#include #include #include int main(int argc, char *argv[]) { pa_volume_t v; pa_cvolume cv; float b; pa_channel_map map; printf("Attenuation of sample 1 against 32767: %g dB\n", 20.0*log10(1.0/32767.0)); printf("Smallest possible attenutation > 0 applied to 32767: %li\n", lrint(32767.0*pa_sw_volume_to_linear(1))); for (v = PA_VOLUME_MUTED; v <= PA_VOLUME_NORM*2; v += 256) { double dB = pa_sw_volume_to_dB(v); double f = pa_sw_volume_to_linear(v); printf("Volume: %3i; percent: %i%%; decibel %0.2f; linear = %0.2f; volume(decibel): %3i; volume(linear): %3i\n", v, (v*100)/PA_VOLUME_NORM, dB, f, pa_sw_volume_from_dB(dB), pa_sw_volume_from_linear(f)); } for (v = PA_VOLUME_MUTED; v <= PA_VOLUME_NORM*2; v += 256) { char s[PA_CVOLUME_SNPRINT_MAX], t[PA_SW_CVOLUME_SNPRINT_DB_MAX]; pa_cvolume_set(&cv, 2, v); printf("Volume: %3i [%s] [%s]\n", v, pa_cvolume_snprint(s, sizeof(s), &cv), pa_sw_cvolume_snprint_dB(t, sizeof(t), &cv)); } map.channels = cv.channels = 2; map.map[0] = PA_CHANNEL_POSITION_LEFT; map.map[1] = PA_CHANNEL_POSITION_RIGHT; for (cv.values[0] = PA_VOLUME_MUTED; cv.values[0] <= PA_VOLUME_NORM*2; cv.values[0] += 4096) for (cv.values[1] = PA_VOLUME_MUTED; cv.values[1] <= PA_VOLUME_NORM*2; cv.values[1] += 4096) { char s[PA_CVOLUME_SNPRINT_MAX]; printf("Volume: [%s]; balance: %2.1f\n", pa_cvolume_snprint(s, sizeof(s), &cv), pa_cvolume_get_balance(&cv, &map)); } for (cv.values[0] = PA_VOLUME_MUTED+4096; cv.values[0] <= PA_VOLUME_NORM*2; cv.values[0] += 4096) for (cv.values[1] = PA_VOLUME_MUTED; cv.values[1] <= PA_VOLUME_NORM*2; cv.values[1] += 4096) for (b = -1.0f; b <= 1.0f; b += 0.2f) { char s[PA_CVOLUME_SNPRINT_MAX]; pa_cvolume r; float k; printf("Before: volume: [%s]; balance: %2.1f\n", pa_cvolume_snprint(s, sizeof(s), &cv), pa_cvolume_get_balance(&cv, &map)); r = cv; pa_cvolume_set_balance(&r, &map,b); k = pa_cvolume_get_balance(&r, &map); printf("After: volume: [%s]; balance: %2.1f (intended: %2.1f) %s\n", pa_cvolume_snprint(s, sizeof(s), &r), k, b, k < b-.05 || k > b+.5 ? "MISMATCH" : ""); } return 0; }