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);
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  mxpeg_decode_end(avctx);
72  return AVERROR(ENOMEM);
73  }
74 
75  s->jpg.picture_ptr = s->picture[0];
76  return ff_mjpeg_decode_init(avctx);
77 }
78 
80  const uint8_t *buf_ptr, int buf_size)
81 {
82  int len;
83  if (buf_size < 2)
84  return 0;
85  len = AV_RB16(buf_ptr);
86  skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
87 
88  return 0;
89 }
90 
92  const uint8_t *buf_ptr, int buf_size)
93 {
94  unsigned bitmask_size, mb_count;
95  int i;
96 
97  s->mb_width = AV_RL16(buf_ptr+4);
98  s->mb_height = AV_RL16(buf_ptr+6);
99  mb_count = s->mb_width * s->mb_height;
100 
101  bitmask_size = (mb_count + 7) >> 3;
102  if (bitmask_size > buf_size - 12) {
104  "MXM bitmask is not complete\n");
105  return AVERROR(EINVAL);
106  }
107 
108  if (s->bitmask_size != bitmask_size) {
109  s->bitmask_size = 0;
110  av_freep(&s->mxm_bitmask);
111  s->mxm_bitmask = av_malloc(bitmask_size);
112  if (!s->mxm_bitmask) {
114  "MXM bitmask memory allocation error\n");
115  return AVERROR(ENOMEM);
116  }
117 
119  s->completion_bitmask = av_mallocz(bitmask_size);
120  if (!s->completion_bitmask) {
122  "Completion bitmask memory allocation error\n");
123  return AVERROR(ENOMEM);
124  }
125 
127  }
128 
129  memcpy(s->mxm_bitmask, buf_ptr + 12, bitmask_size);
130  s->got_mxm_bitmask = 1;
131 
132  if (!s->has_complete_frame) {
133  uint8_t completion_check = 0xFF;
134  for (i = 0; i < bitmask_size; ++i) {
135  s->completion_bitmask[i] |= s->mxm_bitmask[i];
136  completion_check &= s->completion_bitmask[i];
137  }
138  s->has_complete_frame = !(completion_check ^ 0xFF);
139  }
140 
141  return 0;
142 }
143 
145  const uint8_t *buf_ptr, int buf_size)
146 {
147  int len, ret = 0;
148  if (buf_size < 2)
149  return 0;
150  len = AV_RB16(buf_ptr);
151  if (len > 14 && len <= buf_size && !strncmp(buf_ptr + 2, "MXM", 3)) {
152  ret = mxpeg_decode_mxm(s, buf_ptr + 2, len - 2);
153  }
154  skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
155 
156  return ret;
157 }
158 
160  AVFrame *reference_ptr)
161 {
162  if ((jpg->width + 0x0F)>>4 != s->mb_width ||
163  (jpg->height + 0x0F)>>4 != s->mb_height) {
164  av_log(jpg->avctx, AV_LOG_ERROR,
165  "Picture dimensions stored in SOF and MXM mismatch\n");
166  return AVERROR(EINVAL);
167  }
168 
169  if (reference_ptr->data[0]) {
170  int i;
171  for (i = 0; i < MAX_COMPONENTS; ++i) {
172  if ( (!reference_ptr->data[i] ^ !jpg->picture_ptr->data[i]) ||
173  reference_ptr->linesize[i] != jpg->picture_ptr->linesize[i]) {
174  av_log(jpg->avctx, AV_LOG_ERROR,
175  "Dimensions of current and reference picture mismatch\n");
176  return AVERROR(EINVAL);
177  }
178  }
179  }
180 
181  return 0;
182 }
183 
185  void *data, int *got_frame,
186  AVPacket *avpkt)
187 {
188  const uint8_t *buf = avpkt->data;
189  int buf_size = avpkt->size;
190  MXpegDecodeContext *s = avctx->priv_data;
191  MJpegDecodeContext *jpg = &s->jpg;
192  const uint8_t *buf_end, *buf_ptr;
193  const uint8_t *unescaped_buf_ptr;
194  int unescaped_buf_size;
195  int start_code;
196  int ret;
197 
198  buf_ptr = buf;
199  buf_end = buf + buf_size;
200  jpg->got_picture = 0;
201  s->got_mxm_bitmask = 0;
202  while (buf_ptr < buf_end) {
203  start_code = ff_mjpeg_find_marker(jpg, &buf_ptr, buf_end,
204  &unescaped_buf_ptr, &unescaped_buf_size);
205  if (start_code < 0)
206  goto the_end;
207  {
208  init_get_bits(&jpg->gb, unescaped_buf_ptr, unescaped_buf_size*8);
209 
210  if (start_code >= APP0 && start_code <= APP15) {
211  mxpeg_decode_app(s, unescaped_buf_ptr, unescaped_buf_size);
212  }
213 
214  switch (start_code) {
215  case SOI:
216  if (jpg->got_picture) //emulating EOI
217  goto the_end;
218  break;
219  case EOI:
220  goto the_end;
221  case DQT:
222  ret = ff_mjpeg_decode_dqt(jpg);
223  if (ret < 0) {
224  av_log(avctx, AV_LOG_ERROR,
225  "quantization table decode error\n");
226  return ret;
227  }
228  break;
229  case DHT:
230  ret = ff_mjpeg_decode_dht(jpg);
231  if (ret < 0) {
232  av_log(avctx, AV_LOG_ERROR,
233  "huffman table decode error\n");
234  return ret;
235  }
236  break;
237  case COM:
238  ret = mxpeg_decode_com(s, unescaped_buf_ptr,
239  unescaped_buf_size);
240  if (ret < 0)
241  return ret;
242  break;
243  case SOF0:
244  s->got_sof_data = 0;
245  ret = ff_mjpeg_decode_sof(jpg);
246  if (ret < 0) {
247  av_log(avctx, AV_LOG_ERROR,
248  "SOF data decode error\n");
249  return ret;
250  }
251  if (jpg->interlaced) {
252  av_log(avctx, AV_LOG_ERROR,
253  "Interlaced mode not supported in MxPEG\n");
254  return AVERROR(EINVAL);
255  }
256  s->got_sof_data = 1;
257  break;
258  case SOS:
259  if (!s->got_sof_data) {
260  av_log(avctx, AV_LOG_WARNING,
261  "Can not process SOS without SOF data, skipping\n");
262  break;
263  }
264  if (!jpg->got_picture) {
265  if (jpg->first_picture) {
266  av_log(avctx, AV_LOG_WARNING,
267  "First picture has no SOF, skipping\n");
268  break;
269  }
270  if (!s->got_mxm_bitmask){
271  av_log(avctx, AV_LOG_WARNING,
272  "Non-key frame has no MXM, skipping\n");
273  break;
274  }
275  /* use stored SOF data to allocate current picture */
277  if ((ret = ff_get_buffer(avctx, jpg->picture_ptr,
279  return ret;
281  jpg->picture_ptr->key_frame = 0;
282  jpg->got_picture = 1;
283  } else {
285  jpg->picture_ptr->key_frame = 1;
286  }
287 
288  if (s->got_mxm_bitmask) {
289  AVFrame *reference_ptr = s->picture[s->picture_index ^ 1];
290  if (mxpeg_check_dimensions(s, jpg, reference_ptr) < 0)
291  break;
292 
293  /* allocate dummy reference picture if needed */
294  if (!reference_ptr->data[0] &&
295  (ret = ff_get_buffer(avctx, reference_ptr,
297  return ret;
298 
299  ret = ff_mjpeg_decode_sos(jpg, s->mxm_bitmask, s->bitmask_size, reference_ptr);
300  if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
301  return ret;
302  } else {
303  ret = ff_mjpeg_decode_sos(jpg, NULL, 0, NULL);
304  if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
305  return ret;
306  }
307 
308  break;
309  }
310 
311  buf_ptr += (get_bits_count(&jpg->gb)+7) >> 3;
312  }
313 
314  }
315 
316 the_end:
317  if (jpg->got_picture) {
318  int ret = av_frame_ref(data, jpg->picture_ptr);
319  if (ret < 0)
320  return ret;
321  *got_frame = 1;
322 
323  s->picture_index ^= 1;
324  jpg->picture_ptr = s->picture[s->picture_index];
325 
326  if (!s->has_complete_frame) {
327  if (!s->got_mxm_bitmask)
328  s->has_complete_frame = 1;
329  else
330  *got_frame = 0;
331  }
332  }
333 
334  return buf_ptr - buf;
335 }
336 
338  .name = "mxpeg",
339  .long_name = NULL_IF_CONFIG_SMALL("Mobotix MxPEG video"),
340  .type = AVMEDIA_TYPE_VIDEO,
341  .id = AV_CODEC_ID_MXPEG,
342  .priv_data_size = sizeof(MXpegDecodeContext),
344  .close = mxpeg_decode_end,
346  .capabilities = AV_CODEC_CAP_DR1,
347  .max_lowres = 3,
348  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
349 };
uint8_t * completion_bitmask
Definition: mxpegdec.c:41
#define NULL
Definition: coverity.c:32
This structure describes decoded (raw) audio or video data.
Definition: frame.h:268
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
Definition: mjpeg.h:71
Definition: mjpeg.h:111
Definition: mjpeg.h:73
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
uint8_t * mxm_bitmask
Definition: mxpegdec.c:38
int ff_mjpeg_decode_dqt(MJpegDecodeContext *s)
Definition: mjpegdec.c:200
int size
Definition: avcodec.h:1478
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 int mxpeg_check_dimensions(MXpegDecodeContext *s, MJpegDecodeContext *jpg, AVFrame *reference_ptr)
Definition: mxpegdec.c:159
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:87
int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
Definition: mjpegdec.c:241
AVCodec.
Definition: avcodec.h:3477
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
MJPEG encoder and decoder.
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
static int mxpeg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mxpegdec.c:184
#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
Definition: mjpeg.h:72
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
AVCodec ff_mxpeg_decoder
Definition: mxpegdec.c:337
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
AVFrame * picture_ptr
Definition: mjpegdec.h:100
uint8_t * data
Definition: avcodec.h:1477
#define MAX_COMPONENTS
Definition: mjpegdec.h:44
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:219
#define av_log(a,...)
AVFrame * picture[2]
Definition: mxpegdec.c:34
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:260
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static int mxpeg_decode_mxm(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:91
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)
Definition: mjpegdec.c:2745
unsigned bitmask_size
Definition: mxpegdec.c:39
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3484
Definition: mjpeg.h:39
Definition: mjpeg.h:70
unsigned mb_width
Definition: mxpegdec.c:42
Definition: mjpeg.h:79
Definition: mjpeg.h:56
int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
Definition: mjpegdec.c:305
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:351
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2690
#define FFMIN(a, b)
Definition: common.h:96
#define s(width, name)
Definition: cbs_vp9.c:257
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:2701
GetBitContext gb
Definition: mjpegdec.h:49
static av_cold int mxpeg_decode_init(AVCodecContext *avctx)
Definition: mxpegdec.c:64
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:299
int has_complete_frame
Definition: mxpegdec.c:40
main external API structure.
Definition: avcodec.h:1565
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1964
void * buf
Definition: avisynth_c.h:766
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:467
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:659
MJpegDecodeContext jpg
Definition: mxpegdec.c:33
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:282
static int mxpeg_decode_com(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:144
int ff_mjpeg_decode_sos(MJpegDecodeContext *s, const uint8_t *mb_bitmask, int mb_bitmask_size, const AVFrame *reference)
Definition: mjpegdec.c:1567
av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx)
Definition: mjpegdec.c:139
Definition: mjpeg.h:94
unsigned mb_height
Definition: mxpegdec.c:42
common internal api header.
static av_cold int mxpeg_decode_end(AVCodecContext *avctx)
Definition: mxpegdec.c:45
AVCodecContext * avctx
Definition: mjpegdec.h:48
void * priv_data
Definition: avcodec.h:1592
static int mxpeg_decode_app(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:79
int got_picture
we found a SOF and picture is valid, too.
Definition: mjpegdec.h:101
int len
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:346
#define av_freep(p)
static const uint8_t start_code[]
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:2132
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
MJPEG decoder.
This structure stores compressed data.
Definition: avcodec.h:1454
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:1176
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981
Predicted.
Definition: avutil.h:275