FFmpeg  4.4
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  buf_ptr = buf;
197  buf_end = buf + buf_size;
198  jpg->got_picture = 0;
199  s->got_mxm_bitmask = 0;
200  s->got_sof_data = !!s->got_sof_data;
201  while (buf_ptr < buf_end) {
202  start_code = ff_mjpeg_find_marker(jpg, &buf_ptr, buf_end,
203  &unescaped_buf_ptr, &unescaped_buf_size);
204  if (start_code < 0)
205  goto the_end;
206  {
207  init_get_bits(&jpg->gb, unescaped_buf_ptr, unescaped_buf_size*8);
208 
209  if (start_code >= APP0 && start_code <= APP15) {
210  mxpeg_decode_app(s, unescaped_buf_ptr, unescaped_buf_size);
211  }
212 
213  switch (start_code) {
214  case SOI:
215  if (jpg->got_picture) //emulating EOI
216  goto the_end;
217  break;
218  case EOI:
219  goto the_end;
220  case DQT:
221  ret = ff_mjpeg_decode_dqt(jpg);
222  if (ret < 0) {
223  av_log(avctx, AV_LOG_ERROR,
224  "quantization table decode error\n");
225  return ret;
226  }
227  break;
228  case DHT:
229  ret = ff_mjpeg_decode_dht(jpg);
230  if (ret < 0) {
231  av_log(avctx, AV_LOG_ERROR,
232  "huffman table decode error\n");
233  return ret;
234  }
235  break;
236  case COM:
237  ret = mxpeg_decode_com(s, unescaped_buf_ptr,
238  unescaped_buf_size);
239  if (ret < 0)
240  return ret;
241  break;
242  case SOF0:
243  if (s->got_sof_data > 1) {
244  av_log(avctx, AV_LOG_ERROR,
245  "Multiple SOF in a frame\n");
246  return AVERROR_INVALIDDATA;
247  }
248  ret = ff_mjpeg_decode_sof(jpg);
249  if (ret < 0) {
250  av_log(avctx, AV_LOG_ERROR,
251  "SOF data decode error\n");
252  s->got_sof_data = 0;
253  return ret;
254  }
255  if (jpg->interlaced) {
256  av_log(avctx, AV_LOG_ERROR,
257  "Interlaced mode not supported in MxPEG\n");
258  s->got_sof_data = 0;
259  return AVERROR(EINVAL);
260  }
261  s->got_sof_data ++;
262  break;
263  case SOS:
264  if (!s->got_sof_data) {
265  av_log(avctx, AV_LOG_WARNING,
266  "Can not process SOS without SOF data, skipping\n");
267  break;
268  }
269  if (!jpg->got_picture) {
270  if (jpg->first_picture) {
271  av_log(avctx, AV_LOG_WARNING,
272  "First picture has no SOF, skipping\n");
273  break;
274  }
275  if (!s->got_mxm_bitmask){
276  av_log(avctx, AV_LOG_WARNING,
277  "Non-key frame has no MXM, skipping\n");
278  break;
279  }
280  /* use stored SOF data to allocate current picture */
282  if ((ret = ff_get_buffer(avctx, jpg->picture_ptr,
284  return ret;
286  jpg->picture_ptr->key_frame = 0;
287  jpg->got_picture = 1;
288  } else {
290  jpg->picture_ptr->key_frame = 1;
291  }
292 
293  if (s->got_mxm_bitmask) {
294  AVFrame *reference_ptr = s->picture[s->picture_index ^ 1];
295  if (mxpeg_check_dimensions(s, jpg, reference_ptr) < 0)
296  break;
297 
298  /* allocate dummy reference picture if needed */
299  if (!reference_ptr->data[0] &&
300  (ret = ff_get_buffer(avctx, reference_ptr,
302  return ret;
303 
304  ret = ff_mjpeg_decode_sos(jpg, s->mxm_bitmask, s->bitmask_size, reference_ptr);
305  if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
306  return ret;
307  } else {
308  ret = ff_mjpeg_decode_sos(jpg, NULL, 0, NULL);
309  if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
310  return ret;
311  }
312 
313  break;
314  }
315 
316  buf_ptr += (get_bits_count(&jpg->gb)+7) >> 3;
317  }
318 
319  }
320 
321 the_end:
322  if (jpg->got_picture) {
323  int ret = av_frame_ref(data, jpg->picture_ptr);
324  if (ret < 0)
325  return ret;
326  *got_frame = 1;
327 
328  s->picture_index ^= 1;
329  jpg->picture_ptr = s->picture[s->picture_index];
330 
331  if (!s->has_complete_frame) {
332  if (!s->got_mxm_bitmask)
333  s->has_complete_frame = 1;
334  else
335  *got_frame = 0;
336  }
337  }
338 
339  return buf_ptr - buf;
340 }
341 
343  .name = "mxpeg",
344  .long_name = NULL_IF_CONFIG_SMALL("Mobotix MxPEG video"),
345  .type = AVMEDIA_TYPE_VIDEO,
346  .id = AV_CODEC_ID_MXPEG,
347  .priv_data_size = sizeof(MXpegDecodeContext),
349  .close = mxpeg_decode_end,
351  .capabilities = AV_CODEC_CAP_DR1,
352  .max_lowres = 3,
354 };
#define av_cold
Definition: attributes.h:88
uint8_t
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:1656
#define AV_RL16
Definition: intreadwrite.h:42
#define AV_RB16
Definition: intreadwrite.h:53
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
#define s(width, name)
Definition: cbs_vp9.c:257
#define FFMIN(a, b)
Definition: common.h:105
#define NULL
Definition: coverity.c:32
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1893
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:467
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:219
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:659
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:514
@ AV_CODEC_ID_MXPEG
Definition: codec_id.h:195
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
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
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
int i
Definition: input.c:407
#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
#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
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
MJPEG encoder and decoder.
@ APP15
Definition: mjpeg.h:94
@ DQT
Definition: mjpeg.h:73
@ DHT
Definition: mjpeg.h:56
@ SOS
Definition: mjpeg.h:72
@ APP0
Definition: mjpeg.h:79
@ SOI
Definition: mjpeg.h:70
@ EOI
Definition: mjpeg.h:71
@ COM
Definition: mjpeg.h:111
@ SOF0
Definition: mjpeg.h:39
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:2194
av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx)
Definition: mjpegdec.c:117
int ff_mjpeg_decode_dqt(MJpegDecodeContext *s)
Definition: mjpegdec.c:195
av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)
Definition: mjpegdec.c:2881
int ff_mjpeg_decode_sos(MJpegDecodeContext *s, const uint8_t *mb_bitmask, int mb_bitmask_size, const AVFrame *reference)
Definition: mjpegdec.c:1624
int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
Definition: mjpegdec.c:297
int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
Definition: mjpegdec.c:236
MJPEG decoder.
#define MAX_COMPONENTS
Definition: mjpegdec.h:45
const char data[16]
Definition: mxf.c:142
AVCodec ff_mxpeg_decoder
Definition: mxpegdec.c:342
static av_cold int mxpeg_decode_init(AVCodecContext *avctx)
Definition: mxpegdec.c:64
static int mxpeg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mxpegdec.c:182
static int mxpeg_check_dimensions(MXpegDecodeContext *s, MJpegDecodeContext *jpg, AVFrame *reference_ptr)
Definition: mxpegdec.c:157
static int mxpeg_decode_com(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:142
static int mxpeg_decode_mxm(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:89
static int mxpeg_decode_app(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)
Definition: mxpegdec.c:77
static av_cold int mxpeg_decode_end(AVCodecContext *avctx)
Definition: mxpegdec.c:45
main external API structure.
Definition: avcodec.h:536
void * priv_data
Definition: avcodec.h:563
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1645
AVCodec.
Definition: codec.h:197
const char * name
Name of the codec implementation.
Definition: codec.h:204
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:332
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:396
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:349
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:401
This structure stores compressed data.
Definition: packet.h:346
int size
Definition: packet.h:370
uint8_t * data
Definition: packet.h:369
AVFrame * picture_ptr
Definition: mjpegdec.h:109
GetBitContext gb
Definition: mjpegdec.h:55
int got_picture
we found a SOF and picture is valid, too.
Definition: mjpegdec.h:110
AVCodecContext * avctx
Definition: mjpegdec.h:54
MJpegDecodeContext jpg
Definition: mxpegdec.c:33
uint8_t * mxm_bitmask
Definition: mxpegdec.c:38
AVFrame * picture[2]
Definition: mxpegdec.c:34
unsigned bitmask_size
Definition: mxpegdec.c:39
int has_complete_frame
Definition: mxpegdec.c:40
unsigned mb_width
Definition: mxpegdec.c:42
uint8_t * completion_bitmask
Definition: mxpegdec.c:41
unsigned mb_height
Definition: mxpegdec.c:42
#define av_freep(p)
#define av_malloc(s)
#define av_log(a,...)
static const uint8_t start_code[]
int len