FFmpeg  4.2.2
mlp_parse.c
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1 /*
2  * Copyright (c) 2007 Ian Caulfield
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <stdint.h>
22 
24 #include "get_bits.h"
25 #include "mlp_parse.h"
26 #include "mlp.h"
27 
28 static const uint8_t mlp_quants[16] = {
29  16, 20, 24, 0, 0, 0, 0, 0,
30  0, 0, 0, 0, 0, 0, 0, 0,
31 };
32 
33 static const uint8_t mlp_channels[32] = {
34  1, 2, 3, 4, 3, 4, 5, 3, 4, 5, 4, 5, 6, 4, 5, 4,
35  5, 6, 5, 5, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
36 };
37 
38 static const uint64_t mlp_layout[32] = {
43  AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY,
44  AV_CH_LAYOUT_2_1|AV_CH_LOW_FREQUENCY,
45  AV_CH_LAYOUT_QUAD|AV_CH_LOW_FREQUENCY,
49  AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY,
50  AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY,
54  AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY,
55  AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY,
57  AV_CH_LAYOUT_QUAD|AV_CH_LOW_FREQUENCY,
60  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
61 };
62 
63 static const uint8_t thd_chancount[13] = {
64 // LR C LFE LRs LRvh LRc LRrs Cs Ts LRsd LRw Cvh LFE2
65  2, 1, 1, 2, 2, 2, 2, 1, 1, 2, 2, 1, 1
66 };
67 
68 static const uint64_t thd_layout[13] = {
70  AV_CH_FRONT_CENTER, // C
71  AV_CH_LOW_FREQUENCY, // LFE
76  AV_CH_BACK_CENTER, // Cs
77  AV_CH_TOP_CENTER, // Ts
81  AV_CH_LOW_FREQUENCY_2, // LFE2
82 };
83 
84 static int mlp_samplerate(int in)
85 {
86  if (in == 0xF)
87  return 0;
88 
89  return (in & 8 ? 44100 : 48000) << (in & 7) ;
90 }
91 
92 static int truehd_channels(int chanmap)
93 {
94  int channels = 0, i;
95 
96  for (i = 0; i < 13; i++)
97  channels += thd_chancount[i] * ((chanmap >> i) & 1);
98 
99  return channels;
100 }
101 
102 static uint64_t truehd_layout(int chanmap)
103 {
104  int i;
105  uint64_t layout = 0;
106 
107  for (i = 0; i < 13; i++)
108  layout |= thd_layout[i] * ((chanmap >> i) & 1);
109 
110  return layout;
111 }
112 
113 static int mlp_get_major_sync_size(const uint8_t * buf, int bufsize)
114 {
115  int has_extension, extensions = 0;
116  int size = 28;
117  if (bufsize < 28)
118  return -1;
119 
120  if (AV_RB32(buf) == 0xf8726fba) {
121  has_extension = buf[25] & 1;
122  if (has_extension) {
123  extensions = buf[26] >> 4;
124  size += 2 + extensions * 2;
125  }
126  }
127  return size;
128 }
129 
130 /** Read a major sync info header - contains high level information about
131  * the stream - sample rate, channel arrangement etc. Most of this
132  * information is not actually necessary for decoding, only for playback.
133  * gb must be a freshly initialized GetBitContext with no bits read.
134  */
135 
137 {
138  int ratebits, channel_arrangement, header_size;
139  uint16_t checksum;
140 
141  av_assert1(get_bits_count(gb) == 0);
142 
143  header_size = mlp_get_major_sync_size(gb->buffer, gb->size_in_bits >> 3);
144  if (header_size < 0 || gb->size_in_bits < header_size << 3) {
145  av_log(log, AV_LOG_ERROR, "packet too short, unable to read major sync\n");
146  return -1;
147  }
148 
149  checksum = ff_mlp_checksum16(gb->buffer, header_size - 2);
150  if (checksum != AV_RL16(gb->buffer+header_size-2)) {
151  av_log(log, AV_LOG_ERROR, "major sync info header checksum error\n");
152  return AVERROR_INVALIDDATA;
153  }
154 
155  if (get_bits_long(gb, 24) != 0xf8726f) /* Sync words */
156  return AVERROR_INVALIDDATA;
157 
158  mh->stream_type = get_bits(gb, 8);
159  mh->header_size = header_size;
160 
161  if (mh->stream_type == 0xbb) {
162  mh->group1_bits = mlp_quants[get_bits(gb, 4)];
163  mh->group2_bits = mlp_quants[get_bits(gb, 4)];
164 
165  ratebits = get_bits(gb, 4);
166  mh->group1_samplerate = mlp_samplerate(ratebits);
168 
169  skip_bits(gb, 11);
170 
172  channel_arrangement = get_bits(gb, 5);
173  mh->channels_mlp = mlp_channels[channel_arrangement];
174  mh->channel_layout_mlp = mlp_layout[channel_arrangement];
175  } else if (mh->stream_type == 0xba) {
176  mh->group1_bits = 24; // TODO: Is this information actually conveyed anywhere?
177  mh->group2_bits = 0;
178 
179  ratebits = get_bits(gb, 4);
180  mh->group1_samplerate = mlp_samplerate(ratebits);
181  mh->group2_samplerate = 0;
182 
183  skip_bits(gb, 4);
184 
187 
189  channel_arrangement = get_bits(gb, 5);
190  mh->channels_thd_stream1 = truehd_channels(channel_arrangement);
191  mh->channel_layout_thd_stream1 = truehd_layout(channel_arrangement);
192 
194 
195  channel_arrangement = get_bits(gb, 13);
196  mh->channels_thd_stream2 = truehd_channels(channel_arrangement);
197  mh->channel_layout_thd_stream2 = truehd_layout(channel_arrangement);
198  } else
199  return AVERROR_INVALIDDATA;
200 
201  mh->access_unit_size = 40 << (ratebits & 7);
202  mh->access_unit_size_pow2 = 64 << (ratebits & 7);
203 
204  skip_bits_long(gb, 48);
205 
206  mh->is_vbr = get_bits1(gb);
207 
208  mh->peak_bitrate = (get_bits(gb, 15) * mh->group1_samplerate + 8) >> 4;
209 
210  mh->num_substreams = get_bits(gb, 4);
211 
212  skip_bits_long(gb, 4 + (header_size - 17) * 8);
213 
214  return 0;
215 }
int channels_thd_stream1
Channel count for substream 1 of TrueHD streams ("6-channel presentation")
Definition: mlp_parse.h:44
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int size
#define AV_CH_TOP_FRONT_RIGHT
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
#define AV_CH_LAYOUT_SURROUND
uint16_t ff_mlp_checksum16(const uint8_t *buf, unsigned int buf_size)
Definition: mlp.c:85
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:291
#define AV_CH_TOP_FRONT_LEFT
channels
Definition: aptx.c:30
int num_substreams
Number of substreams within stream.
Definition: mlp_parse.h:56
#define AV_CH_TOP_FRONT_CENTER
#define AV_CH_LOW_FREQUENCY_2
const uint8_t * buffer
Definition: get_bits.h:62
#define AV_RL16
Definition: intreadwrite.h:42
int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb)
Read a major sync info header - contains high level information about the stream - sample rate...
Definition: mlp_parse.c:136
#define AV_CH_LAYOUT_4POINT0
uint64_t channel_layout_mlp
Channel layout for MLP streams.
Definition: mlp_parse.h:46
#define AV_CH_SURROUND_DIRECT_RIGHT
#define AV_CH_LAYOUT_STEREO
int access_unit_size
Number of samples per coded frame.
Definition: mlp_parse.h:50
int peak_bitrate
Peak bitrate for VBR, actual bitrate (==peak) for CBR.
Definition: mlp_parse.h:54
static const uint8_t thd_chancount[13]
Definition: mlp_parse.c:63
#define AV_CH_WIDE_LEFT
uint8_t
int channel_modifier_thd_stream0
Channel modifier for substream 0 of TrueHD streams ("2-channel presentation")
Definition: mlp_parse.h:39
#define AV_RB32
Definition: intreadwrite.h:130
#define AV_CH_WIDE_RIGHT
#define AV_CH_LOW_FREQUENCY
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:219
bitstream reader API header.
#define AV_CH_BACK_LEFT
int channel_arrangement
Definition: mlp_parse.h:37
#define av_log(a,...)
static uint64_t truehd_layout(int chanmap)
Definition: mlp_parse.c:102
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int channel_modifier_thd_stream2
Channel modifier for substream 2 of TrueHD streams ("8-channel presentation")
Definition: mlp_parse.h:41
int channels_mlp
Channel count for MLP streams.
Definition: mlp_parse.h:43
#define AV_CH_LAYOUT_QUAD
#define AV_CH_LAYOUT_2_1
#define AV_CH_TOP_CENTER
audio channel layout utility functions
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
int size_in_bits
Definition: get_bits.h:68
int is_vbr
Stream is VBR instead of CBR.
Definition: mlp_parse.h:53
#define AV_CH_FRONT_LEFT_OF_CENTER
#define AV_CH_FRONT_CENTER
static volatile int checksum
Definition: adler32.c:30
#define AV_CH_LAYOUT_5POINT1_BACK
static int truehd_channels(int chanmap)
Definition: mlp_parse.c:92
#define AV_CH_FRONT_RIGHT_OF_CENTER
int stream_type
0xBB for MLP, 0xBA for TrueHD
Definition: mlp_parse.h:28
int access_unit_size_pow2
Next power of two above number of samples per frame.
Definition: mlp_parse.h:51
static const uint8_t mlp_quants[16]
Definition: mlp_parse.c:28
int channel_modifier_thd_stream1
Channel modifier for substream 1 of TrueHD streams ("6-channel presentation")
Definition: mlp_parse.h:40
static int mlp_get_major_sync_size(const uint8_t *buf, int bufsize)
Definition: mlp_parse.c:113
#define AV_CH_FRONT_LEFT
void * buf
Definition: avisynth_c.h:766
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31)))) #define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac) { } void ff_audio_convert_free(AudioConvert **ac) { if(! *ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);} AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map) { AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method !=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt) > 2) { ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc) { av_free(ac);return NULL;} return ac;} in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar) { ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar ? ac->channels :1;} else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);return ac;} int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in) { int use_generic=1;int len=in->nb_samples;int p;if(ac->dc) { av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (dithered)\", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:467
#define AV_CH_LAYOUT_5POINT0_BACK
static const uint8_t mlp_channels[32]
Definition: mlp_parse.c:33
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:546
int group2_bits
Bit depth of the second substream (MLP only)
Definition: mlp_parse.h:32
#define AV_CH_BACK_CENTER
#define AV_CH_SIDE_RIGHT
int channels_thd_stream2
Channel count for substream 2 of TrueHD streams ("8-channel presentation")
Definition: mlp_parse.h:45
static const uint64_t thd_layout[13]
Definition: mlp_parse.c:68
uint64_t channel_layout_thd_stream1
Channel layout for substream 1 of TrueHD streams ("6-channel presentation")
Definition: mlp_parse.h:47
uint64_t channel_layout_thd_stream2
Channel layout for substream 2 of TrueHD streams ("8-channel presentation")
Definition: mlp_parse.h:48
int header_size
Size of the major sync header, in bytes.
Definition: mlp_parse.h:29
int group1_bits
The bit depth of the first substream.
Definition: mlp_parse.h:31
uint64_t layout
#define AV_CH_SURROUND_DIRECT_LEFT
#define AV_CH_FRONT_RIGHT
#define AV_CH_SIDE_LEFT
int group1_samplerate
Sample rate of first substream.
Definition: mlp_parse.h:34
static int mlp_samplerate(int in)
Definition: mlp_parse.c:84
static const uint64_t mlp_layout[32]
Definition: mlp_parse.c:38
#define AV_CH_LAYOUT_MONO
int group2_samplerate
Sample rate of second substream (MLP only)
Definition: mlp_parse.h:35
#define mh
#define AV_CH_BACK_RIGHT