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dr_mp3.h
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dr_mp3.h
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/*
MP3 audio decoder. Choice of public domain or MIT-0. See license statements at the end of this file.
dr_mp3 - v0.6.39 - 2024-02-27
David Reid - mackron@gmail.com
GitHub: https://github.com/mackron/dr_libs
Based on minimp3 (https://github.com/lieff/minimp3) which is where the real work was done. See the bottom of this file for differences between minimp3 and dr_mp3.
*/
/*
RELEASE NOTES - VERSION 0.6
===========================
Version 0.6 includes breaking changes with the configuration of decoders. The ability to customize the number of output channels and the sample rate has been
removed. You must now use the channel count and sample rate reported by the MP3 stream itself, and all channel and sample rate conversion must be done
yourself.
Changes to Initialization
-------------------------
Previously, `drmp3_init()`, etc. took a pointer to a `drmp3_config` object that allowed you to customize the output channels and sample rate. This has been
removed. If you need the old behaviour you will need to convert the data yourself or just not upgrade. The following APIs have changed.
`drmp3_init()`
`drmp3_init_memory()`
`drmp3_init_file()`
Miscellaneous Changes
---------------------
Support for loading a file from a `wchar_t` string has been added via the `drmp3_init_file_w()` API.
*/
/*
Introducation
=============
dr_mp3 is a single file library. To use it, do something like the following in one .c file.
```c
#define DR_MP3_IMPLEMENTATION
#include "dr_mp3.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
drmp3 mp3;
if (!drmp3_init_file(&mp3, "MySong.mp3", NULL)) {
// Failed to open file
}
...
drmp3_uint64 framesRead = drmp3_read_pcm_frames_f32(pMP3, framesToRead, pFrames);
```
The drmp3 object is transparent so you can get access to the channel count and sample rate like so:
```
drmp3_uint32 channels = mp3.channels;
drmp3_uint32 sampleRate = mp3.sampleRate;
```
The example above initializes a decoder from a file, but you can also initialize it from a block of memory and read and seek callbacks with
`drmp3_init_memory()` and `drmp3_init()` respectively.
You do not need to do any annoying memory management when reading PCM frames - this is all managed internally. You can request any number of PCM frames in each
call to `drmp3_read_pcm_frames_f32()` and it will return as many PCM frames as it can, up to the requested amount.
You can also decode an entire file in one go with `drmp3_open_and_read_pcm_frames_f32()`, `drmp3_open_memory_and_read_pcm_frames_f32()` and
`drmp3_open_file_and_read_pcm_frames_f32()`.
Build Options
=============
#define these options before including this file.
#define DR_MP3_NO_STDIO
Disable drmp3_init_file(), etc.
#define DR_MP3_NO_SIMD
Disable SIMD optimizations.
*/
#ifndef dr_mp3_h
#define dr_mp3_h
#ifdef __cplusplus
extern "C" {
#endif
#define DRMP3_STRINGIFY(x) #x
#define DRMP3_XSTRINGIFY(x) DRMP3_STRINGIFY(x)
#define DRMP3_VERSION_MAJOR 0
#define DRMP3_VERSION_MINOR 6
#define DRMP3_VERSION_REVISION 39
#define DRMP3_VERSION_STRING DRMP3_XSTRINGIFY(DRMP3_VERSION_MAJOR) "." DRMP3_XSTRINGIFY(DRMP3_VERSION_MINOR) "." DRMP3_XSTRINGIFY(DRMP3_VERSION_REVISION)
#include <stddef.h> /* For size_t. */
/* Sized Types */
typedef signed char drmp3_int8;
typedef unsigned char drmp3_uint8;
typedef signed short drmp3_int16;
typedef unsigned short drmp3_uint16;
typedef signed int drmp3_int32;
typedef unsigned int drmp3_uint32;
#if defined(_MSC_VER) && !defined(__clang__)
typedef signed __int64 drmp3_int64;
typedef unsigned __int64 drmp3_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 drmp3_int64;
typedef unsigned long long drmp3_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 drmp3_uint64 drmp3_uintptr;
#else
typedef drmp3_uint32 drmp3_uintptr;
#endif
typedef drmp3_uint8 drmp3_bool8;
typedef drmp3_uint32 drmp3_bool32;
#define DRMP3_TRUE 1
#define DRMP3_FALSE 0
/* End Sized Types */
/* Decorations */
#if !defined(DRMP3_API)
#if defined(DRMP3_DLL)
#if defined(_WIN32)
#define DRMP3_DLL_IMPORT __declspec(dllimport)
#define DRMP3_DLL_EXPORT __declspec(dllexport)
#define DRMP3_DLL_PRIVATE static
#else
#if defined(__GNUC__) && __GNUC__ >= 4
#define DRMP3_DLL_IMPORT __attribute__((visibility("default")))
#define DRMP3_DLL_EXPORT __attribute__((visibility("default")))
#define DRMP3_DLL_PRIVATE __attribute__((visibility("hidden")))
#else
#define DRMP3_DLL_IMPORT
#define DRMP3_DLL_EXPORT
#define DRMP3_DLL_PRIVATE static
#endif
#endif
#if defined(DR_MP3_IMPLEMENTATION) || defined(DRMP3_IMPLEMENTATION)
#define DRMP3_API DRMP3_DLL_EXPORT
#else
#define DRMP3_API DRMP3_DLL_IMPORT
#endif
#define DRMP3_PRIVATE DRMP3_DLL_PRIVATE
#else
#define DRMP3_API extern
#define DRMP3_PRIVATE static
#endif
#endif
/* End Decorations */
/* Result Codes */
typedef drmp3_int32 drmp3_result;
#define DRMP3_SUCCESS 0
#define DRMP3_ERROR -1 /* A generic error. */
#define DRMP3_INVALID_ARGS -2
#define DRMP3_INVALID_OPERATION -3
#define DRMP3_OUT_OF_MEMORY -4
#define DRMP3_OUT_OF_RANGE -5
#define DRMP3_ACCESS_DENIED -6
#define DRMP3_DOES_NOT_EXIST -7
#define DRMP3_ALREADY_EXISTS -8
#define DRMP3_TOO_MANY_OPEN_FILES -9
#define DRMP3_INVALID_FILE -10
#define DRMP3_TOO_BIG -11
#define DRMP3_PATH_TOO_LONG -12
#define DRMP3_NAME_TOO_LONG -13
#define DRMP3_NOT_DIRECTORY -14
#define DRMP3_IS_DIRECTORY -15
#define DRMP3_DIRECTORY_NOT_EMPTY -16
#define DRMP3_END_OF_FILE -17
#define DRMP3_NO_SPACE -18
#define DRMP3_BUSY -19
#define DRMP3_IO_ERROR -20
#define DRMP3_INTERRUPT -21
#define DRMP3_UNAVAILABLE -22
#define DRMP3_ALREADY_IN_USE -23
#define DRMP3_BAD_ADDRESS -24
#define DRMP3_BAD_SEEK -25
#define DRMP3_BAD_PIPE -26
#define DRMP3_DEADLOCK -27
#define DRMP3_TOO_MANY_LINKS -28
#define DRMP3_NOT_IMPLEMENTED -29
#define DRMP3_NO_MESSAGE -30
#define DRMP3_BAD_MESSAGE -31
#define DRMP3_NO_DATA_AVAILABLE -32
#define DRMP3_INVALID_DATA -33
#define DRMP3_TIMEOUT -34
#define DRMP3_NO_NETWORK -35
#define DRMP3_NOT_UNIQUE -36
#define DRMP3_NOT_SOCKET -37
#define DRMP3_NO_ADDRESS -38
#define DRMP3_BAD_PROTOCOL -39
#define DRMP3_PROTOCOL_UNAVAILABLE -40
#define DRMP3_PROTOCOL_NOT_SUPPORTED -41
#define DRMP3_PROTOCOL_FAMILY_NOT_SUPPORTED -42
#define DRMP3_ADDRESS_FAMILY_NOT_SUPPORTED -43
#define DRMP3_SOCKET_NOT_SUPPORTED -44
#define DRMP3_CONNECTION_RESET -45
#define DRMP3_ALREADY_CONNECTED -46
#define DRMP3_NOT_CONNECTED -47
#define DRMP3_CONNECTION_REFUSED -48
#define DRMP3_NO_HOST -49
#define DRMP3_IN_PROGRESS -50
#define DRMP3_CANCELLED -51
#define DRMP3_MEMORY_ALREADY_MAPPED -52
#define DRMP3_AT_END -53
/* End Result Codes */
#define DRMP3_MAX_PCM_FRAMES_PER_MP3_FRAME 1152
#define DRMP3_MAX_SAMPLES_PER_FRAME (DRMP3_MAX_PCM_FRAMES_PER_MP3_FRAME*2)
/* Inline */
#ifdef _MSC_VER
#define DRMP3_INLINE __forceinline
#elif defined(__GNUC__)
/*
I've had a bug report where GCC is emitting warnings about functions possibly not being inlineable. This warning happens when
the __attribute__((always_inline)) attribute is defined without an "inline" statement. I think therefore there must be some
case where "__inline__" is not always defined, thus the compiler emitting these warnings. When using -std=c89 or -ansi on the
command line, we cannot use the "inline" keyword and instead need to use "__inline__". In an attempt to work around this issue
I am using "__inline__" only when we're compiling in strict ANSI mode.
*/
#if defined(__STRICT_ANSI__)
#define DRMP3_GNUC_INLINE_HINT __inline__
#else
#define DRMP3_GNUC_INLINE_HINT inline
#endif
#if (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 2)) || defined(__clang__)
#define DRMP3_INLINE DRMP3_GNUC_INLINE_HINT __attribute__((always_inline))
#else
#define DRMP3_INLINE DRMP3_GNUC_INLINE_HINT
#endif
#elif defined(__WATCOMC__)
#define DRMP3_INLINE __inline
#else
#define DRMP3_INLINE
#endif
/* End Inline */
DRMP3_API void drmp3_version(drmp3_uint32* pMajor, drmp3_uint32* pMinor, drmp3_uint32* pRevision);
DRMP3_API const char* drmp3_version_string(void);
/* Allocation Callbacks */
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);
} drmp3_allocation_callbacks;
/* End Allocation Callbacks */
/*
Low Level Push API
==================
*/
typedef struct
{
int frame_bytes, channels, hz, layer, bitrate_kbps;
} drmp3dec_frame_info;
typedef struct
{
float mdct_overlap[2][9*32], qmf_state[15*2*32];
int reserv, free_format_bytes;
drmp3_uint8 header[4], reserv_buf[511];
} drmp3dec;
/* Initializes a low level decoder. */
DRMP3_API void drmp3dec_init(drmp3dec *dec);
/* Reads a frame from a low level decoder. */
DRMP3_API int drmp3dec_decode_frame(drmp3dec *dec, const drmp3_uint8 *mp3, int mp3_bytes, void *pcm, drmp3dec_frame_info *info);
/* Helper for converting between f32 and s16. */
DRMP3_API void drmp3dec_f32_to_s16(const float *in, drmp3_int16 *out, size_t num_samples);
/*
Main API (Pull API)
===================
*/
typedef enum
{
drmp3_seek_origin_start,
drmp3_seek_origin_current
} drmp3_seek_origin;
typedef struct
{
drmp3_uint64 seekPosInBytes; /* Points to the first byte of an MP3 frame. */
drmp3_uint64 pcmFrameIndex; /* The index of the PCM frame this seek point targets. */
drmp3_uint16 mp3FramesToDiscard; /* The number of whole MP3 frames to be discarded before pcmFramesToDiscard. */
drmp3_uint16 pcmFramesToDiscard; /* The number of leading samples to read and discard. These are discarded after mp3FramesToDiscard. */
} drmp3_seek_point;
/*
Callback for when data is read. Return value is the number of bytes actually read.
pUserData [in] The user data that was passed to drmp3_init(), drmp3_open() and family.
pBufferOut [out] The output buffer.
bytesToRead [in] The number of bytes to read.
Returns the number of bytes actually read.
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 (* drmp3_read_proc)(void* pUserData, void* pBufferOut, size_t bytesToRead);
/*
Callback for when data needs to be seeked.
pUserData [in] The user data that was passed to drmp3_init(), drmp3_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.
Returns whether or not the seek was successful.
Whether or not it is relative to the beginning or current position is determined by the "origin" parameter which
will be either drmp3_seek_origin_start or drmp3_seek_origin_current.
*/
typedef drmp3_bool32 (* drmp3_seek_proc)(void* pUserData, int offset, drmp3_seek_origin origin);
typedef struct
{
drmp3_uint32 channels;
drmp3_uint32 sampleRate;
} drmp3_config;
typedef struct
{
drmp3dec decoder;
drmp3_uint32 channels;
drmp3_uint32 sampleRate;
drmp3_read_proc onRead;
drmp3_seek_proc onSeek;
void* pUserData;
drmp3_allocation_callbacks allocationCallbacks;
drmp3_uint32 mp3FrameChannels; /* The number of channels in the currently loaded MP3 frame. Internal use only. */
drmp3_uint32 mp3FrameSampleRate; /* The sample rate of the currently loaded MP3 frame. Internal use only. */
drmp3_uint32 pcmFramesConsumedInMP3Frame;
drmp3_uint32 pcmFramesRemainingInMP3Frame;
drmp3_uint8 pcmFrames[sizeof(float)*DRMP3_MAX_SAMPLES_PER_FRAME]; /* <-- Multipled by sizeof(float) to ensure there's enough room for DR_MP3_FLOAT_OUTPUT. */
drmp3_uint64 currentPCMFrame; /* The current PCM frame, globally, based on the output sample rate. Mainly used for seeking. */
drmp3_uint64 streamCursor; /* The current byte the decoder is sitting on in the raw stream. */
drmp3_seek_point* pSeekPoints; /* NULL by default. Set with drmp3_bind_seek_table(). Memory is owned by the client. dr_mp3 will never attempt to free this pointer. */
drmp3_uint32 seekPointCount; /* The number of items in pSeekPoints. When set to 0 assumes to no seek table. Defaults to zero. */
size_t dataSize;
size_t dataCapacity;
size_t dataConsumed;
drmp3_uint8* pData;
drmp3_bool32 atEnd : 1;
struct
{
const drmp3_uint8* pData;
size_t dataSize;
size_t currentReadPos;
} memory; /* Only used for decoders that were opened against a block of memory. */
} drmp3;
/*
Initializes an MP3 decoder.
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.
Returns true if successful; false otherwise.
Close the loader with drmp3_uninit().
See also: drmp3_init_file(), drmp3_init_memory(), drmp3_uninit()
*/
DRMP3_API drmp3_bool32 drmp3_init(drmp3* pMP3, drmp3_read_proc onRead, drmp3_seek_proc onSeek, void* pUserData, const drmp3_allocation_callbacks* pAllocationCallbacks);
/*
Initializes an MP3 decoder from a block of memory.
This does not create a copy of the data. It is up to the application to ensure the buffer remains valid for
the lifetime of the drmp3 object.
The buffer should contain the contents of the entire MP3 file.
*/
DRMP3_API drmp3_bool32 drmp3_init_memory(drmp3* pMP3, const void* pData, size_t dataSize, const drmp3_allocation_callbacks* pAllocationCallbacks);
#ifndef DR_MP3_NO_STDIO
/*
Initializes an MP3 decoder from a file.
This holds the internal FILE object until drmp3_uninit() is called. Keep this in mind if you're caching drmp3
objects because the operating system may restrict the number of file handles an application can have open at
any given time.
*/
DRMP3_API drmp3_bool32 drmp3_init_file(drmp3* pMP3, const char* pFilePath, const drmp3_allocation_callbacks* pAllocationCallbacks);
DRMP3_API drmp3_bool32 drmp3_init_file_w(drmp3* pMP3, const wchar_t* pFilePath, const drmp3_allocation_callbacks* pAllocationCallbacks);
#endif
/*
Uninitializes an MP3 decoder.
*/
DRMP3_API void drmp3_uninit(drmp3* pMP3);
/*
Reads PCM frames as interleaved 32-bit IEEE floating point PCM.
Note that framesToRead specifies the number of PCM frames to read, _not_ the number of MP3 frames.
*/
DRMP3_API drmp3_uint64 drmp3_read_pcm_frames_f32(drmp3* pMP3, drmp3_uint64 framesToRead, float* pBufferOut);
/*
Reads PCM frames as interleaved signed 16-bit integer PCM.
Note that framesToRead specifies the number of PCM frames to read, _not_ the number of MP3 frames.
*/
DRMP3_API drmp3_uint64 drmp3_read_pcm_frames_s16(drmp3* pMP3, drmp3_uint64 framesToRead, drmp3_int16* pBufferOut);
/*
Seeks to a specific frame.
Note that this is _not_ an MP3 frame, but rather a PCM frame.
*/
DRMP3_API drmp3_bool32 drmp3_seek_to_pcm_frame(drmp3* pMP3, drmp3_uint64 frameIndex);
/*
Calculates the total number of PCM frames in the MP3 stream. Cannot be used for infinite streams such as internet
radio. Runs in linear time. Returns 0 on error.
*/
DRMP3_API drmp3_uint64 drmp3_get_pcm_frame_count(drmp3* pMP3);
/*
Calculates the total number of MP3 frames in the MP3 stream. Cannot be used for infinite streams such as internet
radio. Runs in linear time. Returns 0 on error.
*/
DRMP3_API drmp3_uint64 drmp3_get_mp3_frame_count(drmp3* pMP3);
/*
Calculates the total number of MP3 and PCM frames in the MP3 stream. Cannot be used for infinite streams such as internet
radio. Runs in linear time. Returns 0 on error.
This is equivalent to calling drmp3_get_mp3_frame_count() and drmp3_get_pcm_frame_count() except that it's more efficient.
*/
DRMP3_API drmp3_bool32 drmp3_get_mp3_and_pcm_frame_count(drmp3* pMP3, drmp3_uint64* pMP3FrameCount, drmp3_uint64* pPCMFrameCount);
/*
Calculates the seekpoints based on PCM frames. This is slow.
pSeekpoint count is a pointer to a uint32 containing the seekpoint count. On input it contains the desired count.
On output it contains the actual count. The reason for this design is that the client may request too many
seekpoints, in which case dr_mp3 will return a corrected count.
Note that seektable seeking is not quite sample exact when the MP3 stream contains inconsistent sample rates.
*/
DRMP3_API drmp3_bool32 drmp3_calculate_seek_points(drmp3* pMP3, drmp3_uint32* pSeekPointCount, drmp3_seek_point* pSeekPoints);
/*
Binds a seek table to the decoder.
This does _not_ make a copy of pSeekPoints - it only references it. It is up to the application to ensure this
remains valid while it is bound to the decoder.
Use drmp3_calculate_seek_points() to calculate the seek points.
*/
DRMP3_API drmp3_bool32 drmp3_bind_seek_table(drmp3* pMP3, drmp3_uint32 seekPointCount, drmp3_seek_point* pSeekPoints);
/*
Opens an decodes an entire MP3 stream as a single operation.
On output pConfig will receive the channel count and sample rate of the stream.
Free the returned pointer with drmp3_free().
*/
DRMP3_API float* drmp3_open_and_read_pcm_frames_f32(drmp3_read_proc onRead, drmp3_seek_proc onSeek, void* pUserData, drmp3_config* pConfig, drmp3_uint64* pTotalFrameCount, const drmp3_allocation_callbacks* pAllocationCallbacks);
DRMP3_API drmp3_int16* drmp3_open_and_read_pcm_frames_s16(drmp3_read_proc onRead, drmp3_seek_proc onSeek, void* pUserData, drmp3_config* pConfig, drmp3_uint64* pTotalFrameCount, const drmp3_allocation_callbacks* pAllocationCallbacks);
DRMP3_API float* drmp3_open_memory_and_read_pcm_frames_f32(const void* pData, size_t dataSize, drmp3_config* pConfig, drmp3_uint64* pTotalFrameCount, const drmp3_allocation_callbacks* pAllocationCallbacks);
DRMP3_API drmp3_int16* drmp3_open_memory_and_read_pcm_frames_s16(const void* pData, size_t dataSize, drmp3_config* pConfig, drmp3_uint64* pTotalFrameCount, const drmp3_allocation_callbacks* pAllocationCallbacks);
#ifndef DR_MP3_NO_STDIO
DRMP3_API float* drmp3_open_file_and_read_pcm_frames_f32(const char* filePath, drmp3_config* pConfig, drmp3_uint64* pTotalFrameCount, const drmp3_allocation_callbacks* pAllocationCallbacks);
DRMP3_API drmp3_int16* drmp3_open_file_and_read_pcm_frames_s16(const char* filePath, drmp3_config* pConfig, drmp3_uint64* pTotalFrameCount, const drmp3_allocation_callbacks* pAllocationCallbacks);
#endif
/*
Allocates a block of memory on the heap.
*/
DRMP3_API void* drmp3_malloc(size_t sz, const drmp3_allocation_callbacks* pAllocationCallbacks);
/*
Frees any memory that was allocated by a public drmp3 API.
*/
DRMP3_API void drmp3_free(void* p, const drmp3_allocation_callbacks* pAllocationCallbacks);
#ifdef __cplusplus
}
#endif
#endif /* dr_mp3_h */
/************************************************************************************************************************************************************
************************************************************************************************************************************************************
IMPLEMENTATION
************************************************************************************************************************************************************
************************************************************************************************************************************************************/
#if defined(DR_MP3_IMPLEMENTATION) || defined(DRMP3_IMPLEMENTATION)
#ifndef dr_mp3_c
#define dr_mp3_c
#include <stdlib.h>
#include <string.h>
#include <limits.h> /* For INT_MAX */
DRMP3_API void drmp3_version(drmp3_uint32* pMajor, drmp3_uint32* pMinor, drmp3_uint32* pRevision)
{
if (pMajor) {
*pMajor = DRMP3_VERSION_MAJOR;
}
if (pMinor) {
*pMinor = DRMP3_VERSION_MINOR;
}
if (pRevision) {
*pRevision = DRMP3_VERSION_REVISION;
}
}
DRMP3_API const char* drmp3_version_string(void)
{
return DRMP3_VERSION_STRING;
}
/* Disable SIMD when compiling with TCC for now. */
#if defined(__TINYC__)
#define DR_MP3_NO_SIMD
#endif
#define DRMP3_OFFSET_PTR(p, offset) ((void*)((drmp3_uint8*)(p) + (offset)))
#define DRMP3_MAX_FREE_FORMAT_FRAME_SIZE 2304 /* more than ISO spec's */
#ifndef DRMP3_MAX_FRAME_SYNC_MATCHES
#define DRMP3_MAX_FRAME_SYNC_MATCHES 10
#endif
#define DRMP3_MAX_L3_FRAME_PAYLOAD_BYTES DRMP3_MAX_FREE_FORMAT_FRAME_SIZE /* MUST be >= 320000/8/32000*1152 = 1440 */
#define DRMP3_MAX_BITRESERVOIR_BYTES 511
#define DRMP3_SHORT_BLOCK_TYPE 2
#define DRMP3_STOP_BLOCK_TYPE 3
#define DRMP3_MODE_MONO 3
#define DRMP3_MODE_JOINT_STEREO 1
#define DRMP3_HDR_SIZE 4
#define DRMP3_HDR_IS_MONO(h) (((h[3]) & 0xC0) == 0xC0)
#define DRMP3_HDR_IS_MS_STEREO(h) (((h[3]) & 0xE0) == 0x60)
#define DRMP3_HDR_IS_FREE_FORMAT(h) (((h[2]) & 0xF0) == 0)
#define DRMP3_HDR_IS_CRC(h) (!((h[1]) & 1))
#define DRMP3_HDR_TEST_PADDING(h) ((h[2]) & 0x2)
#define DRMP3_HDR_TEST_MPEG1(h) ((h[1]) & 0x8)
#define DRMP3_HDR_TEST_NOT_MPEG25(h) ((h[1]) & 0x10)
#define DRMP3_HDR_TEST_I_STEREO(h) ((h[3]) & 0x10)
#define DRMP3_HDR_TEST_MS_STEREO(h) ((h[3]) & 0x20)
#define DRMP3_HDR_GET_STEREO_MODE(h) (((h[3]) >> 6) & 3)
#define DRMP3_HDR_GET_STEREO_MODE_EXT(h) (((h[3]) >> 4) & 3)
#define DRMP3_HDR_GET_LAYER(h) (((h[1]) >> 1) & 3)
#define DRMP3_HDR_GET_BITRATE(h) ((h[2]) >> 4)
#define DRMP3_HDR_GET_SAMPLE_RATE(h) (((h[2]) >> 2) & 3)
#define DRMP3_HDR_GET_MY_SAMPLE_RATE(h) (DRMP3_HDR_GET_SAMPLE_RATE(h) + (((h[1] >> 3) & 1) + ((h[1] >> 4) & 1))*3)
#define DRMP3_HDR_IS_FRAME_576(h) ((h[1] & 14) == 2)
#define DRMP3_HDR_IS_LAYER_1(h) ((h[1] & 6) == 6)
#define DRMP3_BITS_DEQUANTIZER_OUT -1
#define DRMP3_MAX_SCF (255 + DRMP3_BITS_DEQUANTIZER_OUT*4 - 210)
#define DRMP3_MAX_SCFI ((DRMP3_MAX_SCF + 3) & ~3)
#define DRMP3_MIN(a, b) ((a) > (b) ? (b) : (a))
#define DRMP3_MAX(a, b) ((a) < (b) ? (b) : (a))
#if !defined(DR_MP3_NO_SIMD)
#if !defined(DR_MP3_ONLY_SIMD) && (defined(_M_X64) || defined(__x86_64__) || defined(__aarch64__) || defined(_M_ARM64))
/* x64 always have SSE2, arm64 always have neon, no need for generic code */
#define DR_MP3_ONLY_SIMD
#endif
#if ((defined(_MSC_VER) && _MSC_VER >= 1400) && defined(_M_X64)) || ((defined(__i386) || defined(_M_IX86) || defined(__i386__) || defined(__x86_64__)) && ((defined(_M_IX86_FP) && _M_IX86_FP == 2) || defined(__SSE2__)))
#if defined(_MSC_VER)
#include <intrin.h>
#endif
#include <emmintrin.h>
#define DRMP3_HAVE_SSE 1
#define DRMP3_HAVE_SIMD 1
#define DRMP3_VSTORE _mm_storeu_ps
#define DRMP3_VLD _mm_loadu_ps
#define DRMP3_VSET _mm_set1_ps
#define DRMP3_VADD _mm_add_ps
#define DRMP3_VSUB _mm_sub_ps
#define DRMP3_VMUL _mm_mul_ps
#define DRMP3_VMAC(a, x, y) _mm_add_ps(a, _mm_mul_ps(x, y))
#define DRMP3_VMSB(a, x, y) _mm_sub_ps(a, _mm_mul_ps(x, y))
#define DRMP3_VMUL_S(x, s) _mm_mul_ps(x, _mm_set1_ps(s))
#define DRMP3_VREV(x) _mm_shuffle_ps(x, x, _MM_SHUFFLE(0, 1, 2, 3))
typedef __m128 drmp3_f4;
#if defined(_MSC_VER) || defined(DR_MP3_ONLY_SIMD)
#define drmp3_cpuid __cpuid
#else
static __inline__ __attribute__((always_inline)) void drmp3_cpuid(int CPUInfo[], const int InfoType)
{
#if defined(__PIC__)
__asm__ __volatile__(
#if defined(__x86_64__)
"push %%rbx\n"
"cpuid\n"
"xchgl %%ebx, %1\n"
"pop %%rbx\n"
#else
"xchgl %%ebx, %1\n"
"cpuid\n"
"xchgl %%ebx, %1\n"
#endif
: "=a" (CPUInfo[0]), "=r" (CPUInfo[1]), "=c" (CPUInfo[2]), "=d" (CPUInfo[3])
: "a" (InfoType));
#else
__asm__ __volatile__(
"cpuid"
: "=a" (CPUInfo[0]), "=b" (CPUInfo[1]), "=c" (CPUInfo[2]), "=d" (CPUInfo[3])
: "a" (InfoType));
#endif
}
#endif
static int drmp3_have_simd(void)
{
#ifdef DR_MP3_ONLY_SIMD
return 1;
#else
static int g_have_simd;
int CPUInfo[4];
#ifdef MINIMP3_TEST
static int g_counter;
if (g_counter++ > 100)
return 0;
#endif
if (g_have_simd)
goto end;
drmp3_cpuid(CPUInfo, 0);
if (CPUInfo[0] > 0)
{
drmp3_cpuid(CPUInfo, 1);
g_have_simd = (CPUInfo[3] & (1 << 26)) + 1; /* SSE2 */
return g_have_simd - 1;
}
end:
return g_have_simd - 1;
#endif
}
#elif defined(__ARM_NEON) || defined(__aarch64__) || defined(_M_ARM64)
#include <arm_neon.h>
#define DRMP3_HAVE_SSE 0
#define DRMP3_HAVE_SIMD 1
#define DRMP3_VSTORE vst1q_f32
#define DRMP3_VLD vld1q_f32
#define DRMP3_VSET vmovq_n_f32
#define DRMP3_VADD vaddq_f32
#define DRMP3_VSUB vsubq_f32
#define DRMP3_VMUL vmulq_f32
#define DRMP3_VMAC(a, x, y) vmlaq_f32(a, x, y)
#define DRMP3_VMSB(a, x, y) vmlsq_f32(a, x, y)
#define DRMP3_VMUL_S(x, s) vmulq_f32(x, vmovq_n_f32(s))
#define DRMP3_VREV(x) vcombine_f32(vget_high_f32(vrev64q_f32(x)), vget_low_f32(vrev64q_f32(x)))
typedef float32x4_t drmp3_f4;
static int drmp3_have_simd(void)
{ /* TODO: detect neon for !DR_MP3_ONLY_SIMD */
return 1;
}
#else
#define DRMP3_HAVE_SSE 0
#define DRMP3_HAVE_SIMD 0
#ifdef DR_MP3_ONLY_SIMD
#error DR_MP3_ONLY_SIMD used, but SSE/NEON not enabled
#endif
#endif
#else
#define DRMP3_HAVE_SIMD 0
#endif
#if defined(__ARM_ARCH) && (__ARM_ARCH >= 6) && !defined(__aarch64__) && !defined(_M_ARM64) && !defined(__ARM_ARCH_6M__)
#define DRMP3_HAVE_ARMV6 1
static __inline__ __attribute__((always_inline)) drmp3_int32 drmp3_clip_int16_arm(drmp3_int32 a)
{
drmp3_int32 x = 0;
__asm__ ("ssat %0, #16, %1" : "=r"(x) : "r"(a));
return x;
}
#else
#define DRMP3_HAVE_ARMV6 0
#endif
/* Standard library stuff. */
#ifndef DRMP3_ASSERT
#include <assert.h>
#define DRMP3_ASSERT(expression) assert(expression)
#endif
#ifndef DRMP3_COPY_MEMORY
#define DRMP3_COPY_MEMORY(dst, src, sz) memcpy((dst), (src), (sz))
#endif
#ifndef DRMP3_MOVE_MEMORY
#define DRMP3_MOVE_MEMORY(dst, src, sz) memmove((dst), (src), (sz))
#endif
#ifndef DRMP3_ZERO_MEMORY
#define DRMP3_ZERO_MEMORY(p, sz) memset((p), 0, (sz))
#endif
#define DRMP3_ZERO_OBJECT(p) DRMP3_ZERO_MEMORY((p), sizeof(*(p)))
#ifndef DRMP3_MALLOC
#define DRMP3_MALLOC(sz) malloc((sz))
#endif
#ifndef DRMP3_REALLOC
#define DRMP3_REALLOC(p, sz) realloc((p), (sz))
#endif
#ifndef DRMP3_FREE
#define DRMP3_FREE(p) free((p))
#endif
typedef struct
{
const drmp3_uint8 *buf;
int pos, limit;
} drmp3_bs;
typedef struct
{
float scf[3*64];
drmp3_uint8 total_bands, stereo_bands, bitalloc[64], scfcod[64];
} drmp3_L12_scale_info;
typedef struct
{
drmp3_uint8 tab_offset, code_tab_width, band_count;
} drmp3_L12_subband_alloc;
typedef struct
{
const drmp3_uint8 *sfbtab;
drmp3_uint16 part_23_length, big_values, scalefac_compress;
drmp3_uint8 global_gain, block_type, mixed_block_flag, n_long_sfb, n_short_sfb;
drmp3_uint8 table_select[3], region_count[3], subblock_gain[3];
drmp3_uint8 preflag, scalefac_scale, count1_table, scfsi;
} drmp3_L3_gr_info;
typedef struct
{
drmp3_bs bs;
drmp3_uint8 maindata[DRMP3_MAX_BITRESERVOIR_BYTES + DRMP3_MAX_L3_FRAME_PAYLOAD_BYTES];
drmp3_L3_gr_info gr_info[4];
float grbuf[2][576], scf[40], syn[18 + 15][2*32];
drmp3_uint8 ist_pos[2][39];
} drmp3dec_scratch;
static void drmp3_bs_init(drmp3_bs *bs, const drmp3_uint8 *data, int bytes)
{
bs->buf = data;
bs->pos = 0;
bs->limit = bytes*8;
}
static drmp3_uint32 drmp3_bs_get_bits(drmp3_bs *bs, int n)
{
drmp3_uint32 next, cache = 0, s = bs->pos & 7;
int shl = n + s;
const drmp3_uint8 *p = bs->buf + (bs->pos >> 3);
if ((bs->pos += n) > bs->limit)
return 0;
next = *p++ & (255 >> s);
while ((shl -= 8) > 0)
{
cache |= next << shl;
next = *p++;
}
return cache | (next >> -shl);
}
static int drmp3_hdr_valid(const drmp3_uint8 *h)
{
return h[0] == 0xff &&
((h[1] & 0xF0) == 0xf0 || (h[1] & 0xFE) == 0xe2) &&
(DRMP3_HDR_GET_LAYER(h) != 0) &&
(DRMP3_HDR_GET_BITRATE(h) != 15) &&
(DRMP3_HDR_GET_SAMPLE_RATE(h) != 3);
}
static int drmp3_hdr_compare(const drmp3_uint8 *h1, const drmp3_uint8 *h2)
{
return drmp3_hdr_valid(h2) &&
((h1[1] ^ h2[1]) & 0xFE) == 0 &&
((h1[2] ^ h2[2]) & 0x0C) == 0 &&
!(DRMP3_HDR_IS_FREE_FORMAT(h1) ^ DRMP3_HDR_IS_FREE_FORMAT(h2));
}
static unsigned drmp3_hdr_bitrate_kbps(const drmp3_uint8 *h)
{
static const drmp3_uint8 halfrate[2][3][15] = {
{ { 0,4,8,12,16,20,24,28,32,40,48,56,64,72,80 }, { 0,4,8,12,16,20,24,28,32,40,48,56,64,72,80 }, { 0,16,24,28,32,40,48,56,64,72,80,88,96,112,128 } },
{ { 0,16,20,24,28,32,40,48,56,64,80,96,112,128,160 }, { 0,16,24,28,32,40,48,56,64,80,96,112,128,160,192 }, { 0,16,32,48,64,80,96,112,128,144,160,176,192,208,224 } },
};
return 2*halfrate[!!DRMP3_HDR_TEST_MPEG1(h)][DRMP3_HDR_GET_LAYER(h) - 1][DRMP3_HDR_GET_BITRATE(h)];
}
static unsigned drmp3_hdr_sample_rate_hz(const drmp3_uint8 *h)
{
static const unsigned g_hz[3] = { 44100, 48000, 32000 };
return g_hz[DRMP3_HDR_GET_SAMPLE_RATE(h)] >> (int)!DRMP3_HDR_TEST_MPEG1(h) >> (int)!DRMP3_HDR_TEST_NOT_MPEG25(h);
}
static unsigned drmp3_hdr_frame_samples(const drmp3_uint8 *h)
{
return DRMP3_HDR_IS_LAYER_1(h) ? 384 : (1152 >> (int)DRMP3_HDR_IS_FRAME_576(h));
}
static int drmp3_hdr_frame_bytes(const drmp3_uint8 *h, int free_format_size)
{
int frame_bytes = drmp3_hdr_frame_samples(h)*drmp3_hdr_bitrate_kbps(h)*125/drmp3_hdr_sample_rate_hz(h);
if (DRMP3_HDR_IS_LAYER_1(h))
{
frame_bytes &= ~3; /* slot align */
}
return frame_bytes ? frame_bytes : free_format_size;
}
static int drmp3_hdr_padding(const drmp3_uint8 *h)
{
return DRMP3_HDR_TEST_PADDING(h) ? (DRMP3_HDR_IS_LAYER_1(h) ? 4 : 1) : 0;
}
#ifndef DR_MP3_ONLY_MP3
static const drmp3_L12_subband_alloc *drmp3_L12_subband_alloc_table(const drmp3_uint8 *hdr, drmp3_L12_scale_info *sci)
{
const drmp3_L12_subband_alloc *alloc;
int mode = DRMP3_HDR_GET_STEREO_MODE(hdr);
int nbands, stereo_bands = (mode == DRMP3_MODE_MONO) ? 0 : (mode == DRMP3_MODE_JOINT_STEREO) ? (DRMP3_HDR_GET_STEREO_MODE_EXT(hdr) << 2) + 4 : 32;
if (DRMP3_HDR_IS_LAYER_1(hdr))
{
static const drmp3_L12_subband_alloc g_alloc_L1[] = { { 76, 4, 32 } };
alloc = g_alloc_L1;
nbands = 32;
} else if (!DRMP3_HDR_TEST_MPEG1(hdr))
{
static const drmp3_L12_subband_alloc g_alloc_L2M2[] = { { 60, 4, 4 }, { 44, 3, 7 }, { 44, 2, 19 } };
alloc = g_alloc_L2M2;
nbands = 30;
} else
{
static const drmp3_L12_subband_alloc g_alloc_L2M1[] = { { 0, 4, 3 }, { 16, 4, 8 }, { 32, 3, 12 }, { 40, 2, 7 } };
int sample_rate_idx = DRMP3_HDR_GET_SAMPLE_RATE(hdr);
unsigned kbps = drmp3_hdr_bitrate_kbps(hdr) >> (int)(mode != DRMP3_MODE_MONO);
if (!kbps) /* free-format */
{
kbps = 192;
}
alloc = g_alloc_L2M1;
nbands = 27;
if (kbps < 56)
{
static const drmp3_L12_subband_alloc g_alloc_L2M1_lowrate[] = { { 44, 4, 2 }, { 44, 3, 10 } };
alloc = g_alloc_L2M1_lowrate;
nbands = sample_rate_idx == 2 ? 12 : 8;
} else if (kbps >= 96 && sample_rate_idx != 1)
{
nbands = 30;
}
}
sci->total_bands = (drmp3_uint8)nbands;
sci->stereo_bands = (drmp3_uint8)DRMP3_MIN(stereo_bands, nbands);
return alloc;
}
static void drmp3_L12_read_scalefactors(drmp3_bs *bs, drmp3_uint8 *pba, drmp3_uint8 *scfcod, int bands, float *scf)
{
static const float g_deq_L12[18*3] = {
#define DRMP3_DQ(x) 9.53674316e-07f/x, 7.56931807e-07f/x, 6.00777173e-07f/x
DRMP3_DQ(3),DRMP3_DQ(7),DRMP3_DQ(15),DRMP3_DQ(31),DRMP3_DQ(63),DRMP3_DQ(127),DRMP3_DQ(255),DRMP3_DQ(511),DRMP3_DQ(1023),DRMP3_DQ(2047),DRMP3_DQ(4095),DRMP3_DQ(8191),DRMP3_DQ(16383),DRMP3_DQ(32767),DRMP3_DQ(65535),DRMP3_DQ(3),DRMP3_DQ(5),DRMP3_DQ(9)
};
int i, m;
for (i = 0; i < bands; i++)
{
float s = 0;
int ba = *pba++;
int mask = ba ? 4 + ((19 >> scfcod[i]) & 3) : 0;
for (m = 4; m; m >>= 1)
{
if (mask & m)
{
int b = drmp3_bs_get_bits(bs, 6);
s = g_deq_L12[ba*3 - 6 + b % 3]*(int)(1 << 21 >> b/3);
}
*scf++ = s;
}
}
}
static void drmp3_L12_read_scale_info(const drmp3_uint8 *hdr, drmp3_bs *bs, drmp3_L12_scale_info *sci)
{
static const drmp3_uint8 g_bitalloc_code_tab[] = {
0,17, 3, 4, 5,6,7, 8,9,10,11,12,13,14,15,16,
0,17,18, 3,19,4,5, 6,7, 8, 9,10,11,12,13,16,
0,17,18, 3,19,4,5,16,
0,17,18,16,
0,17,18,19, 4,5,6, 7,8, 9,10,11,12,13,14,15,
0,17,18, 3,19,4,5, 6,7, 8, 9,10,11,12,13,14,
0, 2, 3, 4, 5,6,7, 8,9,10,11,12,13,14,15,16
};
const drmp3_L12_subband_alloc *subband_alloc = drmp3_L12_subband_alloc_table(hdr, sci);
int i, k = 0, ba_bits = 0;
const drmp3_uint8 *ba_code_tab = g_bitalloc_code_tab;
for (i = 0; i < sci->total_bands; i++)
{
drmp3_uint8 ba;
if (i == k)
{
k += subband_alloc->band_count;
ba_bits = subband_alloc->code_tab_width;
ba_code_tab = g_bitalloc_code_tab + subband_alloc->tab_offset;
subband_alloc++;
}
ba = ba_code_tab[drmp3_bs_get_bits(bs, ba_bits)];
sci->bitalloc[2*i] = ba;
if (i < sci->stereo_bands)
{
ba = ba_code_tab[drmp3_bs_get_bits(bs, ba_bits)];
}
sci->bitalloc[2*i + 1] = sci->stereo_bands ? ba : 0;
}
for (i = 0; i < 2*sci->total_bands; i++)
{
sci->scfcod[i] = (drmp3_uint8)(sci->bitalloc[i] ? DRMP3_HDR_IS_LAYER_1(hdr) ? 2 : drmp3_bs_get_bits(bs, 2) : 6);
}
drmp3_L12_read_scalefactors(bs, sci->bitalloc, sci->scfcod, sci->total_bands*2, sci->scf);
for (i = sci->stereo_bands; i < sci->total_bands; i++)
{
sci->bitalloc[2*i + 1] = 0;
}
}
static int drmp3_L12_dequantize_granule(float *grbuf, drmp3_bs *bs, drmp3_L12_scale_info *sci, int group_size)
{
int i, j, k, choff = 576;
for (j = 0; j < 4; j++)
{
float *dst = grbuf + group_size*j;
for (i = 0; i < 2*sci->total_bands; i++)
{
int ba = sci->bitalloc[i];
if (ba != 0)
{
if (ba < 17)
{
int half = (1 << (ba - 1)) - 1;
for (k = 0; k < group_size; k++)
{
dst[k] = (float)((int)drmp3_bs_get_bits(bs, ba) - half);
}
} else