-
Notifications
You must be signed in to change notification settings - Fork 3
/
dr_flac.h
12269 lines (10224 loc) · 502 KB
/
dr_flac.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
FLAC audio decoder. Choice of public domain or MIT-0. See license statements at the end of this file.
dr_flac - v0.12.31 - 2021-08-16
David Reid - [email protected]
GitHub: https://github.com/mackron/dr_libs
*/
/*
RELEASE NOTES - v0.12.0
=======================
Version 0.12.0 has breaking API changes including changes to the existing API and the removal of deprecated APIs.
Improved Client-Defined Memory Allocation
-----------------------------------------
The main change with this release is the addition of a more flexible way of implementing custom memory allocation routines. The
existing system of DRFLAC_MALLOC, DRFLAC_REALLOC and DRFLAC_FREE are still in place and will be used by default when no custom
allocation callbacks are specified.
To use the new system, you pass in a pointer to a drflac_allocation_callbacks object to drflac_open() and family, like this:
void* my_malloc(size_t sz, void* pUserData)
{
return malloc(sz);
}
void* my_realloc(void* p, size_t sz, void* pUserData)
{
return realloc(p, sz);
}
void my_free(void* p, void* pUserData)
{
free(p);
}
...
drflac_allocation_callbacks allocationCallbacks;
allocationCallbacks.pUserData = &myData;
allocationCallbacks.onMalloc = my_malloc;
allocationCallbacks.onRealloc = my_realloc;
allocationCallbacks.onFree = my_free;
drflac* pFlac = drflac_open_file("my_file.flac", &allocationCallbacks);
The advantage of this new system is that it allows you to specify user data which will be passed in to the allocation routines.
Passing in null for the allocation callbacks object will cause dr_flac to use defaults which is the same as DRFLAC_MALLOC,
DRFLAC_REALLOC and DRFLAC_FREE and the equivalent of how it worked in previous versions.
Every API that opens a drflac object now takes this extra parameter. These include the following:
drflac_open()
drflac_open_relaxed()
drflac_open_with_metadata()
drflac_open_with_metadata_relaxed()
drflac_open_file()
drflac_open_file_with_metadata()
drflac_open_memory()
drflac_open_memory_with_metadata()
drflac_open_and_read_pcm_frames_s32()
drflac_open_and_read_pcm_frames_s16()
drflac_open_and_read_pcm_frames_f32()
drflac_open_file_and_read_pcm_frames_s32()
drflac_open_file_and_read_pcm_frames_s16()
drflac_open_file_and_read_pcm_frames_f32()
drflac_open_memory_and_read_pcm_frames_s32()
drflac_open_memory_and_read_pcm_frames_s16()
drflac_open_memory_and_read_pcm_frames_f32()
Optimizations
-------------
Seeking performance has been greatly improved. A new binary search based seeking algorithm has been introduced which significantly
improves performance over the brute force method which was used when no seek table was present. Seek table based seeking also takes
advantage of the new binary search seeking system to further improve performance there as well. Note that this depends on CRC which
means it will be disabled when DR_FLAC_NO_CRC is used.
The SSE4.1 pipeline has been cleaned up and optimized. You should see some improvements with decoding speed of 24-bit files in
particular. 16-bit streams should also see some improvement.
drflac_read_pcm_frames_s16() has been optimized. Previously this sat on top of drflac_read_pcm_frames_s32() and performed it's s32
to s16 conversion in a second pass. This is now all done in a single pass. This includes SSE2 and ARM NEON optimized paths.
A minor optimization has been implemented for drflac_read_pcm_frames_s32(). This will now use an SSE2 optimized pipeline for stereo
channel reconstruction which is the last part of the decoding process.
The ARM build has seen a few improvements. The CLZ (count leading zeroes) and REV (byte swap) instructions are now used when
compiling with GCC and Clang which is achieved using inline assembly. The CLZ instruction requires ARM architecture version 5 at
compile time and the REV instruction requires ARM architecture version 6.
An ARM NEON optimized pipeline has been implemented. To enable this you'll need to add -mfpu=neon to the command line when compiling.
Removed APIs
------------
The following APIs were deprecated in version 0.11.0 and have been completely removed in version 0.12.0:
drflac_read_s32() -> drflac_read_pcm_frames_s32()
drflac_read_s16() -> drflac_read_pcm_frames_s16()
drflac_read_f32() -> drflac_read_pcm_frames_f32()
drflac_seek_to_sample() -> drflac_seek_to_pcm_frame()
drflac_open_and_decode_s32() -> drflac_open_and_read_pcm_frames_s32()
drflac_open_and_decode_s16() -> drflac_open_and_read_pcm_frames_s16()
drflac_open_and_decode_f32() -> drflac_open_and_read_pcm_frames_f32()
drflac_open_and_decode_file_s32() -> drflac_open_file_and_read_pcm_frames_s32()
drflac_open_and_decode_file_s16() -> drflac_open_file_and_read_pcm_frames_s16()
drflac_open_and_decode_file_f32() -> drflac_open_file_and_read_pcm_frames_f32()
drflac_open_and_decode_memory_s32() -> drflac_open_memory_and_read_pcm_frames_s32()
drflac_open_and_decode_memory_s16() -> drflac_open_memory_and_read_pcm_frames_s16()
drflac_open_and_decode_memory_f32() -> drflac_open_memroy_and_read_pcm_frames_f32()
Prior versions of dr_flac operated on a per-sample basis whereas now it operates on PCM frames. The removed APIs all relate
to the old per-sample APIs. You now need to use the "pcm_frame" versions.
*/
/*
Introduction
============
dr_flac is a single file library. To use it, do something like the following in one .c file.
```c
#define DR_FLAC_IMPLEMENTATION
#include "dr_flac.h"
```
You can then #include this file in other parts of the program as you would with any other header file. To decode audio data, do something like the following:
```c
drflac* pFlac = drflac_open_file("MySong.flac", NULL);
if (pFlac == NULL) {
// Failed to open FLAC file
}
drflac_int32* pSamples = malloc(pFlac->totalPCMFrameCount * pFlac->channels * sizeof(drflac_int32));
drflac_uint64 numberOfInterleavedSamplesActuallyRead = drflac_read_pcm_frames_s32(pFlac, pFlac->totalPCMFrameCount, pSamples);
```
The drflac object represents the decoder. It is a transparent type so all the information you need, such as the number of channels and the bits per sample,
should be directly accessible - just make sure you don't change their values. Samples are always output as interleaved signed 32-bit PCM. In the example above
a native FLAC stream was opened, however dr_flac has seamless support for Ogg encapsulated FLAC streams as well.
You do not need to decode the entire stream in one go - you just specify how many samples you'd like at any given time and the decoder will give you as many
samples as it can, up to the amount requested. Later on when you need the next batch of samples, just call it again. Example:
```c
while (drflac_read_pcm_frames_s32(pFlac, chunkSizeInPCMFrames, pChunkSamples) > 0) {
do_something();
}
```
You can seek to a specific PCM frame with `drflac_seek_to_pcm_frame()`.
If you just want to quickly decode an entire FLAC file in one go you can do something like this:
```c
unsigned int channels;
unsigned int sampleRate;
drflac_uint64 totalPCMFrameCount;
drflac_int32* pSampleData = drflac_open_file_and_read_pcm_frames_s32("MySong.flac", &channels, &sampleRate, &totalPCMFrameCount, NULL);
if (pSampleData == NULL) {
// Failed to open and decode FLAC file.
}
...
drflac_free(pSampleData, NULL);
```
You can read samples as signed 16-bit integer and 32-bit floating-point PCM with the *_s16() and *_f32() family of APIs respectively, but note that these
should be considered lossy.
If you need access to metadata (album art, etc.), use `drflac_open_with_metadata()`, `drflac_open_file_with_metdata()` or `drflac_open_memory_with_metadata()`.
The rationale for keeping these APIs separate is that they're slightly slower than the normal versions and also just a little bit harder to use. dr_flac
reports metadata to the application through the use of a callback, and every metadata block is reported before `drflac_open_with_metdata()` returns.
The main opening APIs (`drflac_open()`, etc.) will fail if the header is not present. The presents a problem in certain scenarios such as broadcast style
streams or internet radio where the header may not be present because the user has started playback mid-stream. To handle this, use the relaxed APIs:
`drflac_open_relaxed()`
`drflac_open_with_metadata_relaxed()`
It is not recommended to use these APIs for file based streams because a missing header would usually indicate a corrupt or perverse file. In addition, these
APIs can take a long time to initialize because they may need to spend a lot of time finding the first frame.
Build Options
=============
#define these options before including this file.
#define DR_FLAC_NO_STDIO
Disable `drflac_open_file()` and family.
#define DR_FLAC_NO_OGG
Disables support for Ogg/FLAC streams.
#define DR_FLAC_BUFFER_SIZE <number>
Defines the size of the internal buffer to store data from onRead(). This buffer is used to reduce the number of calls back to the client for more data.
Larger values means more memory, but better performance. My tests show diminishing returns after about 4KB (which is the default). Consider reducing this if
you have a very efficient implementation of onRead(), or increase it if it's very inefficient. Must be a multiple of 8.
#define DR_FLAC_NO_CRC
Disables CRC checks. This will offer a performance boost when CRC is unnecessary. This will disable binary search seeking. When seeking, the seek table will
be used if available. Otherwise the seek will be performed using brute force.
#define DR_FLAC_NO_SIMD
Disables SIMD optimizations (SSE on x86/x64 architectures, NEON on ARM architectures). Use this if you are having compatibility issues with your compiler.
Notes
=====
- dr_flac does not support changing the sample rate nor channel count mid stream.
- dr_flac is not thread-safe, but its APIs can be called from any thread so long as you do your own synchronization.
- When using Ogg encapsulation, a corrupted metadata block will result in `drflac_open_with_metadata()` and `drflac_open()` returning inconsistent samples due
to differences in corrupted stream recorvery logic between the two APIs.
*/
#ifndef dr_flac_h
#define dr_flac_h
#ifdef __cplusplus
extern "C" {
#endif
#define DRFLAC_STRINGIFY(x) #x
#define DRFLAC_XSTRINGIFY(x) DRFLAC_STRINGIFY(x)
#define DRFLAC_VERSION_MAJOR 0
#define DRFLAC_VERSION_MINOR 12
#define DRFLAC_VERSION_REVISION 31
#define DRFLAC_VERSION_STRING DRFLAC_XSTRINGIFY(DRFLAC_VERSION_MAJOR) "." DRFLAC_XSTRINGIFY(DRFLAC_VERSION_MINOR) "." DRFLAC_XSTRINGIFY(DRFLAC_VERSION_REVISION)
#include <stddef.h> /* For size_t. */
/* Sized types. */
typedef signed char drflac_int8;
typedef unsigned char drflac_uint8;
typedef signed short drflac_int16;
typedef unsigned short drflac_uint16;
typedef signed int drflac_int32;
typedef unsigned int drflac_uint32;
#if defined(_MSC_VER)
typedef signed __int64 drflac_int64;
typedef unsigned __int64 drflac_uint64;
#else
#if defined(__clang__) || (defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)))
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wlong-long"
#if defined(__clang__)
#pragma GCC diagnostic ignored "-Wc++11-long-long"
#endif
#endif
typedef signed long long drflac_int64;
typedef unsigned long long drflac_uint64;
#if defined(__clang__) || (defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)))
#pragma GCC diagnostic pop
#endif
#endif
#if defined(__LP64__) || defined(_WIN64) || (defined(__x86_64__) && !defined(__ILP32__)) || defined(_M_X64) || defined(__ia64) || defined (_M_IA64) || defined(__aarch64__) || defined(_M_ARM64) || defined(__powerpc64__)
typedef drflac_uint64 drflac_uintptr;
#else
typedef drflac_uint32 drflac_uintptr;
#endif
typedef drflac_uint8 drflac_bool8;
typedef drflac_uint32 drflac_bool32;
#define DRFLAC_TRUE 1
#define DRFLAC_FALSE 0
#if !defined(DRFLAC_API)
#if defined(DRFLAC_DLL)
#if defined(_WIN32)
#define DRFLAC_DLL_IMPORT __declspec(dllimport)
#define DRFLAC_DLL_EXPORT __declspec(dllexport)
#define DRFLAC_DLL_PRIVATE static
#else
#if defined(__GNUC__) && __GNUC__ >= 4
#define DRFLAC_DLL_IMPORT __attribute__((visibility("default")))
#define DRFLAC_DLL_EXPORT __attribute__((visibility("default")))
#define DRFLAC_DLL_PRIVATE __attribute__((visibility("hidden")))
#else
#define DRFLAC_DLL_IMPORT
#define DRFLAC_DLL_EXPORT
#define DRFLAC_DLL_PRIVATE static
#endif
#endif
#if defined(DR_FLAC_IMPLEMENTATION) || defined(DRFLAC_IMPLEMENTATION)
#define DRFLAC_API DRFLAC_DLL_EXPORT
#else
#define DRFLAC_API DRFLAC_DLL_IMPORT
#endif
#define DRFLAC_PRIVATE DRFLAC_DLL_PRIVATE
#else
#define DRFLAC_API extern
#define DRFLAC_PRIVATE static
#endif
#endif
#if defined(_MSC_VER) && _MSC_VER >= 1700 /* Visual Studio 2012 */
#define DRFLAC_DEPRECATED __declspec(deprecated)
#elif (defined(__GNUC__) && __GNUC__ >= 4) /* GCC 4 */
#define DRFLAC_DEPRECATED __attribute__((deprecated))
#elif defined(__has_feature) /* Clang */
#if __has_feature(attribute_deprecated)
#define DRFLAC_DEPRECATED __attribute__((deprecated))
#else
#define DRFLAC_DEPRECATED
#endif
#else
#define DRFLAC_DEPRECATED
#endif
DRFLAC_API void drflac_version(drflac_uint32* pMajor, drflac_uint32* pMinor, drflac_uint32* pRevision);
DRFLAC_API const char* drflac_version_string(void);
/*
As data is read from the client it is placed into an internal buffer for fast access. This controls the size of that buffer. Larger values means more speed,
but also more memory. In my testing there is diminishing returns after about 4KB, but you can fiddle with this to suit your own needs. Must be a multiple of 8.
*/
#ifndef DR_FLAC_BUFFER_SIZE
#define DR_FLAC_BUFFER_SIZE 4096
#endif
/* Check if we can enable 64-bit optimizations. */
#if defined(_WIN64) || defined(_LP64) || defined(__LP64__)
#define DRFLAC_64BIT
#endif
#ifdef DRFLAC_64BIT
typedef drflac_uint64 drflac_cache_t;
#else
typedef drflac_uint32 drflac_cache_t;
#endif
/* The various metadata block types. */
#define DRFLAC_METADATA_BLOCK_TYPE_STREAMINFO 0
#define DRFLAC_METADATA_BLOCK_TYPE_PADDING 1
#define DRFLAC_METADATA_BLOCK_TYPE_APPLICATION 2
#define DRFLAC_METADATA_BLOCK_TYPE_SEEKTABLE 3
#define DRFLAC_METADATA_BLOCK_TYPE_VORBIS_COMMENT 4
#define DRFLAC_METADATA_BLOCK_TYPE_CUESHEET 5
#define DRFLAC_METADATA_BLOCK_TYPE_PICTURE 6
#define DRFLAC_METADATA_BLOCK_TYPE_INVALID 127
/* The various picture types specified in the PICTURE block. */
#define DRFLAC_PICTURE_TYPE_OTHER 0
#define DRFLAC_PICTURE_TYPE_FILE_ICON 1
#define DRFLAC_PICTURE_TYPE_OTHER_FILE_ICON 2
#define DRFLAC_PICTURE_TYPE_COVER_FRONT 3
#define DRFLAC_PICTURE_TYPE_COVER_BACK 4
#define DRFLAC_PICTURE_TYPE_LEAFLET_PAGE 5
#define DRFLAC_PICTURE_TYPE_MEDIA 6
#define DRFLAC_PICTURE_TYPE_LEAD_ARTIST 7
#define DRFLAC_PICTURE_TYPE_ARTIST 8
#define DRFLAC_PICTURE_TYPE_CONDUCTOR 9
#define DRFLAC_PICTURE_TYPE_BAND 10
#define DRFLAC_PICTURE_TYPE_COMPOSER 11
#define DRFLAC_PICTURE_TYPE_LYRICIST 12
#define DRFLAC_PICTURE_TYPE_RECORDING_LOCATION 13
#define DRFLAC_PICTURE_TYPE_DURING_RECORDING 14
#define DRFLAC_PICTURE_TYPE_DURING_PERFORMANCE 15
#define DRFLAC_PICTURE_TYPE_SCREEN_CAPTURE 16
#define DRFLAC_PICTURE_TYPE_BRIGHT_COLORED_FISH 17
#define DRFLAC_PICTURE_TYPE_ILLUSTRATION 18
#define DRFLAC_PICTURE_TYPE_BAND_LOGOTYPE 19
#define DRFLAC_PICTURE_TYPE_PUBLISHER_LOGOTYPE 20
typedef enum
{
drflac_container_native,
drflac_container_ogg,
drflac_container_unknown
} drflac_container;
typedef enum
{
drflac_seek_origin_start,
drflac_seek_origin_current
} drflac_seek_origin;
/* Packing is important on this structure because we map this directly to the raw data within the SEEKTABLE metadata block. */
#pragma pack(2)
typedef struct
{
drflac_uint64 firstPCMFrame;
drflac_uint64 flacFrameOffset; /* The offset from the first byte of the header of the first frame. */
drflac_uint16 pcmFrameCount;
} drflac_seekpoint;
#pragma pack()
typedef struct
{
drflac_uint16 minBlockSizeInPCMFrames;
drflac_uint16 maxBlockSizeInPCMFrames;
drflac_uint32 minFrameSizeInPCMFrames;
drflac_uint32 maxFrameSizeInPCMFrames;
drflac_uint32 sampleRate;
drflac_uint8 channels;
drflac_uint8 bitsPerSample;
drflac_uint64 totalPCMFrameCount;
drflac_uint8 md5[16];
} drflac_streaminfo;
typedef struct
{
/*
The metadata type. Use this to know how to interpret the data below. Will be set to one of the
DRFLAC_METADATA_BLOCK_TYPE_* tokens.
*/
drflac_uint32 type;
/*
A pointer to the raw data. This points to a temporary buffer so don't hold on to it. It's best to
not modify the contents of this buffer. Use the structures below for more meaningful and structured
information about the metadata. It's possible for this to be null.
*/
const void* pRawData;
/* The size in bytes of the block and the buffer pointed to by pRawData if it's non-NULL. */
drflac_uint32 rawDataSize;
union
{
drflac_streaminfo streaminfo;
struct
{
int unused;
} padding;
struct
{
drflac_uint32 id;
const void* pData;
drflac_uint32 dataSize;
} application;
struct
{
drflac_uint32 seekpointCount;
const drflac_seekpoint* pSeekpoints;
} seektable;
struct
{
drflac_uint32 vendorLength;
const char* vendor;
drflac_uint32 commentCount;
const void* pComments;
} vorbis_comment;
struct
{
char catalog[128];
drflac_uint64 leadInSampleCount;
drflac_bool32 isCD;
drflac_uint8 trackCount;
const void* pTrackData;
} cuesheet;
struct
{
drflac_uint32 type;
drflac_uint32 mimeLength;
const char* mime;
drflac_uint32 descriptionLength;
const char* description;
drflac_uint32 width;
drflac_uint32 height;
drflac_uint32 colorDepth;
drflac_uint32 indexColorCount;
drflac_uint32 pictureDataSize;
const drflac_uint8* pPictureData;
} picture;
} data;
} drflac_metadata;
/*
Callback for when data needs to be read from the client.
Parameters
----------
pUserData (in)
The user data that was passed to drflac_open() and family.
pBufferOut (out)
The output buffer.
bytesToRead (in)
The number of bytes to read.
Return Value
------------
The number of bytes actually read.
Remarks
-------
A return value of less than bytesToRead indicates the end of the stream. Do _not_ return from this callback until either the entire bytesToRead is filled or
you have reached the end of the stream.
*/
typedef size_t (* drflac_read_proc)(void* pUserData, void* pBufferOut, size_t bytesToRead);
/*
Callback for when data needs to be seeked.
Parameters
----------
pUserData (in)
The user data that was passed to drflac_open() and family.
offset (in)
The number of bytes to move, relative to the origin. Will never be negative.
origin (in)
The origin of the seek - the current position or the start of the stream.
Return Value
------------
Whether or not the seek was successful.
Remarks
-------
The offset will never be negative. Whether or not it is relative to the beginning or current position is determined by the "origin" parameter which will be
either drflac_seek_origin_start or drflac_seek_origin_current.
When seeking to a PCM frame using drflac_seek_to_pcm_frame(), dr_flac may call this with an offset beyond the end of the FLAC stream. This needs to be detected
and handled by returning DRFLAC_FALSE.
*/
typedef drflac_bool32 (* drflac_seek_proc)(void* pUserData, int offset, drflac_seek_origin origin);
/*
Callback for when a metadata block is read.
Parameters
----------
pUserData (in)
The user data that was passed to drflac_open() and family.
pMetadata (in)
A pointer to a structure containing the data of the metadata block.
Remarks
-------
Use pMetadata->type to determine which metadata block is being handled and how to read the data. This
will be set to one of the DRFLAC_METADATA_BLOCK_TYPE_* tokens.
*/
typedef void (* drflac_meta_proc)(void* pUserData, drflac_metadata* pMetadata);
typedef struct
{
void* pUserData;
void* (* onMalloc)(size_t sz, void* pUserData);
void* (* onRealloc)(void* p, size_t sz, void* pUserData);
void (* onFree)(void* p, void* pUserData);
} drflac_allocation_callbacks;
/* Structure for internal use. Only used for decoders opened with drflac_open_memory. */
typedef struct
{
const drflac_uint8* data;
size_t dataSize;
size_t currentReadPos;
} drflac__memory_stream;
/* Structure for internal use. Used for bit streaming. */
typedef struct
{
/* The function to call when more data needs to be read. */
drflac_read_proc onRead;
/* The function to call when the current read position needs to be moved. */
drflac_seek_proc onSeek;
/* The user data to pass around to onRead and onSeek. */
void* pUserData;
/*
The number of unaligned bytes in the L2 cache. This will always be 0 until the end of the stream is hit. At the end of the
stream there will be a number of bytes that don't cleanly fit in an L1 cache line, so we use this variable to know whether
or not the bistreamer needs to run on a slower path to read those last bytes. This will never be more than sizeof(drflac_cache_t).
*/
size_t unalignedByteCount;
/* The content of the unaligned bytes. */
drflac_cache_t unalignedCache;
/* The index of the next valid cache line in the "L2" cache. */
drflac_uint32 nextL2Line;
/* The number of bits that have been consumed by the cache. This is used to determine how many valid bits are remaining. */
drflac_uint32 consumedBits;
/*
The cached data which was most recently read from the client. There are two levels of cache. Data flows as such:
Client -> L2 -> L1. The L2 -> L1 movement is aligned and runs on a fast path in just a few instructions.
*/
drflac_cache_t cacheL2[DR_FLAC_BUFFER_SIZE/sizeof(drflac_cache_t)];
drflac_cache_t cache;
/*
CRC-16. This is updated whenever bits are read from the bit stream. Manually set this to 0 to reset the CRC. For FLAC, this
is reset to 0 at the beginning of each frame.
*/
drflac_uint16 crc16;
drflac_cache_t crc16Cache; /* A cache for optimizing CRC calculations. This is filled when when the L1 cache is reloaded. */
drflac_uint32 crc16CacheIgnoredBytes; /* The number of bytes to ignore when updating the CRC-16 from the CRC-16 cache. */
} drflac_bs;
typedef struct
{
/* The type of the subframe: SUBFRAME_CONSTANT, SUBFRAME_VERBATIM, SUBFRAME_FIXED or SUBFRAME_LPC. */
drflac_uint8 subframeType;
/* The number of wasted bits per sample as specified by the sub-frame header. */
drflac_uint8 wastedBitsPerSample;
/* The order to use for the prediction stage for SUBFRAME_FIXED and SUBFRAME_LPC. */
drflac_uint8 lpcOrder;
/* A pointer to the buffer containing the decoded samples in the subframe. This pointer is an offset from drflac::pExtraData. */
drflac_int32* pSamplesS32;
} drflac_subframe;
typedef struct
{
/*
If the stream uses variable block sizes, this will be set to the index of the first PCM frame. If fixed block sizes are used, this will
always be set to 0. This is 64-bit because the decoded PCM frame number will be 36 bits.
*/
drflac_uint64 pcmFrameNumber;
/*
If the stream uses fixed block sizes, this will be set to the frame number. If variable block sizes are used, this will always be 0. This
is 32-bit because in fixed block sizes, the maximum frame number will be 31 bits.
*/
drflac_uint32 flacFrameNumber;
/* The sample rate of this frame. */
drflac_uint32 sampleRate;
/* The number of PCM frames in each sub-frame within this frame. */
drflac_uint16 blockSizeInPCMFrames;
/*
The channel assignment of this frame. This is not always set to the channel count. If interchannel decorrelation is being used this
will be set to DRFLAC_CHANNEL_ASSIGNMENT_LEFT_SIDE, DRFLAC_CHANNEL_ASSIGNMENT_RIGHT_SIDE or DRFLAC_CHANNEL_ASSIGNMENT_MID_SIDE.
*/
drflac_uint8 channelAssignment;
/* The number of bits per sample within this frame. */
drflac_uint8 bitsPerSample;
/* The frame's CRC. */
drflac_uint8 crc8;
} drflac_frame_header;
typedef struct
{
/* The header. */
drflac_frame_header header;
/*
The number of PCM frames left to be read in this FLAC frame. This is initially set to the block size. As PCM frames are read,
this will be decremented. When it reaches 0, the decoder will see this frame as fully consumed and load the next frame.
*/
drflac_uint32 pcmFramesRemaining;
/* The list of sub-frames within the frame. There is one sub-frame for each channel, and there's a maximum of 8 channels. */
drflac_subframe subframes[8];
} drflac_frame;
typedef struct
{
/* The function to call when a metadata block is read. */
drflac_meta_proc onMeta;
/* The user data posted to the metadata callback function. */
void* pUserDataMD;
/* Memory allocation callbacks. */
drflac_allocation_callbacks allocationCallbacks;
/* The sample rate. Will be set to something like 44100. */
drflac_uint32 sampleRate;
/*
The number of channels. This will be set to 1 for monaural streams, 2 for stereo, etc. Maximum 8. This is set based on the
value specified in the STREAMINFO block.
*/
drflac_uint8 channels;
/* The bits per sample. Will be set to something like 16, 24, etc. */
drflac_uint8 bitsPerSample;
/* The maximum block size, in samples. This number represents the number of samples in each channel (not combined). */
drflac_uint16 maxBlockSizeInPCMFrames;
/*
The total number of PCM Frames making up the stream. Can be 0 in which case it's still a valid stream, but just means
the total PCM frame count is unknown. Likely the case with streams like internet radio.
*/
drflac_uint64 totalPCMFrameCount;
/* The container type. This is set based on whether or not the decoder was opened from a native or Ogg stream. */
drflac_container container;
/* The number of seekpoints in the seektable. */
drflac_uint32 seekpointCount;
/* Information about the frame the decoder is currently sitting on. */
drflac_frame currentFLACFrame;
/* The index of the PCM frame the decoder is currently sitting on. This is only used for seeking. */
drflac_uint64 currentPCMFrame;
/* The position of the first FLAC frame in the stream. This is only ever used for seeking. */
drflac_uint64 firstFLACFramePosInBytes;
/* A hack to avoid a malloc() when opening a decoder with drflac_open_memory(). */
drflac__memory_stream memoryStream;
/* A pointer to the decoded sample data. This is an offset of pExtraData. */
drflac_int32* pDecodedSamples;
/* A pointer to the seek table. This is an offset of pExtraData, or NULL if there is no seek table. */
drflac_seekpoint* pSeekpoints;
/* Internal use only. Only used with Ogg containers. Points to a drflac_oggbs object. This is an offset of pExtraData. */
void* _oggbs;
/* Internal use only. Used for profiling and testing different seeking modes. */
drflac_bool32 _noSeekTableSeek : 1;
drflac_bool32 _noBinarySearchSeek : 1;
drflac_bool32 _noBruteForceSeek : 1;
/* The bit streamer. The raw FLAC data is fed through this object. */
drflac_bs bs;
/* Variable length extra data. We attach this to the end of the object so we can avoid unnecessary mallocs. */
drflac_uint8 pExtraData[1];
} drflac;
/*
Opens a FLAC decoder.
Parameters
----------
onRead (in)
The function to call when data needs to be read from the client.
onSeek (in)
The function to call when the read position of the client data needs to move.
pUserData (in, optional)
A pointer to application defined data that will be passed to onRead and onSeek.
pAllocationCallbacks (in, optional)
A pointer to application defined callbacks for managing memory allocations.
Return Value
------------
Returns a pointer to an object representing the decoder.
Remarks
-------
Close the decoder with `drflac_close()`.
`pAllocationCallbacks` can be NULL in which case it will use `DRFLAC_MALLOC`, `DRFLAC_REALLOC` and `DRFLAC_FREE`.
This function will automatically detect whether or not you are attempting to open a native or Ogg encapsulated FLAC, both of which should work seamlessly
without any manual intervention. Ogg encapsulation also works with multiplexed streams which basically means it can play FLAC encoded audio tracks in videos.
This is the lowest level function for opening a FLAC stream. You can also use `drflac_open_file()` and `drflac_open_memory()` to open the stream from a file or
from a block of memory respectively.
The STREAMINFO block must be present for this to succeed. Use `drflac_open_relaxed()` to open a FLAC stream where the header may not be present.
Use `drflac_open_with_metadata()` if you need access to metadata.
Seek Also
---------
drflac_open_file()
drflac_open_memory()
drflac_open_with_metadata()
drflac_close()
*/
DRFLAC_API drflac* drflac_open(drflac_read_proc onRead, drflac_seek_proc onSeek, void* pUserData, const drflac_allocation_callbacks* pAllocationCallbacks);
/*
Opens a FLAC stream with relaxed validation of the header block.
Parameters
----------
onRead (in)
The function to call when data needs to be read from the client.
onSeek (in)
The function to call when the read position of the client data needs to move.
container (in)
Whether or not the FLAC stream is encapsulated using standard FLAC encapsulation or Ogg encapsulation.
pUserData (in, optional)
A pointer to application defined data that will be passed to onRead and onSeek.
pAllocationCallbacks (in, optional)
A pointer to application defined callbacks for managing memory allocations.
Return Value
------------
A pointer to an object representing the decoder.
Remarks
-------
The same as drflac_open(), except attempts to open the stream even when a header block is not present.
Because the header is not necessarily available, the caller must explicitly define the container (Native or Ogg). Do not set this to `drflac_container_unknown`
as that is for internal use only.
Opening in relaxed mode will continue reading data from onRead until it finds a valid frame. If a frame is never found it will continue forever. To abort,
force your `onRead` callback to return 0, which dr_flac will use as an indicator that the end of the stream was found.
Use `drflac_open_with_metadata_relaxed()` if you need access to metadata.
*/
DRFLAC_API drflac* drflac_open_relaxed(drflac_read_proc onRead, drflac_seek_proc onSeek, drflac_container container, void* pUserData, const drflac_allocation_callbacks* pAllocationCallbacks);
/*
Opens a FLAC decoder and notifies the caller of the metadata chunks (album art, etc.).
Parameters
----------
onRead (in)
The function to call when data needs to be read from the client.
onSeek (in)
The function to call when the read position of the client data needs to move.
onMeta (in)
The function to call for every metadata block.
pUserData (in, optional)
A pointer to application defined data that will be passed to onRead, onSeek and onMeta.
pAllocationCallbacks (in, optional)
A pointer to application defined callbacks for managing memory allocations.
Return Value
------------
A pointer to an object representing the decoder.
Remarks
-------
Close the decoder with `drflac_close()`.
`pAllocationCallbacks` can be NULL in which case it will use `DRFLAC_MALLOC`, `DRFLAC_REALLOC` and `DRFLAC_FREE`.
This is slower than `drflac_open()`, so avoid this one if you don't need metadata. Internally, this will allocate and free memory on the heap for every
metadata block except for STREAMINFO and PADDING blocks.
The caller is notified of the metadata via the `onMeta` callback. All metadata blocks will be handled before the function returns. This callback takes a
pointer to a `drflac_metadata` object which is a union containing the data of all relevant metadata blocks. Use the `type` member to discriminate against
the different metadata types.
The STREAMINFO block must be present for this to succeed. Use `drflac_open_with_metadata_relaxed()` to open a FLAC stream where the header may not be present.
Note that this will behave inconsistently with `drflac_open()` if the stream is an Ogg encapsulated stream and a metadata block is corrupted. This is due to
the way the Ogg stream recovers from corrupted pages. When `drflac_open_with_metadata()` is being used, the open routine will try to read the contents of the
metadata block, whereas `drflac_open()` will simply seek past it (for the sake of efficiency). This inconsistency can result in different samples being
returned depending on whether or not the stream is being opened with metadata.
Seek Also
---------
drflac_open_file_with_metadata()
drflac_open_memory_with_metadata()
drflac_open()
drflac_close()
*/
DRFLAC_API drflac* drflac_open_with_metadata(drflac_read_proc onRead, drflac_seek_proc onSeek, drflac_meta_proc onMeta, void* pUserData, const drflac_allocation_callbacks* pAllocationCallbacks);
/*
The same as drflac_open_with_metadata(), except attempts to open the stream even when a header block is not present.
See Also
--------
drflac_open_with_metadata()
drflac_open_relaxed()
*/
DRFLAC_API drflac* drflac_open_with_metadata_relaxed(drflac_read_proc onRead, drflac_seek_proc onSeek, drflac_meta_proc onMeta, drflac_container container, void* pUserData, const drflac_allocation_callbacks* pAllocationCallbacks);
/*
Closes the given FLAC decoder.
Parameters
----------
pFlac (in)
The decoder to close.
Remarks
-------
This will destroy the decoder object.
See Also
--------
drflac_open()
drflac_open_with_metadata()
drflac_open_file()
drflac_open_file_w()
drflac_open_file_with_metadata()
drflac_open_file_with_metadata_w()
drflac_open_memory()
drflac_open_memory_with_metadata()
*/
DRFLAC_API void drflac_close(drflac* pFlac);
/*
Reads sample data from the given FLAC decoder, output as interleaved signed 32-bit PCM.
Parameters
----------
pFlac (in)
The decoder.
framesToRead (in)
The number of PCM frames to read.
pBufferOut (out, optional)
A pointer to the buffer that will receive the decoded samples.
Return Value
------------
Returns the number of PCM frames actually read. If the return value is less than `framesToRead` it has reached the end.
Remarks
-------
pBufferOut can be null, in which case the call will act as a seek, and the return value will be the number of frames seeked.
*/
DRFLAC_API drflac_uint64 drflac_read_pcm_frames_s32(drflac* pFlac, drflac_uint64 framesToRead, drflac_int32* pBufferOut);
/*
Reads sample data from the given FLAC decoder, output as interleaved signed 16-bit PCM.
Parameters
----------
pFlac (in)
The decoder.
framesToRead (in)
The number of PCM frames to read.
pBufferOut (out, optional)
A pointer to the buffer that will receive the decoded samples.
Return Value
------------
Returns the number of PCM frames actually read. If the return value is less than `framesToRead` it has reached the end.