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 tb = av_make_q(0, 1);
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  tb = av_make_q(1, sample_rate);
199  channels = avio_r8(pb) + 1;
200  break;
201  case 1:
202  case 3:
204  stream_index = avio_r8(pb);
205  codec_id = avio_r8(pb);
206  switch (codec_id) {
207  case 0: codec_id = AV_CODEC_ID_MOBICLIP; break;
208  default:
209  av_log(s, AV_LOG_ERROR, "Unsupported video codec: %d\n", codec_id);
210  return AVERROR_PATCHWELCOME;
211  }
212  tb.den = avio_rb16(pb);
213  tb.num = avio_rb16(pb);
214  width = avio_rb16(pb);
215  height = avio_rb16(pb);
216  avio_skip(pb, type == 3 ? 3 : 2);
217  break;
218  case 4:
220  stream_index = avio_r8(pb);
221  avio_skip(pb, 1);
222  break;
223  }
224 
225  if (stream_index == s->nb_streams) {
227 
228  if (!st)
229  return AVERROR(ENOMEM);
230 
232  st->codecpar->codec_id = codec_id;
233  st->codecpar->width = width;
234  st->codecpar->height = height;
237  st->priv_data = av_packet_alloc();
238  if (!st->priv_data)
239  return AVERROR(ENOMEM);
240 
241  if (tb.num)
242  avpriv_set_pts_info(st, 63, tb.num, tb.den);
243  }
244  }
245 
246  return 0;
247 }
248 
250 {
251  int ret;
252 
254  if (ret < 0)
255  return ret;
256 
257  s->ctx_flags |= AVFMTCTX_NOHEADER;
258  avio_seek(s->pb, 0, SEEK_SET);
259 
260  return 0;
261 }
262 
264 {
265  MOFLEXDemuxContext *m = s->priv_data;
266  AVIOContext *pb = s->pb;
267  BitReader *br = &m->br;
268  int ret;
269 
270  while (!avio_feof(pb)) {
271  if (!m->in_block) {
272  m->pos = avio_tell(pb);
273 
275  if (ret < 0)
276  return ret;
277 
278  m->flags = avio_r8(pb);
279  if (m->flags & 2)
280  avio_skip(pb, 2);
281  }
282 
283  while ((avio_tell(pb) < m->pos + m->size) && !avio_feof(pb) && avio_r8(pb)) {
284  int stream_index, bits, pkt_size, endframe;
285  AVPacket *packet;
286 
287  m->in_block = 1;
288 
289  avio_seek(pb, -1, SEEK_CUR);
290  br->pos = br->last = 0;
291 
292  bits = pop_length(br, pb);
293  if (bits < 0)
294  return bits;
295  stream_index = pop_int(br, pb, bits);
296  if (stream_index < 0)
297  return stream_index;
298  if (stream_index >= s->nb_streams)
299  return AVERROR_INVALIDDATA;
300 
301  endframe = pop(br, pb);
302  if (endframe < 0)
303  return endframe;
304  if (endframe) {
305  bits = pop_length(br, pb);
306  if (bits < 0)
307  return bits;
308  pop_int(br, pb, bits);
309  pop(br, pb);
310  bits = pop_length(br, pb);
311  if (bits < 0)
312  return bits;
313  pop_int(br, pb, bits * 2 + 26);
314  }
315 
316  pkt_size = pop_int(br, pb, 13) + 1;
317  if (pkt_size > m->size)
318  return AVERROR_INVALIDDATA;
319  packet = s->streams[stream_index]->priv_data;
320  if (!packet) {
321  avio_skip(pb, pkt_size);
322  continue;
323  }
324 
325  ret = av_append_packet(pb, packet, pkt_size);
326  if (ret < 0)
327  return ret;
328  if (endframe && packet->size > 0) {
329  av_packet_move_ref(pkt, packet);
330  pkt->pos = m->pos;
331  pkt->stream_index = stream_index;
332  if (s->streams[stream_index]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
333  pkt->duration = 1;
334  if (pkt->data[0] & 0x80)
336  } else {
338  }
339  return ret;
340  }
341  }
342 
343  m->in_block = 0;
344 
345  if (m->flags % 2 == 0) {
346  if (m->size <= 0)
347  return AVERROR_INVALIDDATA;
348  avio_seek(pb, m->pos + m->size, SEEK_SET);
349  }
350  }
351 
352  return AVERROR_EOF;
353 }
354 
355 static int moflex_read_seek(AVFormatContext *s, int stream_index,
356  int64_t pts, int flags)
357 {
358  MOFLEXDemuxContext *m = s->priv_data;
359 
360  m->in_block = 0;
361 
362  return -1;
363 }
364 
366 {
367  for (int i = 0; i < s->nb_streams; i++) {
368  av_packet_free((AVPacket **)&s->streams[i]->priv_data);
369  }
370 
371  return 0;
372 }
373 
375  .name = "moflex",
376  .long_name = NULL_IF_CONFIG_SMALL("MobiClip MOFLEX"),
377  .priv_data_size = sizeof(MOFLEXDemuxContext),
383  .extensions = "moflex",
385  .flags_internal = FF_FMT_INIT_CLEANUP,
386 };
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:326
pop_length
static int pop_length(BitReader *br, AVIOContext *pb)
Definition: moflex.c:75
FF_FMT_INIT_CLEANUP
#define FF_FMT_INIT_CLEANUP
For an AVInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
Definition: internal.h:47
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: options.c:237
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
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:964
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AV_CODEC_ID_MOBICLIP
@ AV_CODEC_ID_MOBICLIP
Definition: codec_id.h:307
AV_CODEC_ID_FASTAUDIO
@ AV_CODEC_ID_FASTAUDIO
Definition: codec_id.h:529
AVPacket::data
uint8_t * data
Definition: packet.h:374
moflex_probe
static int moflex_probe(const AVProbeData *p)
Definition: moflex.c:120
data
const char data[16]
Definition: mxf.c:146
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:392
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:456
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
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:429
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:73
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
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:763
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
MOFLEXDemuxContext
Definition: moflex.c:34
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:510
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:482
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:654
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:656
width
#define width
s
#define s(width, name)
Definition: cbs_vp9.c:256
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:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
bits
uint8_t bits
Definition: vp3data.h:128
channels
channels
Definition: aptx.h:31
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:388
AVMEDIA_TYPE_DATA
@ AVMEDIA_TYPE_DATA
Opaque data information usually continuous.
Definition: avutil.h:203
AVFormatContext
Format I/O context.
Definition: avformat.h:1216
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:540
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:1167
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:939
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
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:479
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
moflex_read_close
static int moflex_read_close(AVFormatContext *s)
Definition: moflex.c:365
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:166
avio_rb24
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:785
AVPacket::size
int size
Definition: packet.h:375
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:115
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
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:355
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:634
height
#define height
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.c:62
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:269
AVCodecParameters::height
int height
Definition: codec_par.h:129
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
tb
#define tb
Definition: regdef.h:68
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:948
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:262
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:777
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:118
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:263
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:349
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
moflex_read_header
static int moflex_read_header(AVFormatContext *s)
Definition: moflex.c:249
AV_CODEC_ID_ADPCM_IMA_MOFLEX
@ AV_CODEC_ID_ADPCM_IMA_MOFLEX
Definition: codec_id.h:414
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
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:374
BitReader::pos
unsigned pos
Definition: moflex.c:31
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:36
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:377