FFmpeg
moflex.c
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1 /*
2  * MOFLEX demuxer
3  * Copyright (c) 2015-2016 Florian Nouwt
4  * Copyright (c) 2017 Adib Surani
5  * Copyright (c) 2020 Paul B Mahol
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 #include "libavcodec/bytestream.h"
25 
26 #include "avformat.h"
27 #include "internal.h"
28 
29 typedef struct BitReader {
30  unsigned last;
31  unsigned pos;
32 } BitReader;
33 
34 typedef struct MOFLEXDemuxContext {
35  unsigned size;
36  int64_t pos;
37  int64_t ts;
38  int flags;
39  int in_block;
40 
43 
44 static int pop(BitReader *br, AVIOContext *pb)
45 {
46  if (avio_feof(pb))
47  return AVERROR_EOF;
48 
49  if ((br->pos & 7) == 0)
50  br->last = (unsigned)avio_r8(pb) << 24U;
51  else
52  br->last <<= 1;
53 
54  br->pos++;
55  return !!(br->last & 0x80000000);
56 }
57 
58 static int pop_int(BitReader *br, AVIOContext *pb, int n)
59 {
60  int value = 0;
61 
62  for (int i = 0; i < n; i++) {
63  int ret = pop(br, pb);
64 
65  if (ret < 0)
66  return ret;
67  if (ret > INT_MAX - value - value)
68  return AVERROR_INVALIDDATA;
69  value = 2 * value + ret;
70  }
71 
72  return value;
73 }
74 
75 static int pop_length(BitReader *br, AVIOContext *pb)
76 {
77  int ret, n = 1;
78 
79  while ((ret = pop(br, pb)) == 0)
80  n++;
81 
82  if (ret < 0)
83  return ret;
84  return n;
85 }
86 
87 static int read_var_byte(AVFormatContext *s, unsigned *out)
88 {
89  AVIOContext *pb = s->pb;
90  unsigned value = 0, data;
91 
92  data = avio_r8(pb);
93  if (!(data & 0x80)) {
94  *out = data;
95  return 0;
96  }
97 
98  value = (data & 0x7F) << 7;
99  data = avio_r8(pb);
100  if (!(data & 0x80)) {
101  value |= data;
102  *out = value;
103  return 0;
104  }
105 
106  value = ((data & 0x7F) | value) << 7;
107  data = avio_r8(pb);
108  if (!(data & 0x80)) {
109  value |= data;
110  *out = value;
111  return 0;
112  }
113 
114  value = (((data & 0x7F) | value) << 7) | avio_r8(pb);
115  *out = value;
116 
117  return 0;
118 }
119 
120 static int moflex_probe(const AVProbeData *p)
121 {
122  GetByteContext gb;
123  int score = 0;
124 
125  bytestream2_init(&gb, p->buf, p->buf_size);
126 
127  if (bytestream2_get_be16(&gb) != 0x4C32)
128  return 0;
129  score += 10;
130 
131  bytestream2_skip(&gb, 10);
132  if (bytestream2_get_be16(&gb) == 0)
133  return 0;
134  score += 5;
135 
136  while (bytestream2_get_bytes_left(&gb) > 0) {
137  int type = bytestream2_get_byte(&gb);
138  int size = bytestream2_get_byte(&gb);
139 
140  if (type == 0) {
141  score += 5 * (size == 0);
142  break;
143  }
144  if ((type == 1 && size == 12) ||
145  (type == 2 && size == 6) ||
146  (type == 3 && size == 13) ||
147  (type == 4 && size == 2))
148  score += 20;
149  bytestream2_skip(&gb, size);
150  }
151 
152  return FFMIN(AVPROBE_SCORE_MAX, score);
153 }
154 
156 {
157  MOFLEXDemuxContext *m = s->priv_data;
158  AVIOContext *pb = s->pb;
159 
160  if (avio_rb16(pb) != 0x4C32) {
161  if (avio_feof(pb))
162  return AVERROR_EOF;
163  avio_seek(pb, -2, SEEK_CUR);
164  return 1;
165  }
166 
167  avio_skip(pb, 2);
168  m->ts = avio_rb64(pb);
169  m->size = avio_rb16(pb) + 1;
170 
171  while (!avio_feof(pb)) {
172  unsigned type, ssize, codec_id = 0;
173  unsigned codec_type, width = 0, height = 0, sample_rate = 0, channels = 0;
174  int stream_index = -1;
175  AVRational fps;
176 
177  read_var_byte(s, &type);
178  read_var_byte(s, &ssize);
179 
180  switch (type) {
181  case 0:
182  if (ssize > 0)
183  avio_skip(pb, ssize);
184  return 0;
185  case 2:
187  stream_index = avio_r8(pb);
188  codec_id = avio_r8(pb);
189  switch (codec_id) {
190  case 0: codec_id = AV_CODEC_ID_FASTAUDIO; break;
191  case 1: codec_id = AV_CODEC_ID_ADPCM_IMA_MOFLEX; break;
192  case 2: codec_id = AV_CODEC_ID_PCM_S16LE; break;
193  default:
194  av_log(s, AV_LOG_ERROR, "Unsupported audio codec: %d\n", codec_id);
195  return AVERROR_PATCHWELCOME;
196  }
197  sample_rate = avio_rb24(pb) + 1;
198  channels = avio_r8(pb) + 1;
199  break;
200  case 1:
201  case 3:
203  stream_index = avio_r8(pb);
204  codec_id = avio_r8(pb);
205  switch (codec_id) {
206  case 0: codec_id = AV_CODEC_ID_MOBICLIP; break;
207  default:
208  av_log(s, AV_LOG_ERROR, "Unsupported video codec: %d\n", codec_id);
209  return AVERROR_PATCHWELCOME;
210  }
211  fps.num = avio_rb16(pb);
212  fps.den = avio_rb16(pb);
213  width = avio_rb16(pb);
214  height = avio_rb16(pb);
215  avio_skip(pb, type == 3 ? 3 : 2);
216  break;
217  case 4:
219  stream_index = avio_r8(pb);
220  avio_skip(pb, 1);
221  break;
222  }
223 
224  if (stream_index == s->nb_streams) {
226 
227  if (!st)
228  return AVERROR(ENOMEM);
229 
231  st->codecpar->codec_id = codec_id;
232  st->codecpar->width = width;
233  st->codecpar->height = height;
235  st->codecpar->channels = channels;
236  st->priv_data = av_packet_alloc();
237  if (!st->priv_data)
238  return AVERROR(ENOMEM);
239 
240  if (sample_rate)
241  avpriv_set_pts_info(st, 63, 1, sample_rate);
242  else
243  avpriv_set_pts_info(st, 63, fps.den, fps.num);
244  }
245  }
246 
247  return 0;
248 }
249 
251 {
252  int ret;
253 
255  if (ret < 0)
256  return ret;
257 
258  s->ctx_flags |= AVFMTCTX_NOHEADER;
259  avio_seek(s->pb, 0, SEEK_SET);
260 
261  return 0;
262 }
263 
265 {
266  MOFLEXDemuxContext *m = s->priv_data;
267  AVIOContext *pb = s->pb;
268  BitReader *br = &m->br;
269  int ret;
270 
271  while (!avio_feof(pb)) {
272  if (!m->in_block) {
273  m->pos = avio_tell(pb);
274 
276  if (ret < 0)
277  return ret;
278 
279  m->flags = avio_r8(pb);
280  if (m->flags & 2)
281  avio_skip(pb, 2);
282  }
283 
284  while ((avio_tell(pb) < m->pos + m->size) && !avio_feof(pb) && avio_r8(pb)) {
285  int stream_index, bits, pkt_size, endframe;
286  AVPacket *packet;
287 
288  m->in_block = 1;
289 
290  avio_seek(pb, -1, SEEK_CUR);
291  br->pos = br->last = 0;
292 
293  bits = pop_length(br, pb);
294  if (bits < 0)
295  return bits;
296  stream_index = pop_int(br, pb, bits);
297  if (stream_index < 0)
298  return stream_index;
299  if (stream_index >= s->nb_streams)
300  return AVERROR_INVALIDDATA;
301 
302  endframe = pop(br, pb);
303  if (endframe < 0)
304  return endframe;
305  if (endframe) {
306  bits = pop_length(br, pb);
307  if (bits < 0)
308  return bits;
309  pop_int(br, pb, bits);
310  pop(br, pb);
311  bits = pop_length(br, pb);
312  if (bits < 0)
313  return bits;
314  pop_int(br, pb, bits * 2 + 26);
315  }
316 
317  pkt_size = pop_int(br, pb, 13) + 1;
318  if (pkt_size > m->size)
319  return AVERROR_INVALIDDATA;
320  packet = s->streams[stream_index]->priv_data;
321  if (!packet) {
322  avio_skip(pb, pkt_size);
323  continue;
324  }
325 
326  ret = av_append_packet(pb, packet, pkt_size);
327  if (ret < 0)
328  return ret;
329  if (endframe && packet->size > 0) {
330  av_packet_move_ref(pkt, packet);
331  pkt->pos = m->pos;
332  pkt->stream_index = stream_index;
333  if (s->streams[stream_index]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
334  pkt->duration = 1;
335  if (pkt->data[0] & 0x80)
337  } else {
339  }
340  return ret;
341  }
342  }
343 
344  m->in_block = 0;
345 
346  if (m->flags % 2 == 0) {
347  if (m->size <= 0)
348  return AVERROR_INVALIDDATA;
349  avio_seek(pb, m->pos + m->size, SEEK_SET);
350  }
351  }
352 
353  return AVERROR_EOF;
354 }
355 
356 static int moflex_read_seek(AVFormatContext *s, int stream_index,
357  int64_t pts, int flags)
358 {
359  MOFLEXDemuxContext *m = s->priv_data;
360 
361  m->in_block = 0;
362 
363  return -1;
364 }
365 
367 {
368  for (int i = 0; i < s->nb_streams; i++) {
369  av_packet_free((AVPacket **)&s->streams[i]->priv_data);
370  }
371 
372  return 0;
373 }
374 
376  .name = "moflex",
377  .long_name = NULL_IF_CONFIG_SMALL("MobiClip MOFLEX"),
378  .priv_data_size = sizeof(MOFLEXDemuxContext),
384  .extensions = "moflex",
386 };
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:313
pop_length
static int pop_length(BitReader *br, AVIOContext *pb)
Definition: moflex.c:75
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:724
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
BitReader
Definition: moflex.c:29
out
FILE * out
Definition: movenc.c:54
GetByteContext
Definition: bytestream.h:33
AVStream::priv_data
void * priv_data
Definition: avformat.h:854
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AV_CODEC_ID_MOBICLIP
@ AV_CODEC_ID_MOBICLIP
Definition: codec_id.h:303
AV_CODEC_ID_FASTAUDIO
@ AV_CODEC_ID_FASTAUDIO
Definition: codec_id.h:516
AVPacket::data
uint8_t * data
Definition: packet.h:373
moflex_probe
static int moflex_probe(const AVProbeData *p)
Definition: moflex.c:120
data
const char data[16]
Definition: mxf.c:143
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:391
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
codec_type
enum AVMediaType codec_type
Definition: rtp.c:37
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:425
sample_rate
sample_rate
Definition: ffmpeg_filter.c:156
av_packet_free
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:75
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
U
#define U(x)
Definition: vp56_arith.h:37
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:149
MOFLEXDemuxContext
Definition: moflex.c:34
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:141
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:486
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
MOFLEXDemuxContext::ts
int64_t ts
Definition: moflex.c:37
pop
static int pop(BitReader *br, AVIOContext *pb)
Definition: moflex.c:44
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
pts
static int64_t pts
Definition: transcode_aac.c:653
AVRational::num
int num
Numerator.
Definition: rational.h:59
MOFLEXDemuxContext::flags
int flags
Definition: moflex.c:38
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:626
width
#define width
s
#define s(width, name)
Definition: cbs_vp9.c:257
MOFLEXDemuxContext::br
BitReader br
Definition: moflex.c:41
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:631
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:126
bits
uint8_t bits
Definition: vp3data.h:141
channels
channels
Definition: aptx.h:33
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:369
AVMEDIA_TYPE_DATA
@ AVMEDIA_TYPE_DATA
Opaque data information usually continuous.
Definition: avutil.h:203
AVFormatContext
Format I/O context.
Definition: avformat.h:1097
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:992
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVFMTCTX_NOHEADER
#define AVFMTCTX_NOHEADER
signal that no header is present (streams are added dynamically)
Definition: avformat.h:1048
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
MOFLEXDemuxContext::size
unsigned size
Definition: moflex.c:35
avio_rb64
uint64_t avio_rb64(AVIOContext *s)
Definition: aviobuf.c:894
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
av_packet_move_ref
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:474
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
moflex_read_close
static int moflex_read_close(AVFormatContext *s)
Definition: moflex.c:366
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
avio_rb24
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:766
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
size
int size
Definition: twinvq_data.h:10344
pop_int
static int pop_int(BitReader *br, AVIOContext *pb, int n)
Definition: moflex.c:58
moflex_read_seek
static int moflex_read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags)
Definition: moflex.c:356
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:616
height
#define height
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:379
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.c:64
moflex_read_sync
static int moflex_read_sync(AVFormatContext *s)
Definition: moflex.c:155
BitReader::last
unsigned last
Definition: moflex.c:30
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
AVCodecParameters::height
int height
Definition: codec_par.h:127
read_var_byte
static int read_var_byte(AVFormatContext *s, unsigned *out)
Definition: moflex.c:87
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:845
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:758
av_append_packet
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size)
Read data and append it to the current content of the AVPacket.
Definition: utils.c:212
avformat.h
AVRational::den
int den
Denominator.
Definition: rational.h:60
moflex_read_packet
static int moflex_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: moflex.c:264
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:1146
AVPacket::stream_index
int stream_index
Definition: packet.h:375
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:333
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
moflex_read_header
static int moflex_read_header(AVFormatContext *s)
Definition: moflex.c:250
AV_CODEC_ID_ADPCM_IMA_MOFLEX
@ AV_CODEC_ID_ADPCM_IMA_MOFLEX
Definition: codec_id.h:401
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:393
bytestream.h
MOFLEXDemuxContext::in_block
int in_block
Definition: moflex.c:39
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
ff_moflex_demuxer
const AVInputFormat ff_moflex_demuxer
Definition: moflex.c:375
BitReader::pos
unsigned pos
Definition: moflex.c:31
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
MOFLEXDemuxContext::pos
int64_t pos
Definition: moflex.c:36
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:360