From 7047d9e5acf97c91a523c99ccc4b008a35a3e094 Mon Sep 17 00:00:00 2001 From: Darren Salt Date: Wed, 15 Aug 2007 13:42:38 +0100 Subject: Fix an audio resampling problem which was causing regular clicking. The cause was that the resampling code was using only the samples in the buffer but not really handling the transition between two buffers (which it would handle completely independently). The new code remembers the last sample from the previous buffer and uses it in the resampling. We therefore end up one sample behind and without the clicks. --- src/xine-engine/resample.c | 115 +++++++++++++++++++++++++++++---------------- 1 file changed, 74 insertions(+), 41 deletions(-) (limited to 'src/xine-engine/resample.c') diff --git a/src/xine-engine/resample.c b/src/xine-engine/resample.c index a7b16917c..1bc9dfaf9 100644 --- a/src/xine-engine/resample.c +++ b/src/xine-engine/resample.c @@ -24,26 +24,34 @@ #include "config.h" #endif +#include #include #include "attributes.h" #include "resample.h" /* contributed by paul flinders */ -void _x_audio_out_resample_mono(int16_t* input_samples, uint32_t in_samples, +void _x_audio_out_resample_mono(int16_t *last_sample, + int16_t* input_samples, uint32_t in_samples, int16_t* output_samples, uint32_t out_samples) { unsigned int osample; /* 16+16 fixed point math */ - uint32_t isample = 0; - uint32_t istep = ((in_samples-2) << 16)/(out_samples-2); + uint32_t isample = 0xFFFF0000U; + uint32_t istep = (in_samples << 16) / out_samples + 1; #ifdef VERBOSE printf ("Audio : resample %d samples to %d\n", in_samples, out_samples); #endif - for (osample = 0; osample < out_samples - 1; osample++) { + for (osample = 0; osample < out_samples && isample >= 0xFFFF0000U; osample++) { + uint32_t t = isample&0xffff; + output_samples[osample] = (last_sample[0] * (0x10000-t) + input_samples[0] * t) >> 16; + isample += istep; + } + + for (; osample < out_samples; osample++) { int s1; int s2; int16_t os; @@ -58,23 +66,31 @@ void _x_audio_out_resample_mono(int16_t* input_samples, uint32_t in_samples, isample += istep; } - output_samples[out_samples-1] = input_samples[in_samples-1]; + last_sample[0] = input_samples[in_samples - 1]; } -void _x_audio_out_resample_stereo(int16_t* input_samples, uint32_t in_samples, +void _x_audio_out_resample_stereo(int16_t *last_sample, + int16_t* input_samples, uint32_t in_samples, int16_t* output_samples, uint32_t out_samples) { unsigned int osample; /* 16+16 fixed point math */ - uint32_t isample = 0; - uint32_t istep = ((in_samples-2) << 16)/(out_samples-2); + uint32_t isample = 0xFFFF0000U; + uint32_t istep = (in_samples << 16) / out_samples + 1; #ifdef VERBOSE printf ("Audio : resample %d samples to %d\n", in_samples, out_samples); #endif - for (osample = 0; osample < out_samples - 1; osample++) { + for (osample = 0; osample < out_samples && isample >= 0xFFFF0000U; osample++) { + uint32_t t = isample&0xffff; + output_samples[osample*2 ] = (last_sample[0] * (0x10000-t) + input_samples[0] * t) >> 16; + output_samples[osample*2+1] = (last_sample[1] * (0x10000-t) + input_samples[1] * t) >> 16; + isample += istep; + } + + for (; osample < out_samples; osample++) { int s1; int s2; int16_t os; @@ -94,25 +110,34 @@ void _x_audio_out_resample_stereo(int16_t* input_samples, uint32_t in_samples, output_samples[(osample * 2 )+1] = os; isample += istep; } - output_samples[out_samples*2-2] = input_samples[in_samples*2-2]; - output_samples[out_samples*2-1] = input_samples[in_samples*2-1]; + memcpy (last_sample, &input_samples[in_samples*2-2], 2 * sizeof (last_sample[0])); } -void _x_audio_out_resample_4channel(int16_t* input_samples, uint32_t in_samples, +void _x_audio_out_resample_4channel(int16_t *last_sample, + int16_t* input_samples, uint32_t in_samples, int16_t* output_samples, uint32_t out_samples) { unsigned int osample; /* 16+16 fixed point math */ - uint32_t isample = 0; - uint32_t istep = ((in_samples-2) << 16)/(out_samples-2); + uint32_t isample = 0xFFFF0000U; + uint32_t istep = (in_samples << 16) / out_samples + 1; #ifdef VERBOSE printf ("Audio : resample %d samples to %d\n", in_samples, out_samples); #endif - for (osample = 0; osample < out_samples - 1; osample++) { + for (osample = 0; osample < out_samples && isample >= 0xFFFF0000U; osample++) { + uint32_t t = isample&0xffff; + output_samples[osample*4 ] = (last_sample[0] * (0x10000-t) + input_samples[0] * t) >> 16; + output_samples[osample*4+1] = (last_sample[1] * (0x10000-t) + input_samples[1] * t) >> 16; + output_samples[osample*4+2] = (last_sample[2] * (0x10000-t) + input_samples[2] * t) >> 16; + output_samples[osample*4+3] = (last_sample[3] * (0x10000-t) + input_samples[3] * t) >> 16; + isample += istep; + } + + for (; osample < out_samples; osample++) { int s1; int s2; int16_t os; @@ -145,28 +170,35 @@ void _x_audio_out_resample_4channel(int16_t* input_samples, uint32_t in_samples, isample += istep; } - output_samples[out_samples*4-4] = input_samples[in_samples*4-4]; - output_samples[out_samples*4-3] = input_samples[in_samples*4-3]; - output_samples[out_samples*4-2] = input_samples[in_samples*4-2]; - output_samples[out_samples*4-1] = input_samples[in_samples*4-1]; - + memcpy (last_sample, &input_samples[in_samples*4-4], 4 * sizeof (last_sample[0])); } -void _x_audio_out_resample_5channel(int16_t* input_samples, uint32_t in_samples, +void _x_audio_out_resample_5channel(int16_t *last_sample, + int16_t* input_samples, uint32_t in_samples, int16_t* output_samples, uint32_t out_samples) { unsigned int osample; /* 16+16 fixed point math */ - uint32_t isample = 0; - uint32_t istep = ((in_samples-2) << 16)/(out_samples-2); + uint32_t isample = 0xFFFF0000U; + uint32_t istep = (in_samples << 16) / out_samples + 1; #ifdef VERBOSE printf ("Audio : resample %d samples to %d\n", in_samples, out_samples); #endif - for (osample = 0; osample < out_samples - 1; osample++) { + for (osample = 0; osample < out_samples && isample >= 0xFFFF0000U; osample++) { + uint32_t t = isample&0xffff; + output_samples[osample*5 ] = (last_sample[0] * (0x10000-t) + input_samples[0] * t) >> 16; + output_samples[osample*5+1] = (last_sample[1] * (0x10000-t) + input_samples[1] * t) >> 16; + output_samples[osample*5+2] = (last_sample[2] * (0x10000-t) + input_samples[2] * t) >> 16; + output_samples[osample*5+3] = (last_sample[3] * (0x10000-t) + input_samples[3] * t) >> 16; + output_samples[osample*5+4] = (last_sample[4] * (0x10000-t) + input_samples[4] * t) >> 16; + isample += istep; + } + + for (; osample < out_samples; osample++) { int s1; int s2; int16_t os; @@ -205,29 +237,36 @@ void _x_audio_out_resample_5channel(int16_t* input_samples, uint32_t in_samples, isample += istep; } - - output_samples[out_samples*5-5] = input_samples[in_samples*5-5]; - output_samples[out_samples*5-4] = input_samples[in_samples*5-4]; - output_samples[out_samples*5-3] = input_samples[in_samples*5-3]; - output_samples[out_samples*5-2] = input_samples[in_samples*5-2]; - output_samples[out_samples*5-1] = input_samples[in_samples*5-1]; + memcpy (last_sample, &input_samples[in_samples*5-5], 5 * sizeof (last_sample[0])); } -void _x_audio_out_resample_6channel(int16_t* input_samples, uint32_t in_samples, +void _x_audio_out_resample_6channel(int16_t *last_sample, + int16_t* input_samples, uint32_t in_samples, int16_t* output_samples, uint32_t out_samples) { unsigned int osample; /* 16+16 fixed point math */ - uint32_t isample = 0; - uint32_t istep = ((in_samples-2) << 16)/(out_samples-2); + uint32_t isample = 0xFFFF0000U; + uint32_t istep = (in_samples << 16) / out_samples + 1; #ifdef VERBOSE printf ("Audio : resample %d samples to %d\n", in_samples, out_samples); #endif - for (osample = 0; osample < out_samples - 1; osample++) { + for (osample = 0; osample < out_samples && isample >= 0xFFFF0000U; osample++) { + uint32_t t = isample&0xffff; + output_samples[osample*6 ] = (last_sample[0] * (0x10000-t) + input_samples[0] * t) >> 16; + output_samples[osample*6+1] = (last_sample[1] * (0x10000-t) + input_samples[1] * t) >> 16; + output_samples[osample*6+2] = (last_sample[2] * (0x10000-t) + input_samples[2] * t) >> 16; + output_samples[osample*6+3] = (last_sample[3] * (0x10000-t) + input_samples[3] * t) >> 16; + output_samples[osample*6+4] = (last_sample[4] * (0x10000-t) + input_samples[4] * t) >> 16; + output_samples[osample*6+5] = (last_sample[5] * (0x10000-t) + input_samples[5] * t) >> 16; + isample += istep; + } + + for (; osample < out_samples; osample++) { int s1; int s2; int16_t os; @@ -272,13 +311,7 @@ void _x_audio_out_resample_6channel(int16_t* input_samples, uint32_t in_samples, isample += istep; } - - output_samples[out_samples*6-6] = input_samples[in_samples*6-6]; - output_samples[out_samples*6-5] = input_samples[in_samples*6-5]; - output_samples[out_samples*6-4] = input_samples[in_samples*6-4]; - output_samples[out_samples*6-3] = input_samples[in_samples*6-3]; - output_samples[out_samples*6-2] = input_samples[in_samples*6-2]; - output_samples[out_samples*6-1] = input_samples[in_samples*6-1]; + memcpy (last_sample, &input_samples[in_samples*6-6], 6 * sizeof (last_sample[0])); } void _x_audio_out_resample_8to16(int8_t* input_samples, -- cgit v1.2.3