static unsigned int get_supported_rate(unsigned int prefered_rate) {
JNIEnv *jni_env = ms_get_jni_env();
jclass audio_record_class = jni_env->FindClass("android/media/AudioRecord");
int size = jni_env->CallStaticIntMethod(audio_record_class
,jni_env->GetStaticMethodID(audio_record_class,"getMinBufferSize", "(III)I")
,prefered_rate
,2/*CHANNEL_CONFIGURATION_MONO*/
,2/* ENCODING_PCM_16BIT */);
if (size > 0) {
return prefered_rate;
} else {
ms_warning("Cannot configure recorder with rate [%i]",prefered_rate);
if (prefered_rate>48000) {
return get_supported_rate(48000);
}
switch (prefered_rate) {
case 12000:
case 24000: return get_supported_rate(48000);
case 48000: return get_supported_rate(44100);
case 44100: return get_supported_rate(16000);
case 16000: return get_supported_rate(8000);
default: {
ms_error("This Android sound card doesn't support any standard sample rate");
return 0;
}
}
return 0;
}
}
/***********************************read filter********************/
static int set_read_rate(MSFilter *f, void *arg){
unsigned int proposed_rate = *((unsigned int*)arg);
ms_debug("set_rate %d",proposed_rate);
msandroid_sound_data *d=(msandroid_sound_data*)f->data;
d->rate=get_supported_rate(proposed_rate);
if (d->rate == proposed_rate)
return 0;
else
return -1;
}
/***********************************read filter********************/
static int set_read_rate(MSFilter *f, void *arg){
unsigned int proposed_rate = *((unsigned int*)arg);
ms_debug("set_rate %d",proposed_rate);
msandroid_sound_data *d=(msandroid_sound_data*)f->data;
if (d->forced_rate) {
ms_warning("sample rate is forced by mediastreamer2 device table, skipping...");
return -1;
}
d->rate=get_supported_rate(proposed_rate);
if (d->rate == proposed_rate)
return 0;
else
return -1;
}