Merge "Proper adjustment of filterlength for downsampling" (c6d7ab74) · Commits · e / os / android_frameworks_av

services/audioflinger/AudioResamplerDyn.cpp

+14 −6

Original line number	Diff line number	Diff line
		@@ -283,17 +283,25 @@ void AudioResamplerDyn::setSampleRate(int32_t inSampleRate) {
		// 32b coefficients, 64 length
		useS32 = true;
		stopBandAtten = 98.;
		if (inSampleRate >= mSampleRate * 4) {
		halfLength = 48;
		} else if (inSampleRate >= mSampleRate * 2) {
		halfLength = 40;
		} else {
		halfLength = 32;
		}
		} else if (mFilterQuality == DYN_LOW_QUALITY) {
		// 16b coefficients, 16-32 length
		useS32 = false;
		stopBandAtten = 80.;
		if (mSampleRate >= inSampleRate * 2) {
		if (inSampleRate >= mSampleRate * 4) {
		halfLength = 24;
		} else if (inSampleRate >= mSampleRate * 2) {
		halfLength = 16;
		} else {
		halfLength = 8;
		}
		if (mSampleRate >= inSampleRate) {
		if (inSampleRate <= mSampleRate) {
		tbwCheat = 1.05;
		} else {
		tbwCheat = 1.03;
		@@ -303,14 +311,14 @@ void AudioResamplerDyn::setSampleRate(int32_t inSampleRate) {
		// note: > 64 length filters with 16b coefs can have quantization noise problems
		useS32 = false;
		stopBandAtten = 84.;
		if (mSampleRate >= inSampleRate * 4) {
		if (inSampleRate >= mSampleRate * 4) {
		halfLength = 32;
		} else if (mSampleRate >= inSampleRate * 2) {
		} else if (inSampleRate >= mSampleRate * 2) {
		halfLength = 24;
		} else {
		halfLength = 16;
		}
		if (mSampleRate >= inSampleRate) {
		if (inSampleRate <= mSampleRate) {
		tbwCheat = 1.03;
		} else {
		tbwCheat = 1.01;