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audio: Initial bits to enable audio capture support.

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icculus committed Aug 1, 2016
1 parent 4569011 commit ee099750079ed30326dd6e3be0df32f2d68d474c
Showing with 167 additions and 1 deletion.
  1. +1 −0 .hgignore
  2. +1 −1 src/audio/SDL_audio.c
  3. +4 −0 test/Makefile.in
  4. +161 −0 test/testaudiocapture.c
@@ -120,6 +120,7 @@ test/testbounds
test/torturethread
test/testdisplayinfo
test/testqsort
test/testaudiocapture
test/*.exe
test/*.dSYM
buildbot
@@ -317,7 +317,7 @@ add_audio_device(const char *name, void *handle, SDL_AudioDeviceItem **devices,
static SDL_INLINE int
add_capture_device(const char *name, void *handle)
{
/* !!! FIXME: add this later. SDL_assert(current_audio.impl.HasCaptureSupport);*/
SDL_assert(current_audio.impl.HasCaptureSupport);
return add_audio_device(name, handle, &current_audio.inputDevices, &current_audio.inputDeviceCount);
}

@@ -13,6 +13,7 @@ TARGETS = \
loopwavequeue$(EXE) \
testatomic$(EXE) \
testaudioinfo$(EXE) \
testaudiocapture$(EXE) \
testautomation$(EXE) \
testbounds$(EXE) \
testcustomcursor$(EXE) \
@@ -113,6 +114,9 @@ testmultiaudio$(EXE): $(srcdir)/testmultiaudio.c
testaudiohotplug$(EXE): $(srcdir)/testaudiohotplug.c
$(CC) -o $@ $^ $(CFLAGS) $(LIBS)

testaudiocapture$(EXE): $(srcdir)/testaudiocapture.c
$(CC) -o $@ $^ $(CFLAGS) $(LIBS)

testatomic$(EXE): $(srcdir)/testatomic.c
$(CC) -o $@ $^ $(CFLAGS) $(LIBS)

@@ -0,0 +1,161 @@
/*
Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely.
*/
#include "SDL.h"

#ifdef __EMSCRIPTEN__
#include <emscripten/emscripten.h>
#endif

#define CAPTURE_SECONDS 5

static SDL_AudioSpec spec;
static Uint8 *sound = NULL; /* Pointer to wave data */
static Uint32 soundlen = 0; /* Length of wave data */
static Uint32 processed = 0;
static SDL_AudioDeviceID devid = 0;

void SDLCALL
capture_callback(void *arg, Uint8 * stream, int len)
{
const int avail = (int) (soundlen - processed);
if (len > avail) {
len = avail;
}

/*SDL_Log("CAPTURE CALLBACK: %d more bytes\n", len);*/
SDL_memcpy(sound + processed, stream, len);
processed += len;
}

void SDLCALL
play_callback(void *arg, Uint8 * stream, int len)
{
const Uint8 *waveptr = sound + processed;
const int avail = soundlen - processed;
int cpy = len;
if (cpy > avail) {
cpy = avail;
}

/*SDL_Log("PLAY CALLBACK: %d more bytes\n", cpy);*/
SDL_memcpy(stream, waveptr, cpy);
processed += cpy;

len -= cpy;
if (len > 0) {
SDL_memset(stream + cpy, spec.silence, len);
}
}

static void
loop()
{
SDL_Event e;
SDL_bool please_quit = SDL_FALSE;

while (SDL_PollEvent(&e)) {
if (e.type == SDL_QUIT) {
please_quit = SDL_TRUE;
}
}

if ((!please_quit) && (processed >= soundlen)) {
processed = 0;
if (spec.callback == capture_callback) {
SDL_Log("Done recording, playing back...\n");
SDL_PauseAudioDevice(devid, 1);
SDL_CloseAudioDevice(devid);

spec.callback = play_callback;
devid = SDL_OpenAudioDevice(NULL, 0, &spec, &spec, 0);
if (!devid) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open an audio device for playback!\n");
SDL_Quit();
exit(1);
}

SDL_PauseAudioDevice(devid, 0);
} else {
SDL_Log("Done playing back.\n");
please_quit = SDL_TRUE;
}
}

if (please_quit) {
/* stop playing back, quit. */
SDL_Log("Shutting down.\n");
SDL_PauseAudioDevice(devid, 1);
SDL_CloseAudioDevice(devid);
SDL_free(sound);
sound = NULL;
SDL_Quit();
#ifdef __EMSCRIPTEN__
emscripten_cancel_main_loop();
#endif
exit(0);
}
}

int
main(int argc, char **argv)
{
/* Enable standard application logging */
SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);

/* Load the SDL library */
if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO) < 0) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
return (1);
}

/* Android apparently needs a window...? */
#ifdef __ANDROID__
SDL_CreateWindow("testaudiocapture", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 320, 240, 0);
#endif

SDL_Log("Using audio driver: %s\n", SDL_GetCurrentAudioDriver());

SDL_zero(spec);
spec.freq = 44100;
spec.format = AUDIO_F32SYS;
spec.channels = 1;
spec.samples = 1024;
spec.callback = capture_callback;

soundlen = spec.freq * (SDL_AUDIO_BITSIZE(spec.format) / 8) * spec.channels * CAPTURE_SECONDS;
sound = (Uint8 *) SDL_malloc(soundlen);
if (!sound) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Out of memory\n");
SDL_Quit();
return 1;
}

devid = SDL_OpenAudioDevice(NULL, 1, &spec, &spec, 0);
if (!devid) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open an audio device for capture: %s!\n", SDL_GetError());
SDL_free(sound);
SDL_Quit();
exit(1);
}

SDL_Log("Recording for %d seconds...\n", CAPTURE_SECONDS);
SDL_PauseAudioDevice(devid, 0);

#ifdef __EMSCRIPTEN__
emscripten_set_main_loop(loop, 0, 1);
#else
while (1) { loop(); SDL_Delay(16); }
#endif

return 0;
}

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