\n");
174  return AVERROR(EINVAL);
175  }
176  }
177  }
178 
179  return 0;
180 }
181 
183  void *data, int *got_frame,
184  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;
289  jpg->picture_ptr->key_frame = 0;
290  jpg->got_picture = 1;
291  } else {
293  jpg->picture_ptr->key_frame = 1;
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(data, 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  .name = "mxpeg",
347  .long_name = NULL_IF_CONFIG_SMALL("Mobotix MxPEG video"),
348  .type = AVMEDIA_TYPE_VIDEO,
349  .id = AV_CODEC_ID_MXPEG,
350  .priv_data_size = sizeof(MXpegDecodeContext),
352  .close = mxpeg_decode_end,
354  .capabilities = AV_CODEC_CAP_DR1,
355  .max_lowres = 3,
357 };
AVCodec
AVCodec.
Definition: codec.h:202
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
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:42
mjpeg.h
MJpegDecodeContext::avctx
AVCodecContext * avctx
Definition: mjpegdec.h:56
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
MJpegDecodeContext::height
int height
Definition: mjpegdec.h:93
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:42
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:1324
get_bits_count
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:220
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:112
mjpegdec.h
start_code
static const uint8_t start_code[]
Definition: videotoolboxenc.c:191
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:310
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:373
MXpegDecodeContext::got_mxm_bitmask
int got_mxm_bitmask
Definition: mxpegdec.c:37
data
const char data[16]
Definition: mxf.c:143
MJpegDecodeContext::first_picture
int first_picture
Definition: mjpegdec.h:71
MXpegDecodeContext::mb_height
unsigned mb_height
Definition: mxpegdec.c:42
AV_CODEC_ID_MXPEG
@ AV_CODEC_ID_MXPEG
Definition: codec_id.h:196
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:660
MXpegDecodeContext
Definition: mxpegdec.c:32
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:329
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
APP15
@ APP15
Definition: mjpeg.h:94
skip_bits
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:468
ff_mjpeg_decode_dht
int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
Definition: mjpegdec.c:237
ff_mjpeg_decode_init
av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx)
Definition: mjpegdec.c:118
AVCodecContext::skip_frame
enum AVDiscard skip_frame
Skip decoding for selected frames.
Definition: avcodec.h:1673
AVFrame::key_frame
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:400
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:99
MJpegDecodeContext::picture_ptr
AVFrame * picture_ptr
Definition: mjpegdec.h:111
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
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
MXpegDecodeContext::picture
AVFrame * picture[2]
Definition: mxpegdec.c:34
s
#define s(width, name)
Definition: cbs_vp9.c:257
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:361
MJpegDecodeContext::interlaced
int interlaced
Definition: mjpegdec.h:72
mxpeg_decode_mxm
static int mxpeg_decode_mxm(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:89
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:2946
AVDISCARD_ALL
@ AVDISCARD_ALL
discard all
Definition: defs.h:54
mxpeg_decode_frame
static int mxpeg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mxpegdec.c:182
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:194
MJpegDecodeContext::gb
GetBitContext gb
Definition: mjpegdec.h:57
MXpegDecodeContext::mxm_bitmask
uint8_t * mxm_bitmask
Definition: mxpegdec.c:38
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
MJpegDecodeContext
Definition: mjpegdec.h:54
AV_EF_EXPLODE
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:1335
MJpegDecodeContext::width
int width
Definition: mjpegdec.h:93
ff_mxpeg_decoder
const AVCodec ff_mxpeg_decoder
Definition: mxpegdec.c:345
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:405
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1651
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:374
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
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:327
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:1633
MXpegDecodeContext::picture_index
int picture_index
Definition: mxpegdec.c:35
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:77
MXpegDecodeContext::got_sof_data
int got_sof_data
Definition: mxpegdec.c:36
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
EOI
@ EOI
Definition: mjpeg.h:71
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:50
mxpeg_decode_init
static av_cold int mxpeg_decode_init(AVCodecContext *avctx)
Definition: mxpegdec.c:64
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:437
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:263
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
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:45
MXpegDecodeContext::jpg
MJpegDecodeContext jpg
Definition: mxpegdec.c:33
mxpeg_check_dimensions
static int mxpeg_check_dimensions(MXpegDecodeContext *s, MJpegDecodeContext *jpg, AVFrame *reference_ptr)
Definition: mxpegdec.c:157
ret
ret
Definition: filter_design.txt:187
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:2203
MXpegDecodeContext::bitmask_size
unsigned bitmask_size
Definition: mxpegdec.c:39
AVCodecContext
main external API structure.
Definition: avcodec.h:383
ff_mjpeg_decode_sof
int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
Definition: mjpegdec.c:298
APP0
@ APP0
Definition: mjpeg.h:79
MJpegDecodeContext::got_picture
int got_picture
we found a SOF and picture is valid, too.
Definition: mjpegdec.h:112
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
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:350
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:410
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
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:353
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
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:142
MXpegDecodeContext::has_complete_frame
int has_complete_frame
Definition: mxpegdec.c:40
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:41