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GBA Audio: Add blip_buf support

This commit is contained in:
Jeffrey Pfau 2014-12-29 00:48:23 -08:00
parent 93b7779cb2
commit b92ed79a85
10 changed files with 1056 additions and 12 deletions
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1
CHANGES
View File

@ -10,6 +10,7 @@ Features:
- List of recently opened games
- Support for games using the Solar Sensor
- Debugger: Add CLI functions for writing to memory
- Better audio resampling via blip-buf
Bugfixes:
- Qt: Fix issue with set frame sizes being the wrong height
- Qt: Fix emulator crashing when full screen if a game is not running

25
CMakeLists.txt
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@ -8,6 +8,7 @@ set(USE_FFMPEG ON CACHE BOOL "Whether or not to enable FFmpeg support")
set(USE_PNG ON CACHE BOOL "Whether or not to enable PNG support")
set(USE_LIBZIP ON CACHE BOOL "Whether or not to enable ZIP support")
set(USE_MAGICK ON CACHE BOOL "Whether or not to enable ImageMagick support")
set(USE_BLIP ON CACHE BOOL "Whether or not to enable blip_buf support")
set(BUILD_QT ON CACHE BOOL "Build Qt frontend")
set(BUILD_SDL ON CACHE BOOL "Build SDL frontend")
set(BUILD_PERF OFF CACHE BOOL "Build performance profiling tool")
@ -100,6 +101,9 @@ if(HAVE_STRNDUP)
add_definitions(-DHAVE_STRNDUP)
endif()
set(USE_RESAMPLE OFF)
set(RESAMPLE_LIBRARY "None")
# Platform support
if(WIN32)
add_definitions(-D_WIN32_WINNT=0x0600)
@ -157,17 +161,25 @@ if(USE_FFMPEG)
include_directories(AFTER ${LIBAVCODEC_INCLUDE_DIRS} ${LIBAVFORMAT_INCLUDE_DIRS} ${LIBAVRESAMPLE_INCLUDE_DIRS} ${LIBAVUTIL_INCLUDE_DIRS} ${LIBSWSCALE_INCLUDE_DIRS})
link_directories(${LIBAVCODEC_LIBRARY_DIRS} ${LIBAVFORMAT_LIBRARY_DIRS} ${LIBAVRESAMPLE_LIBRARY_DIRS} ${LIBAVUTIL_LIBRARY_DIRS} ${LIBSWSCALE_LIBRARY_DIRS})
list(APPEND UTIL_SRC "${CMAKE_SOURCE_DIR}/src/platform/ffmpeg/ffmpeg-encoder.c")
list(APPEND UTIL_SRC "${CMAKE_SOURCE_DIR}/src/platform/ffmpeg/ffmpeg-resample.c")
set(RESAMPLE_SRC "${CMAKE_SOURCE_DIR}/src/platform/ffmpeg/ffmpeg-resample.c")
string(REGEX MATCH "^[0-9]+" LIBAVCODEC_VERSION_MAJOR ${libavcodec_VERSION})
string(REGEX MATCH "^[0-9]+" LIBAVFORMAT_VERSION_MAJOR ${libavformat_VERSION})
string(REGEX MATCH "^[0-9]+" LIBAVRESAMPLE_VERSION_MAJOR ${libavresample_VERSION})
string(REGEX MATCH "^[0-9]+" LIBAVUTIL_VERSION_MAJOR ${libavutil_VERSION})
string(REGEX MATCH "^[0-9]+" LIBSWSCALE_VERSION_MAJOR ${libswscale_VERSION})
list(APPEND DEPENDENCY_LIB ${LIBAVCODEC_LIBRARIES} ${LIBAVFORMAT_LIBRARIES} ${LIBAVRESAMPLE_LIBRARIES} ${LIBAVUTIL_LIBRARIES} ${LIBSWSCALE_LIBRARIES})
set(RESAMPLE_LIBRARY "FFmpeg")
set(USE_RESAMPLE ON)
set(CPACK_DEBIAN_PACKAGE_DEPENDS "${CPACK_DEBIAN_PACKAGE_DEPENDS},libavcodec${LIBAVCODEC_VERSION_MAJOR},libavformat${LIBAVFORMAT_VERSION_MAJOR},libavresample${LIBAVRESAMPLE_VERSION_MAJOR},libavutil${LIBAVUTIL_VERSION_MAJOR},libswscale${LIBSWSCALE_VERSION_MAJOR}")
set(CPACK_DEBIAN_PACKAGE_RECOMMENDS "libavcodec-extra")
endif()
if(USE_BLIP)
set(RESAMPLE_SRC "${CMAKE_SOURCE_DIR}/src/third-party/blip_buf/blip_buf.c")
set(RESAMPLE_LIBRARY "blip_buf")
set(USE_RESAMPLE ON)
endif()
if(USE_MAGICK)
add_definitions(-DUSE_MAGICK)
include_directories(AFTER ${MAGICKWAND_INCLUDE_DIRS})
@ -198,6 +210,15 @@ if(USE_LIBZIP)
set(CPACK_DEBIAN_PACKAGE_DEPENDS "${CPACK_DEBIAN_PACKAGE_DEPENDS},libzip2")
endif()
if(USE_RESAMPLE)
string(TOUPPER ${RESAMPLE_LIBRARY} RESAMPLE_DEFINE)
set(RESAMPLE_DEFINE "RESAMPLE_${RESAMPLE_DEFINE}")
list(APPEND UTIL_SRC ${RESAMPLE_SRC})
add_definitions(-DRESAMPLE_LIBRARY=${RESAMPLE_DEFINE})
else()
add_definitions(-DRESAMPLE_LIBRARY=RESAMPLE_NN)
endif()
# Binaries
add_library(${BINARY_NAME} SHARED
${ARM_SRC}
@ -257,7 +278,7 @@ message(STATUS " Video recording: ${USE_FFMPEG}")
message(STATUS " GIF recording: ${USE_MAGICK}")
message(STATUS " Screenshot/advanced savestate support: ${USE_PNG}")
message(STATUS " ZIP support: ${USE_LIBZIP}")
message(STATUS " Better audio resampling: ${USE_FFMPEG}")
message(STATUS " Better audio resampling (${RESAMPLE_LIBRARY}): ${USE_RESAMPLE}")
message(STATUS "Frontend summary:")
message(STATUS " Qt: ${BUILD_QT}")
message(STATUS " SDL (${SDL_VERSION}): ${BUILD_SDL}")

59
src/gba/gba-audio.c
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@ -12,6 +12,7 @@
#include "gba-video.h"
const unsigned GBA_AUDIO_SAMPLES = 2048;
const unsigned BLIP_BUFFER_SIZE = 0x4000;
const unsigned GBA_AUDIO_FIFO_SIZE = 8 * sizeof(int32_t);
#define SWEEP_CYCLES (GBA_ARM7TDMI_FREQUENCY / 128)
@ -27,8 +28,17 @@ static int _applyBias(struct GBAAudio* audio, int sample);
static void _sample(struct GBAAudio* audio);
void GBAAudioInit(struct GBAAudio* audio, size_t samples) {
audio->samples = samples;
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
CircleBufferInit(&audio->left, samples * sizeof(int16_t));
CircleBufferInit(&audio->right, samples * sizeof(int16_t));
#else
audio->left = blip_new(BLIP_BUFFER_SIZE);
audio->right = blip_new(BLIP_BUFFER_SIZE);
// Guess too large; we hang producing extra samples if we guess too low
blip_set_rates(audio->left, GBA_ARM7TDMI_FREQUENCY, 96000);
blip_set_rates(audio->right, GBA_ARM7TDMI_FREQUENCY, 96000);
#endif
CircleBufferInit(&audio->chA.fifo, GBA_AUDIO_FIFO_SIZE);
CircleBufferInit(&audio->chB.fifo, GBA_AUDIO_FIFO_SIZE);
}
@ -77,21 +87,34 @@ void GBAAudioReset(struct GBAAudio* audio) {
audio->enable = false;
audio->sampleInterval = GBA_ARM7TDMI_FREQUENCY / audio->sampleRate;
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
CircleBufferClear(&audio->left);
CircleBufferClear(&audio->right);
#else
blip_clear(audio->left);
blip_clear(audio->right);
audio->clock = 0;
#endif
CircleBufferClear(&audio->chA.fifo);
CircleBufferClear(&audio->chB.fifo);
}
void GBAAudioDeinit(struct GBAAudio* audio) {
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
CircleBufferDeinit(&audio->left);
CircleBufferDeinit(&audio->right);
#else
blip_delete(audio->left);
blip_delete(audio->right);
#endif
CircleBufferDeinit(&audio->chA.fifo);
CircleBufferDeinit(&audio->chB.fifo);
}
void GBAAudioResizeBuffer(struct GBAAudio* audio, size_t samples) {
GBASyncLockAudio(audio->p->sync);
audio->samples = samples;
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
size_t oldCapacity = audio->left.capacity;
int16_t* buffer = malloc(oldCapacity);
int16_t dummy;
@ -119,6 +142,11 @@ void GBAAudioResizeBuffer(struct GBAAudio* audio, size_t samples) {
}
free(buffer);
#else
blip_clear(audio->left);
blip_clear(audio->right);
audio->clock = 0;
#endif
GBASyncConsumeAudio(audio->p->sync);
}
@ -424,6 +452,13 @@ void GBAAudioWriteSOUNDCNT_X(struct GBAAudio* audio, uint16_t value) {
void GBAAudioWriteSOUNDBIAS(struct GBAAudio* audio, uint16_t value) {
audio->soundbias = value;
#if RESAMPLE_LIBRARY == RESAMPLE_BLIP_BUF
unsigned newSampleRate = 0x8000 << GBARegisterSOUNDBIASGetResolution(audio->soundbias);
if (audio->sampleRate != newSampleRate) {
audio->sampleRate = newSampleRate;
audio->sampleInterval = GBA_ARM7TDMI_FREQUENCY / audio->sampleRate;
}
#endif
}
void GBAAudioWriteWaveRAM(struct GBAAudio* audio, int address, uint32_t value) {
@ -495,6 +530,7 @@ void GBAAudioSampleFIFO(struct GBAAudio* audio, int fifoId, int32_t cycles) {
CircleBufferRead8(&channel->fifo, &channel->sample);
}
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
unsigned GBAAudioCopy(struct GBAAudio* audio, void* left, void* right, unsigned nSamples) {
GBASyncLockAudio(audio->p->sync);
unsigned read = 0;
@ -553,6 +589,7 @@ unsigned GBAAudioResampleNN(struct GBAAudio* audio, float ratio, float* drift, s
}
return totalRead;
}
#endif
bool _writeEnvelope(struct GBAAudioEnvelope* envelope, uint16_t value) {
envelope->length = GBAAudioRegisterEnvelopeGetLength(value);
@ -771,14 +808,32 @@ static void _sample(struct GBAAudio* audio) {
sampleRight = _applyBias(audio, sampleRight);
GBASyncLockAudio(audio->p->sync);
unsigned produced;
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
CircleBufferWrite16(&audio->left, sampleLeft);
CircleBufferWrite16(&audio->right, sampleRight);
unsigned produced = CircleBufferSize(&audio->left);
produced = CircleBufferSize(&audio->left) / 2;
#else
if ((size_t) blip_samples_avail(audio->left) < audio->samples) {
blip_add_delta(audio->left, audio->clock, sampleLeft - audio->lastLeft);
blip_add_delta(audio->right, audio->clock, sampleRight - audio->lastRight);
audio->lastLeft = sampleLeft;
audio->lastRight = sampleRight;
audio->clock += audio->sampleInterval;
int clockNeeded = blip_clocks_needed(audio->left, audio->samples / 32);
if (audio->clock >= clockNeeded) {
blip_end_frame(audio->left, audio->clock);
blip_end_frame(audio->right, audio->clock);
audio->clock -= clockNeeded;
}
}
produced = blip_samples_avail(audio->left);
#endif
struct GBAThread* thread = GBAThreadGetContext();
if (thread && thread->stream) {
thread->stream->postAudioFrame(thread->stream, sampleLeft, sampleRight);
}
GBASyncProduceAudio(audio->p->sync, produced >= CircleBufferCapacity(&audio->left));
GBASyncProduceAudio(audio->p->sync, produced >= audio->samples);
}
void GBAAudioSerialize(const struct GBAAudio* audio, struct GBASerializedState* state) {

19
src/gba/gba-audio.h
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@ -11,10 +11,18 @@
#include "util/circle-buffer.h"
#if RESAMPLE_LIBRARY == RESAMPLE_BLIP_BUF
#include "third-party/blip_buf/blip_buf.h"
#endif
struct GBADMA;
extern const unsigned GBA_AUDIO_SAMPLES;
#define RESAMPLE_NN 0
#define RESAMPLE_FFMPEG 1
#define RESAMPLE_BLIP_BUF 2
DECL_BITFIELD(GBAAudioRegisterEnvelope, uint16_t);
DECL_BITS(GBAAudioRegisterEnvelope, Length, 0, 6);
DECL_BITS(GBAAudioRegisterEnvelope, Duty, 6, 2);
@ -177,8 +185,16 @@ struct GBAAudio {
struct GBAAudioFIFO chA;
struct GBAAudioFIFO chB;
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
struct CircleBuffer left;
struct CircleBuffer right;
#else
blip_t* left;
blip_t* right;
int16_t lastLeft;
int16_t lastRight;
int clock;
#endif
uint8_t volumeRight;
uint8_t volumeLeft;
@ -207,6 +223,7 @@ struct GBAAudio {
bool playingCh4;
bool enable;
size_t samples;
unsigned sampleRate;
GBARegisterSOUNDBIAS soundbias;
@ -256,8 +273,10 @@ void GBAAudioWriteFIFO16(struct GBAAudio* audio, int address, uint16_t value);
void GBAAudioWriteFIFO(struct GBAAudio* audio, int address, uint32_t value);
void GBAAudioSampleFIFO(struct GBAAudio* audio, int fifoId, int32_t cycles);
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
unsigned GBAAudioCopy(struct GBAAudio* audio, void* left, void* right, unsigned nSamples);
unsigned GBAAudioResampleNN(struct GBAAudio*, float ratio, float* drift, struct GBAStereoSample* output, unsigned nSamples);
#endif
struct GBASerializedState;
void GBAAudioSerialize(const struct GBAAudio* audio, struct GBASerializedState* state);

4
src/platform/qt/GameController.cpp
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@ -369,6 +369,7 @@ void GameController::updateKeys() {
}
void GameController::redoSamples(int samples) {
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
float sampleRate = 0x8000;
float ratio;
if (m_threadContext.gba) {
@ -376,6 +377,9 @@ void GameController::redoSamples(int samples) {
}
ratio = GBAAudioCalculateRatio(sampleRate, m_threadContext.fpsTarget, 44100);
m_threadContext.audioBuffers = ceil(samples / ratio);
#else
m_threadContext.audioBuffers = samples;
#endif
if (m_threadContext.gba) {
GBAAudioResizeBuffer(&m_threadContext.gba->audio, m_threadContext.audioBuffers);
}

32
src/platform/sdl/sdl-audio.c
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@ -8,9 +8,11 @@
#include "gba.h"
#include "gba-thread.h"
#ifdef USE_FFMPEG
#if RESAMPLE_LIBRARY == RESAMPLE_FFMPEG
#include "platform/ffmpeg/ffmpeg-resample.h"
#include <libavresample/avresample.h>
#elif RESAMPLE_LIBRARY == RESAMPLE_BLIP_BUF
#include "third-party/blip_buf/blip_buf.h"
#endif
#define BUFFER_SIZE (GBA_AUDIO_SAMPLES >> 2)
@ -29,7 +31,7 @@ bool GBASDLInitAudio(struct GBASDLAudio* context, struct GBAThread* threadContex
context->desiredSpec.samples = context->samples;
context->desiredSpec.callback = _GBASDLAudioCallback;
context->desiredSpec.userdata = context;
#ifndef USE_FFMPEG
#if RESAMPLE_LIBRARY == RESAMPLE_NN
context->drift = 0.f;
#endif
if (SDL_OpenAudio(&context->desiredSpec, &context->obtainedSpec) < 0) {
@ -44,7 +46,7 @@ bool GBASDLInitAudio(struct GBASDLAudio* context, struct GBAThread* threadContex
threadContext->audioBuffers = context->samples * 2;
}
#ifdef USE_FFMPEG
#if RESAMPLE_LIBRARY == RESAMPLE_FFMPEG
context->avr = 0;
#endif
@ -57,7 +59,7 @@ void GBASDLDeinitAudio(struct GBASDLAudio* context) {
SDL_PauseAudio(1);
SDL_CloseAudio();
SDL_QuitSubSystem(SDL_INIT_AUDIO);
#ifdef USE_FFMPEG
#if RESAMPLE_LIBRARY == RESAMPLE_FFMPEG
avresample_free(&context->avr);
#endif
}
@ -78,7 +80,7 @@ static void _GBASDLAudioCallback(void* context, Uint8* data, int len) {
memset(data, 0, len);
return;
}
#ifndef USE_FFMPEG
#if RESAMPLE_LIBRARY == RESAMPLE_NN
audioContext->ratio = GBAAudioCalculateRatio(audioContext->thread->gba->audio.sampleRate, audioContext->thread->fpsTarget, audioContext->obtainedSpec.freq);
if (audioContext->ratio == INFINITY) {
memset(data, 0, len);
@ -89,7 +91,7 @@ static void _GBASDLAudioCallback(void* context, Uint8* data, int len) {
if (audioContext->obtainedSpec.channels == 2) {
GBAAudioResampleNN(&audioContext->thread->gba->audio, audioContext->ratio, &audioContext->drift, ssamples, len);
}
#else
#elif RESAMPLE_LIBRARY == RESAMPLE_FFMPEG
float ratio = GBAAudioCalculateRatio(audioContext->thread->gba->audio.sampleRate, audioContext->thread->fpsTarget, audioContext->thread->gba->audio.sampleRate);
if (!audioContext->avr) {
if (!audioContext->thread->gba->audio.sampleRate) {
@ -105,5 +107,23 @@ static void _GBASDLAudioCallback(void* context, Uint8* data, int len) {
struct GBAStereoSample* ssamples = (struct GBAStereoSample*) data;
len /= 2 * audioContext->obtainedSpec.channels;
GBAAudioResampleLAVR(&audioContext->thread->gba->audio, audioContext->avr, ssamples, len);
#elif RESAMPLE_LIBRARY == RESAMPLE_BLIP_BUF
double fauxClock = GBAAudioCalculateRatio(1, audioContext->thread->fpsTarget, 1);
GBASyncLockAudio(&audioContext->thread->sync);
blip_set_rates(audioContext->thread->gba->audio.left, GBA_ARM7TDMI_FREQUENCY, audioContext->obtainedSpec.freq * fauxClock);
blip_set_rates(audioContext->thread->gba->audio.right, GBA_ARM7TDMI_FREQUENCY, audioContext->obtainedSpec.freq * fauxClock);
len /= 2 * audioContext->obtainedSpec.channels;
int available = blip_samples_avail(audioContext->thread->gba->audio.left);
if (available > len) {
available = len;
}
blip_read_samples(audioContext->thread->gba->audio.left, (short*) data, available, audioContext->obtainedSpec.channels == 2);
if (audioContext->obtainedSpec.channels == 2) {
blip_read_samples(audioContext->thread->gba->audio.right, ((short*) data) + 1, available, 1);
}
GBASyncConsumeAudio(&audioContext->thread->sync);
if (available < len) {
memset(((short*) data) + audioContext->obtainedSpec.channels * available, 0, len - available);
}
#endif
}

8
src/platform/sdl/sdl-audio.h
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@ -10,6 +10,8 @@
#include <SDL.h>
#include "gba-audio.h"
struct GBASDLAudio {
// Input
size_t samples;
@ -17,10 +19,12 @@ struct GBASDLAudio {
// State
SDL_AudioSpec desiredSpec;
SDL_AudioSpec obtainedSpec;
#if RESAMPLE_LIBRARY != RESAMPLE_BLIP_BUF
float ratio;
#ifndef USE_FFMPEG
#endif
#if RESAMPLE_LIBRARY == RESAMPLE_NN
float drift;
#else
#elif RESAMPLE_LIBRARY == RESAMPLE_FFMPEG
struct AVAudioResampleContext* avr;
#endif

344
src/third-party/blip_buf/blip_buf.c vendored Normal file
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@ -0,0 +1,344 @@
/* blip_buf 1.1.0. http://www.slack.net/~ant/ */
#include "blip_buf.h"
#include <assert.h>
#include <limits.h>
#include <string.h>
#include <stdlib.h>
/* Library Copyright (C) 2003-2009 Shay Green. This library is free software;
you can redistribute it and/or modify it under the terms of the GNU Lesser
General Public License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version. This
library is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
details. You should have received a copy of the GNU Lesser General Public
License along with this module; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
#if defined (BLARGG_TEST) && BLARGG_TEST
#include "blargg_test.h"
#endif
/* Equivalent to ULONG_MAX >= 0xFFFFFFFF00000000.
Avoids constants that don't fit in 32 bits. */
#if ULONG_MAX/0xFFFFFFFF > 0xFFFFFFFF
typedef unsigned long fixed_t;
enum { pre_shift = 32 };
#elif defined(ULLONG_MAX)
typedef unsigned long long fixed_t;
enum { pre_shift = 32 };
#else
typedef unsigned fixed_t;
enum { pre_shift = 0 };
#endif
enum { time_bits = pre_shift + 20 };
static fixed_t const time_unit = (fixed_t) 1 << time_bits;
enum { bass_shift = 9 }; /* affects high-pass filter breakpoint frequency */
enum { end_frame_extra = 2 }; /* allows deltas slightly after frame length */
enum { half_width = 8 };
enum { buf_extra = half_width*2 + end_frame_extra };
enum { phase_bits = 5 };
enum { phase_count = 1 << phase_bits };
enum { delta_bits = 15 };
enum { delta_unit = 1 << delta_bits };
enum { frac_bits = time_bits - pre_shift };
/* We could eliminate avail and encode whole samples in offset, but that would
limit the total buffered samples to blip_max_frame. That could only be
increased by decreasing time_bits, which would reduce resample ratio accuracy.
*/
/** Sample buffer that resamples to output rate and accumulates samples
until they're read out */
struct blip_t
{
fixed_t factor;
fixed_t offset;
int avail;
int size;
int integrator;
};
typedef int buf_t;
/* probably not totally portable */
#define SAMPLES( buf ) ((buf_t*) ((buf) + 1))
/* Arithmetic (sign-preserving) right shift */
#define ARITH_SHIFT( n, shift ) \
((n) >> (shift))
enum { max_sample = +32767 };
enum { min_sample = -32768 };
#define CLAMP( n ) \
{\
if ( (short) n != n )\
n = ARITH_SHIFT( n, 16 ) ^ max_sample;\
}
static void check_assumptions( void )
{
int n;
#if INT_MAX < 0x7FFFFFFF || UINT_MAX < 0xFFFFFFFF
#error "int must be at least 32 bits"
#endif
assert( (-3 >> 1) == -2 ); /* right shift must preserve sign */
n = max_sample * 2;
CLAMP( n );
assert( n == max_sample );
n = min_sample * 2;
CLAMP( n );
assert( n == min_sample );
assert( blip_max_ratio <= time_unit );
assert( blip_max_frame <= (fixed_t) -1 >> time_bits );
}
blip_t* blip_new( int size )
{
blip_t* m;
assert( size >= 0 );
m = (blip_t*) malloc( sizeof *m + (size + buf_extra) * sizeof (buf_t) );
if ( m )
{
m->factor = time_unit / blip_max_ratio;
m->size = size;
blip_clear( m );
check_assumptions();
}
return m;
}
void blip_delete( blip_t* m )
{
if ( m != NULL )
{
/* Clear fields in case user tries to use after freeing */
memset( m, 0, sizeof *m );
free( m );
}
}
void blip_set_rates( blip_t* m, double clock_rate, double sample_rate )
{
double factor = time_unit * sample_rate / clock_rate;
m->factor = (fixed_t) factor;
/* Fails if clock_rate exceeds maximum, relative to sample_rate */
assert( 0 <= factor - m->factor && factor - m->factor < 1 );
/* Avoid requiring math.h. Equivalent to
m->factor = (int) ceil( factor ) */
if ( m->factor < factor )
m->factor++;
/* At this point, factor is most likely rounded up, but could still
have been rounded down in the floating-point calculation. */
}
void blip_clear( blip_t* m )
{
/* We could set offset to 0, factor/2, or factor-1. 0 is suitable if
factor is rounded up. factor-1 is suitable if factor is rounded down.
Since we don't know rounding direction, factor/2 accommodates either,
with the slight loss of showing an error in half the time. Since for
a 64-bit factor this is years, the halving isn't a problem. */
m->offset = m->factor / 2;
m->avail = 0;
m->integrator = 0;
memset( SAMPLES( m ), 0, (m->size + buf_extra) * sizeof (buf_t) );
}
int blip_clocks_needed( const blip_t* m, int samples )
{
fixed_t needed;
/* Fails if buffer can't hold that many more samples */
assert( samples >= 0 && m->avail + samples <= m->size );
needed = (fixed_t) samples * time_unit;
if ( needed < m->offset )
return 0;
return (needed - m->offset + m->factor - 1) / m->factor;
}
void blip_end_frame( blip_t* m, unsigned t )
{
fixed_t off = t * m->factor + m->offset;
m->avail += off >> time_bits;
m->offset = off & (time_unit - 1);
/* Fails if buffer size was exceeded */
assert( m->avail <= m->size );
}
int blip_samples_avail( const blip_t* m )
{
return m->avail;
}
static void remove_samples( blip_t* m, int count )
{
buf_t* buf = SAMPLES( m );
int remain = m->avail + buf_extra - count;
m->avail -= count;
memmove( &buf [0], &buf [count], remain * sizeof buf [0] );
memset( &buf [remain], 0, count * sizeof buf [0] );
}
int blip_read_samples( blip_t* m, short out [], int count, int stereo )
{
assert( count >= 0 );
if ( count > m->avail )
count = m->avail;
if ( count )
{
int const step = stereo ? 2 : 1;
buf_t const* in = SAMPLES( m );
buf_t const* end = in + count;
int sum = m->integrator;
do
{
/* Eliminate fraction */
int s = ARITH_SHIFT( sum, delta_bits );
sum += *in++;
CLAMP( s );
*out = s;
out += step;
/* High-pass filter */
sum -= s << (delta_bits - bass_shift);
}
while ( in != end );
m->integrator = sum;
remove_samples( m, count );
}
return count;
}
/* Things that didn't help performance on x86:
__attribute__((aligned(128)))
#define short int
restrict
*/
/* Sinc_Generator( 0.9, 0.55, 4.5 ) */
static short const bl_step [phase_count + 1] [half_width] =
{
{ 43, -115, 350, -488, 1136, -914, 5861,21022},
{ 44, -118, 348, -473, 1076, -799, 5274,21001},
{ 45, -121, 344, -454, 1011, -677, 4706,20936},
{ 46, -122, 336, -431, 942, -549, 4156,20829},
{ 47, -123, 327, -404, 868, -418, 3629,20679},
{ 47, -122, 316, -375, 792, -285, 3124,20488},
{ 47, -120, 303, -344, 714, -151, 2644,20256},
{ 46, -117, 289, -310, 634, -17, 2188,19985},
{ 46, -114, 273, -275, 553, 117, 1758,19675},
{ 44, -108, 255, -237, 471, 247, 1356,19327},
{ 43, -103, 237, -199, 390, 373, 981,18944},
{ 42, -98, 218, -160, 310, 495, 633,18527},
{ 40, -91, 198, -121, 231, 611, 314,18078},
{ 38, -84, 178, -81, 153, 722, 22,17599},
{ 36, -76, 157, -43, 80, 824, -241,17092},
{ 34, -68, 135, -3, 8, 919, -476,16558},
{ 32, -61, 115, 34, -60, 1006, -683,16001},
{ 29, -52, 94, 70, -123, 1083, -862,15422},
{ 27, -44, 73, 106, -184, 1152,-1015,14824},
{ 25, -36, 53, 139, -239, 1211,-1142,14210},
{ 22, -27, 34, 170, -290, 1261,-1244,13582},
{ 20, -20, 16, 199, -335, 1301,-1322,12942},
{ 18, -12, -3, 226, -375, 1331,-1376,12293},
{ 15, -4, -19, 250, -410, 1351,-1408,11638},
{ 13, 3, -35, 272, -439, 1361,-1419,10979},
{ 11, 9, -49, 292, -464, 1362,-1410,10319},
{ 9, 16, -63, 309, -483, 1354,-1383, 9660},
{ 7, 22, -75, 322, -496, 1337,-1339, 9005},
{ 6, 26, -85, 333, -504, 1312,-1280, 8355},
{ 4, 31, -94, 341, -507, 1278,-1205, 7713},
{ 3, 35, -102, 347, -506, 1238,-1119, 7082},
{ 1, 40, -110, 350, -499, 1190,-1021, 6464},
{ 0, 43, -115, 350, -488, 1136, -914, 5861}
};
/* Shifting by pre_shift allows calculation using unsigned int rather than
possibly-wider fixed_t. On 32-bit platforms, this is likely more efficient.
And by having pre_shift 32, a 32-bit platform can easily do the shift by
simply ignoring the low half. */
void blip_add_delta( blip_t* m, unsigned time, int delta )
{
unsigned fixed = (unsigned) ((time * m->factor + m->offset) >> pre_shift);
buf_t* out = SAMPLES( m ) + m->avail + (fixed >> frac_bits);
int const phase_shift = frac_bits - phase_bits;
int phase = fixed >> phase_shift & (phase_count - 1);
short const* in = bl_step [phase];
short const* rev = bl_step [phase_count - phase];
int interp = fixed >> (phase_shift - delta_bits) & (delta_unit - 1);
int delta2 = (delta * interp) >> delta_bits;
delta -= delta2;
/* Fails if buffer size was exceeded */
assert( out <= &SAMPLES( m ) [m->size + end_frame_extra] );
out [0] += in[0]*delta + in[half_width+0]*delta2;
out [1] += in[1]*delta + in[half_width+1]*delta2;
out [2] += in[2]*delta + in[half_width+2]*delta2;
out [3] += in[3]*delta + in[half_width+3]*delta2;
out [4] += in[4]*delta + in[half_width+4]*delta2;
out [5] += in[5]*delta + in[half_width+5]*delta2;
out [6] += in[6]*delta + in[half_width+6]*delta2;
out [7] += in[7]*delta + in[half_width+7]*delta2;
in = rev;
out [ 8] += in[7]*delta + in[7-half_width]*delta2;
out [ 9] += in[6]*delta + in[6-half_width]*delta2;
out [10] += in[5]*delta + in[5-half_width]*delta2;
out [11] += in[4]*delta + in[4-half_width]*delta2;
out [12] += in[3]*delta + in[3-half_width]*delta2;
out [13] += in[2]*delta + in[2-half_width]*delta2;
out [14] += in[1]*delta + in[1-half_width]*delta2;
out [15] += in[0]*delta + in[0-half_width]*delta2;
}
void blip_add_delta_fast( blip_t* m, unsigned time, int delta )
{
unsigned fixed = (unsigned) ((time * m->factor + m->offset) >> pre_shift);
buf_t* out = SAMPLES( m ) + m->avail + (fixed >> frac_bits);
int interp = fixed >> (frac_bits - delta_bits) & (delta_unit - 1);
int delta2 = delta * interp;
/* Fails if buffer size was exceeded */
assert( out <= &SAMPLES( m ) [m->size + end_frame_extra] );
out [7] += delta * delta_unit - delta2;
out [8] += delta2;
}

72
src/third-party/blip_buf/blip_buf.h vendored Normal file
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/** \file
Sample buffer that resamples from input clock rate to output sample rate */
/* blip_buf 1.1.0 */
#ifndef BLIP_BUF_H
#define BLIP_BUF_H
#ifdef __cplusplus
extern "C" {
#endif
/** First parameter of most functions is blip_t*, or const blip_t* if nothing
is changed. */
typedef struct blip_t blip_t;
/** Creates new buffer that can hold at most sample_count samples. Sets rates
so that there are blip_max_ratio clocks per sample. Returns pointer to new
buffer, or NULL if insufficient memory. */
blip_t* blip_new( int sample_count );
/** Sets approximate input clock rate and output sample rate. For every
clock_rate input clocks, approximately sample_rate samples are generated. */
void blip_set_rates( blip_t*, double clock_rate, double sample_rate );
enum { /** Maximum clock_rate/sample_rate ratio. For a given sample_rate,
clock_rate must not be greater than sample_rate*blip_max_ratio. */
blip_max_ratio = 1 << 20 };
/** Clears entire buffer. Afterwards, blip_samples_avail() == 0. */
void blip_clear( blip_t* );
/** Adds positive/negative delta into buffer at specified clock time. */
void blip_add_delta( blip_t*, unsigned int clock_time, int delta );
/** Same as blip_add_delta(), but uses faster, lower-quality synthesis. */
void blip_add_delta_fast( blip_t*, unsigned int clock_time, int delta );
/** Length of time frame, in clocks, needed to make sample_count additional
samples available. */
int blip_clocks_needed( const blip_t*, int sample_count );
enum { /** Maximum number of samples that can be generated from one time frame. */
blip_max_frame = 4000 };
/** Makes input clocks before clock_duration available for reading as output
samples. Also begins new time frame at clock_duration, so that clock time 0 in
the new time frame specifies the same clock as clock_duration in the old time
frame specified. Deltas can have been added slightly past clock_duration (up to
however many clocks there are in two output samples). */
void blip_end_frame( blip_t*, unsigned int clock_duration );
/** Number of buffered samples available for reading. */
int blip_samples_avail( const blip_t* );
/** Reads and removes at most 'count' samples and writes them to 'out'. If
'stereo' is true, writes output to every other element of 'out', allowing easy
interleaving of two buffers into a stereo sample stream. Outputs 16-bit signed
samples. Returns number of samples actually read. */
int blip_read_samples( blip_t*, short out [], int count, int stereo );
/** Frees buffer. No effect if NULL is passed. */
void blip_delete( blip_t* );
/* Deprecated */
typedef blip_t blip_buffer_t;
#ifdef __cplusplus
}
#endif
#endif

504
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END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Libraries
If you develop a new library, and you want it to be of the greatest
possible use to the public, we recommend making it free software that
everyone can redistribute and change. You can do so by permitting
redistribution under these terms (or, alternatively, under the terms of the
ordinary General Public License).
To apply these terms, attach the following notices to the library. It is
safest to attach them to the start of each source file to most effectively
convey the exclusion of warranty; and each file should have at least the
"copyright" line and a pointer to where the full notice is found.
<one line to give the library's name and a brief idea of what it does.>
Copyright (C) <year> <name of author>
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
Also add information on how to contact you by electronic and paper mail.
You should also get your employer (if you work as a programmer) or your
school, if any, to sign a "copyright disclaimer" for the library, if
necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright interest in the
library `Frob' (a library for tweaking knobs) written by James Random Hacker.
<signature of Ty Coon>, 1 April 1990
Ty Coon, President of Vice
That's all there is to it!