FFmpeg
lafdec.c
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1 /*
2  * Limitless Audio Format demuxer
3  * Copyright (c) 2022 Paul B Mahol
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 #include "libavutil/intreadwrite.h"
23 #include "avformat.h"
24 #include "internal.h"
25 
26 #define MAX_STREAMS 4096
27 
28 typedef struct StreamParams {
30  float horizontal;
31  float vertical;
32  int lfe;
33  int stored;
34 } StreamParams;
35 
36 typedef struct LAFContext {
37  uint8_t *data;
38  unsigned nb_stored;
39  unsigned stored_index;
40  unsigned index;
41  unsigned bpp;
42 
44 
46  uint8_t header[(MAX_STREAMS + 7) / 8];
47 } LAFContext;
48 
49 static int laf_probe(const AVProbeData *p)
50 {
51  if (memcmp(p->buf, "LIMITLESS", 9))
52  return 0;
53  if (memcmp(p->buf + 9, "HEAD", 4))
54  return 0;
55  return AVPROBE_SCORE_MAX;
56 }
57 
59 {
61  AVIOContext *pb = ctx->pb;
62  unsigned st_count, mode;
63  unsigned sample_rate;
64  int64_t duration;
65  int codec_id;
66  int quality;
67  int bpp;
68 
69  avio_skip(pb, 9);
70  if (avio_rb32(pb) != MKBETAG('H','E','A','D'))
71  return AVERROR_INVALIDDATA;
72 
73  quality = avio_r8(pb);
74  if (quality > 3)
75  return AVERROR_INVALIDDATA;
76  mode = avio_r8(pb);
77  if (mode > 1)
78  return AVERROR_INVALIDDATA;
79  st_count = avio_rl32(pb);
80  if (st_count == 0 || st_count > MAX_STREAMS)
81  return AVERROR_INVALIDDATA;
82 
83  for (int i = 0; i < st_count; i++) {
84  StreamParams *stp = &s->p[i];
85 
86  stp->vertical = av_int2float(avio_rl32(pb));
87  stp->horizontal = av_int2float(avio_rl32(pb));
88  stp->lfe = avio_r8(pb);
89  if (stp->lfe) {
91  } else if (stp->vertical == 0.f &&
92  stp->horizontal == 0.f) {
94  } else if (stp->vertical == 0.f &&
95  stp->horizontal == -30.f) {
97  } else if (stp->vertical == 0.f &&
98  stp->horizontal == 30.f) {
100  } else if (stp->vertical == 0.f &&
101  stp->horizontal == -110.f) {
103  } else if (stp->vertical == 0.f &&
104  stp->horizontal == 110.f) {
106  } else {
108  }
109  }
110 
111  sample_rate = avio_rl32(pb);
112  duration = avio_rl64(pb) / st_count;
113 
114  switch (quality) {
115  case 0:
117  bpp = 1;
118  break;
119  case 1:
121  bpp = 2;
122  break;
123  case 2:
125  bpp = 4;
126  break;
127  case 3:
129  bpp = 3;
130  break;
131  }
132 
133  s->index = 0;
134  s->stored_index = 0;
135  s->bpp = bpp;
136  if ((int64_t)bpp * st_count * (int64_t)sample_rate >= INT32_MAX)
137  return AVERROR_INVALIDDATA;
138  s->data = av_calloc(st_count * sample_rate, bpp);
139  if (!s->data)
140  return AVERROR(ENOMEM);
141 
142  for (int st = 0; st < st_count; st++) {
143  StreamParams *stp = &s->p[st];
144  AVCodecParameters *par;
146  if (!st)
147  return AVERROR(ENOMEM);
148 
149  par = st->codecpar;
150  par->codec_id = codec_id;
152  par->ch_layout.nb_channels = 1;
153  par->ch_layout = stp->layout;
154  par->sample_rate = sample_rate;
155  st->duration = duration;
156 
157  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
158  }
159 
160  s->header_len = (ctx->nb_streams + 7) / 8;
161 
162  return 0;
163 }
164 
166 {
167  AVIOContext *pb = ctx->pb;
169  AVStream *st = ctx->streams[0];
170  const int bpp = s->bpp;
171  StreamParams *stp;
172  int64_t pos;
173  int ret;
174 
175  pos = avio_tell(pb);
176 
177 again:
178  if (avio_feof(pb))
179  return AVERROR_EOF;
180 
181  if (s->index >= ctx->nb_streams) {
182  int cur_st = 0, st_count = 0, st_index = 0;
183 
184  avio_read(pb, s->header, s->header_len);
185  for (int i = 0; i < s->header_len; i++) {
186  uint8_t val = s->header[i];
187 
188  for (int j = 0; j < 8 && cur_st < ctx->nb_streams; j++, cur_st++) {
189  StreamParams *stp = &s->p[st_index];
190 
191  stp->stored = 0;
192  if (val & 1) {
193  stp->stored = 1;
194  st_count++;
195  }
196  val >>= 1;
197  st_index++;
198  }
199  }
200 
201  s->index = s->stored_index = 0;
202  s->nb_stored = st_count;
203  if (!st_count)
204  return AVERROR_INVALIDDATA;
205  ret = avio_read(pb, s->data, st_count * st->codecpar->sample_rate * bpp);
206  if (ret < 0)
207  return ret;
208  }
209 
210  st = ctx->streams[s->index];
211  stp = &s->p[s->index];
212  while (!stp->stored) {
213  s->index++;
214  if (s->index >= ctx->nb_streams)
215  goto again;
216  stp = &s->p[s->index];
217  }
218  st = ctx->streams[s->index];
219 
220  ret = av_new_packet(pkt, st->codecpar->sample_rate * bpp);
221  if (ret < 0)
222  return ret;
223 
224  switch (bpp) {
225  case 1:
226  for (int n = 0; n < st->codecpar->sample_rate; n++)
227  pkt->data[n] = s->data[n * s->nb_stored + s->stored_index];
228  break;
229  case 2:
230  for (int n = 0; n < st->codecpar->sample_rate; n++)
231  AV_WN16(pkt->data + n * 2, AV_RN16(s->data + n * s->nb_stored * 2 + s->stored_index * 2));
232  break;
233  case 3:
234  for (int n = 0; n < st->codecpar->sample_rate; n++)
235  AV_WL24(pkt->data + n * 3, AV_RL24(s->data + n * s->nb_stored * 3 + s->stored_index * 3));
236  break;
237  case 4:
238  for (int n = 0; n < st->codecpar->sample_rate; n++)
239  AV_WN32(pkt->data + n * 4, AV_RN32(s->data + n * s->nb_stored * 4 + s->stored_index * 4));
240  break;
241  }
242 
243  pkt->stream_index = s->index;
244  pkt->pos = pos;
245  s->index++;
246  s->stored_index++;
247 
248  return 0;
249 }
250 
251 static int laf_read_seek(AVFormatContext *ctx, int stream_index,
252  int64_t timestamp, int flags)
253 {
255 
256  s->stored_index = s->index = s->nb_stored = 0;
257 
258  return -1;
259 }
260 
262  .name = "laf",
263  .long_name = NULL_IF_CONFIG_SMALL("LAF (Limitless Audio Format)"),
264  .priv_data_size = sizeof(LAFContext),
269  .extensions = "laf",
271 };
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:326
StreamParams::stored
int stored
Definition: lafdec.c:33
StreamParams::horizontal
float horizontal
Definition: lafdec.c:30
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
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:54
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AV_RN16
#define AV_RN16(p)
Definition: intreadwrite.h:360
laf_read_header
static int laf_read_header(AVFormatContext *ctx)
Definition: lafdec.c:58
laf_read_seek
static int laf_read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: lafdec.c:251
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1284
AVPacket::data
uint8_t * data
Definition: packet.h:374
StreamParams::lfe
int lfe
Definition: lafdec.c:32
LAFContext::header
uint8_t header[(MAX_STREAMS+7)/8]
Definition: lafdec.c:46
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
sample_rate
sample_rate
Definition: ffmpeg_filter.c:156
quality
trying all byte sequences megabyte in length and selecting the best looking sequence will yield cases to try But a word about quality
Definition: rate_distortion.txt:12
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
LAFContext
Definition: lafdec.c:36
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
av_int2float
static av_always_inline float av_int2float(uint32_t i)
Reinterpret a 32-bit integer as a float.
Definition: intfloat.h:40
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
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
val
static double val(void *priv, double ch)
Definition: aeval.c:77
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:998
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:792
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:656
AV_CH_LOW_FREQUENCY
#define AV_CH_LOW_FREQUENCY
Definition: channel_layout.h:167
duration
int64_t duration
Definition: movenc.c:64
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
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
ctx
AVFormatContext * ctx
Definition: movenc.c:48
LAFContext::index
unsigned index
Definition: lafdec.c:40
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:388
LAFContext::data
uint8_t * data
Definition: lafdec.c:37
ff_laf_demuxer
const AVInputFormat ff_laf_demuxer
Definition: lafdec.c:261
StreamParams
Definition: lafdec.c:28
LAFContext::p
StreamParams p[MAX_STREAMS]
Definition: lafdec.c:43
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
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
MAX_STREAMS
#define MAX_STREAMS
Definition: lafdec.c:26
AV_WL24
#define AV_WL24(p, d)
Definition: intreadwrite.h:464
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1258
AV_RN32
#define AV_RN32(p)
Definition: intreadwrite.h:364
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
LAFContext::bpp
unsigned bpp
Definition: lafdec.c:41
AV_CH_FRONT_CENTER
#define AV_CH_FRONT_CENTER
Definition: channel_layout.h:166
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
AVFormatContext::nb_streams
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1272
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:761
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
AV_CODEC_ID_PCM_S24LE
@ AV_CODEC_ID_PCM_S24LE
Definition: codec_id.h:338
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
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:301
AV_WN32
#define AV_WN32(p, v)
Definition: intreadwrite.h:376
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
MKBETAG
#define MKBETAG(a, b, c, d)
Definition: macros.h:56
AV_RL24
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_RL24
Definition: bytestream.h:93
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:634
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
StreamParams::vertical
float vertical
Definition: lafdec.c:31
AV_CH_FRONT_LEFT
#define AV_CH_FRONT_LEFT
Definition: channel_layout.h:164
AV_CH_SIDE_RIGHT
#define AV_CH_SIDE_RIGHT
Definition: channel_layout.h:174
av_calloc
void * av_calloc(size_t nmemb, size_t size)
Definition: mem.c:272
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
LAFContext::stored_index
unsigned stored_index
Definition: lafdec.c:39
pos
unsigned int pos
Definition: spdifenc.c:412
avformat.h
StreamParams::layout
AVChannelLayout layout
Definition: lafdec.c:29
laf_read_packet
static int laf_read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: lafdec.c:165
again
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 again
Definition: filter_design.txt:25
mode
mode
Definition: ebur128.h:83
LAFContext::header_len
int header_len
Definition: lafdec.c:45
laf_probe
static int laf_probe(const AVProbeData *p)
Definition: lafdec.c:49
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:643
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
AV_CH_FRONT_RIGHT
#define AV_CH_FRONT_RIGHT
Definition: channel_layout.h:165
AV_CODEC_ID_PCM_U8
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:331
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:368
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
avio_rl64
uint64_t avio_rl64(AVIOContext *s)
Definition: aviobuf.c:769
AV_CHANNEL_LAYOUT_MASK
#define AV_CHANNEL_LAYOUT_MASK(nb, m)
Definition: channel_layout.h:361
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AV_CODEC_ID_PCM_F32LE
@ AV_CODEC_ID_PCM_F32LE
Definition: codec_id.h:347
LAFContext::nb_stored
unsigned nb_stored
Definition: lafdec.c:38
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1244
AV_CH_SIDE_LEFT
#define AV_CH_SIDE_LEFT
Definition: channel_layout.h:173
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:377
AV_WN16
#define AV_WN16(p, v)
Definition: intreadwrite.h:372