static int try_format(struct wasapi_state *state,
struct ao *const ao,
int bits, int samplerate,
const struct mp_chmap channels)
{
WAVEFORMATEXTENSIBLE wformat;
set_format(&wformat, bits / 8, samplerate, channels.num, mp_chmap_to_waveext(&channels));
int af_format = format_set_bits(ao->format, bits, bits == 32);
EnterCriticalSection(&state->print_lock);
mp_msg(MSGT_AO, MSGL_V, "ao-wasapi: trying %dch %s @ %dhz\n",
channels.num, af_fmt_to_str(af_format), samplerate);
LeaveCriticalSection(&state->print_lock);
union WAVEFMT u;
u.extensible = &wformat;
WAVEFORMATEX *closestMatch;
HRESULT hr = IAudioClient_IsFormatSupported(state->pAudioClient,
state->share_mode,
u.ex, &closestMatch);
if (closestMatch) {
if (closestMatch->wFormatTag == WAVE_FORMAT_EXTENSIBLE) {
u.ex = closestMatch;
wformat = *u.extensible;
} else {
wformat.Format = *closestMatch;
}
CoTaskMemFree(closestMatch);
}
if (hr == S_FALSE) {
if (set_ao_format(state, ao, wformat)) {
EnterCriticalSection(&state->print_lock);
mp_msg(MSGT_AO, MSGL_V, "ao-wasapi: accepted as %dch %s @ %dhz\n",
ao->channels.num, af_fmt_to_str(ao->format), ao->samplerate);
LeaveCriticalSection(&state->print_lock);
return 1;
}
} if (hr == S_OK || (!state->opt_exclusive && hr == AUDCLNT_E_UNSUPPORTED_FORMAT)) {
// AUDCLNT_E_UNSUPPORTED_FORMAT here means "works in shared, doesn't in exclusive"
if (set_ao_format(state, ao, wformat)) {
EnterCriticalSection(&state->print_lock);
mp_msg(MSGT_AO, MSGL_V, "ao-wasapi: %dch %s @ %dhz accepted\n",
ao->channels.num, af_fmt_to_str(af_format), samplerate);
LeaveCriticalSection(&state->print_lock);
return 1;
}
}
return 0;
}
static int set_ao_format(struct wasapi_state *state,
struct ao *const ao,
WAVEFORMATEXTENSIBLE wformat) {
// .Data1 == 1 is PCM, .Data1 == 3 is IEEE_FLOAT
int format = format_set_bits(ao->format,
wformat.Format.wBitsPerSample, wformat.SubFormat.Data1 == 3);
if (wformat.SubFormat.Data1 != 1 && wformat.SubFormat.Data1 != 3) {
MP_ERR(ao, "unknown SubFormat %"PRIu32"\n",
(uint32_t)wformat.SubFormat.Data1);
return 0;
}
ao->samplerate = wformat.Format.nSamplesPerSec;
ao->bps = wformat.Format.nAvgBytesPerSec;
ao->format = format;
if (ao->channels.num != wformat.Format.nChannels) {
mp_chmap_from_channels(&ao->channels, wformat.Format.nChannels);
}
state->format = wformat;
return 1;
}