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 "demux.h"
28 #include "internal.h"
29 
30 typedef struct BitReader {
31  unsigned last;
32  unsigned pos;
33 } BitReader;
34 
35 typedef struct MOFLEXDemuxContext {
36  unsigned size;
37  int64_t pos;
38  int64_t ts;
39  int flags;
40  int in_block;
41 
44 
45 static int pop(BitReader *br, AVIOContext *pb)
46 {
47  if (avio_feof(pb))
48  return AVERROR_EOF;
49 
50  if ((br->pos & 7) == 0)
51  br->last = (unsigned)avio_r8(pb) << 24U;
52  else
53  br->last <<= 1;
54 
55  br->pos++;
56  return !!(br->last & 0x80000000);
57 }
58 
59 static int pop_int(BitReader *br, AVIOContext *pb, int n)
60 {
61  int value = 0;
62 
63  for (int i = 0; i < n; i++) {
64  int ret = pop(br, pb);
65 
66  if (ret < 0)
67  return ret;
68  if (ret > INT_MAX - value - value)
69  return AVERROR_INVALIDDATA;
70  value = 2 * value + ret;
71  }
72 
73  return value;
74 }
75 
76 static int pop_length(BitReader *br, AVIOContext *pb)
77 {
78  int ret, n = 1;
79 
80  while ((ret = pop(br, pb)) == 0)
81  n++;
82 
83  if (ret < 0)
84  return ret;
85  return n;
86 }
87 
88 static int read_var_byte(AVFormatContext *s, unsigned *out)
89 {
90  AVIOContext *pb = s->pb;
91  unsigned value = 0, data;
92 
93  data = avio_r8(pb);
94  if (!(data & 0x80)) {
95  *out = data;
96  return 0;
97  }
98 
99  value = (data & 0x7F) << 7;
100  data = avio_r8(pb);
101  if (!(data & 0x80)) {
102  value |= data;
103  *out = value;
104  return 0;
105  }
106 
107  value = ((data & 0x7F) | value) << 7;
108  data = avio_r8(pb);
109  if (!(data & 0x80)) {
110  value |= data;
111  *out = value;
112  return 0;
113  }
114 
115  value = (((data & 0x7F) | value) << 7) | avio_r8(pb);
116  *out = value;
117 
118  return 0;
119 }
120 
121 static int moflex_probe(const AVProbeData *p)
122 {
123  GetByteContext gb;
124  int score = 0;
125 
126  bytestream2_init(&gb, p->buf, p->buf_size);
127 
128  if (bytestream2_get_be16(&gb) != 0x4C32)
129  return 0;
130  score += 10;
131 
132  bytestream2_skip(&gb, 10);
133  if (bytestream2_get_be16(&gb) == 0)
134  return 0;
135  score += 5;
136 
137  while (bytestream2_get_bytes_left(&gb) > 0) {
138  int type = bytestream2_get_byte(&gb);
139  int size = bytestream2_get_byte(&gb);
140 
141  if (type == 0) {
142  score += 5 * (size == 0);
143  break;
144  }
145  if ((type == 1 && size == 12) ||
146  (type == 2 && size == 6) ||
147  (type == 3 && size == 13) ||
148  (type == 4 && size == 2))
149  score += 20;
150  bytestream2_skip(&gb, size);
151  }
152 
153  return FFMIN(AVPROBE_SCORE_MAX, score);
154 }
155 
157 {
158  MOFLEXDemuxContext *m = s->priv_data;
159  AVIOContext *pb = s->pb;
160 
161  if (avio_rb16(pb) != 0x4C32) {
162  if (avio_feof(pb))
163  return AVERROR_EOF;
164  avio_seek(pb, -2, SEEK_CUR);
165  return 1;
166  }
167 
168  avio_skip(pb, 2);
169  m->ts = avio_rb64(pb);
170  m->size = avio_rb16(pb) + 1;
171 
172  while (!avio_feof(pb)) {
173  unsigned type, ssize, codec_id = 0;
174  unsigned codec_type, width = 0, height = 0, sample_rate = 0, channels = 0;
175  int stream_index = -1;
176  AVRational tb = av_make_q(0, 1);
177 
178  read_var_byte(s, &type);
179  read_var_byte(s, &ssize);
180 
181  switch (type) {
182  case 0:
183  if (ssize > 0)
184  avio_skip(pb, ssize);
185  return 0;
186  case 2:
188  stream_index = avio_r8(pb);
189  codec_id = avio_r8(pb);
190  switch (codec_id) {
191  case 0: codec_id = AV_CODEC_ID_FASTAUDIO; break;
192  case 1: codec_id = AV_CODEC_ID_ADPCM_IMA_MOFLEX; break;
193  case 2: codec_id = AV_CODEC_ID_PCM_S16LE; break;
194  default:
195  av_log(s, AV_LOG_ERROR, "Unsupported audio codec: %d\n", codec_id);
196  return AVERROR_PATCHWELCOME;
197  }
198  sample_rate = avio_rb24(pb) + 1;
199  tb = av_make_q(1, sample_rate);
200  channels = avio_r8(pb) + 1;
201  break;
202  case 1:
203  case 3:
205  stream_index = avio_r8(pb);
206  codec_id = avio_r8(pb);
207  switch (codec_id) {
208  case 0: codec_id = AV_CODEC_ID_MOBICLIP; break;
209  default:
210  av_log(s, AV_LOG_ERROR, "Unsupported video codec: %d\n", codec_id);
211  return AVERROR_PATCHWELCOME;
212  }
213  tb.den = avio_rb16(pb);
214  tb.num = avio_rb16(pb);
215  width = avio_rb16(pb);
216  height = avio_rb16(pb);
217  avio_skip(pb, type == 3 ? 3 : 2);
218  break;
219  case 4:
221  stream_index = avio_r8(pb);
222  avio_skip(pb, 1);
223  break;
224  }
225 
226  if (stream_index == s->nb_streams) {
228 
229  if (!st)
230  return AVERROR(ENOMEM);
231 
233  st->codecpar->codec_id = codec_id;
234  st->codecpar->width = width;
235  st->codecpar->height = height;
238  st->priv_data = av_packet_alloc();
239  if (!st->priv_data)
240  return AVERROR(ENOMEM);
241 
242  if (tb.num)
243  avpriv_set_pts_info(st, 63, tb.num, tb.den);
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  .p.name = "moflex",
377  .p.long_name = NULL_IF_CONFIG_SMALL("MobiClip MOFLEX"),
378  .p.extensions = "moflex",
379  .p.flags = AVFMT_GENERIC_INDEX,
380  .priv_data_size = sizeof(MOFLEXDemuxContext),
386  .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP,
387 };
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:328
pop_length
static int pop_length(BitReader *br, AVIOContext *pb)
Definition: moflex.c:76
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
BitReader
Definition: moflex.c:30
out
FILE * out
Definition: movenc.c:55
GetByteContext
Definition: bytestream.h:33
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVStream::priv_data
void * priv_data
Definition: avformat.h:768
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AV_CODEC_ID_MOBICLIP
@ AV_CODEC_ID_MOBICLIP
Definition: codec_id.h:304
AV_CODEC_ID_FASTAUDIO
@ AV_CODEC_ID_FASTAUDIO
Definition: codec_id.h:534
AVPacket::data
uint8_t * data
Definition: packet.h:524
moflex_probe
static int moflex_probe(const AVProbeData *p)
Definition: moflex.c:121
data
const char data[16]
Definition: mxf.c:148
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:542
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:454
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:313
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:579
sample_rate
sample_rate
Definition: ffmpeg_filter.c:424
av_packet_free
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: packet.c:74
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
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: avformat.c:853
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
MOFLEXDemuxContext
Definition: moflex.c:35
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:143
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
MOFLEXDemuxContext::ts
int64_t ts
Definition: moflex.c:38
pop
static int pop(BitReader *br, AVIOContext *pb)
Definition: moflex.c:45
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:644
MOFLEXDemuxContext::flags
int flags
Definition: moflex.c:39
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
width
#define width
s
#define s(width, name)
Definition: cbs_vp9.c:198
MOFLEXDemuxContext::br
BitReader br
Definition: moflex.c:42
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:134
bits
uint8_t bits
Definition: vp3data.h:128
channels
channels
Definition: aptx.h:31
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:392
AVMEDIA_TYPE_DATA
@ AVMEDIA_TYPE_DATA
Opaque data information usually continuous.
Definition: avutil.h:203
FF_INFMT_FLAG_INIT_CLEANUP
#define FF_INFMT_FLAG_INIT_CLEANUP
For an FFInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
Definition: demux.h:35
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
AVFMTCTX_NOHEADER
#define AVFMTCTX_NOHEADER
signal that no header is present (streams are added dynamically)
Definition: avformat.h:1206
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
MOFLEXDemuxContext::size
unsigned size
Definition: moflex.c:36
avio_rb64
uint64_t avio_rb64(AVIOContext *s)
Definition: aviobuf.c:908
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
av_packet_move_ref
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: packet.c:484
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
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:160
avio_rb24
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:754
AVPacket::size
int size
Definition: packet.h:525
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:94
size
int size
Definition: twinvq_data.h:10344
av_make_q
static AVRational av_make_q(int num, int den)
Create an AVRational.
Definition: rational.h:71
ff_moflex_demuxer
const FFInputFormat ff_moflex_demuxer
Definition: moflex.c:375
pop_int
static int pop_int(BitReader *br, AVIOContext *pb, int n)
Definition: moflex.c:59
moflex_read_seek
static int moflex_read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags)
Definition: moflex.c:356
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:603
height
#define height
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:530
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: packet.c:63
moflex_read_sync
static int moflex_read_sync(AVFormatContext *s)
Definition: moflex.c:156
BitReader::last
unsigned last
Definition: moflex.c:31
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
AVCodecParameters::height
int height
Definition: codec_par.h:135
read_var_byte
static int read_var_byte(AVFormatContext *s, unsigned *out)
Definition: moflex.c:88
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
tb
#define tb
Definition: regdef.h:68
demux.h
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:231
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:746
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:107
avformat.h
U
#define U(x)
Definition: vpx_arith.h:37
moflex_read_packet
static int moflex_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: moflex.c:264
AVPacket::stream_index
int stream_index
Definition: packet.h:526
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:318
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
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:416
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:501
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:544
FFInputFormat
Definition: demux.h:37
bytestream.h
MOFLEXDemuxContext::in_block
int in_block
Definition: moflex.c:40
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:474
BitReader::pos
unsigned pos
Definition: moflex.c:32
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
MOFLEXDemuxContext::pos
int64_t pos
Definition: moflex.c:37
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:346