diff options
Diffstat (limited to 'src/audio_out/resample.c')
| -rw-r--r-- | src/audio_out/resample.c | 149 |
1 files changed, 148 insertions, 1 deletions
diff --git a/src/audio_out/resample.c b/src/audio_out/resample.c index 9f464b276..158b17c59 100644 --- a/src/audio_out/resample.c +++ b/src/audio_out/resample.c @@ -17,7 +17,7 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA * - * $Id: resample.c,v 1.1 2001/04/24 20:53:00 f1rmb Exp $ + * $Id: resample.c,v 1.2 2001/05/27 23:48:12 guenter Exp $ */ #ifdef HAVE_CONFIG_H @@ -28,6 +28,37 @@ /* contributed by paul flinders */ +void audio_out_resample_mono(int16_t* input_samples, uint32_t in_samples, + int16_t* output_samples, uint32_t out_samples) +{ + int osample; + /* 16+16 fixed point math */ + uint32_t isample = 0; + uint32_t istep = (in_samples << 16)/out_samples; + +#ifdef VERBOSE + printf ("Audio : resample %d samples to %d\n", + in_samples, out_samples); +#endif + + for (osample = 0; osample < out_samples - 1; osample++) { + int s1; + int s2; + int16_t os; + uint32_t t = isample&0xffff; + + /* don't "optimize" the (isample >> 16)*2 to (isample >> 15) */ + s1 = input_samples[(isample >> 16)]; + s2 = input_samples[(isample >> 16)+1]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[osample] = os; + + isample += istep; + } + output_samples[out_samples-1] = input_samples[in_samples-1]; +} + void audio_out_resample_stereo(int16_t* input_samples, uint32_t in_samples, int16_t* output_samples, uint32_t out_samples) { @@ -65,3 +96,119 @@ void audio_out_resample_stereo(int16_t* input_samples, uint32_t in_samples, output_samples[out_samples*2-1] = input_samples[in_samples*2-1]; } + +void audio_out_resample_4channel(int16_t* input_samples, uint32_t in_samples, + int16_t* output_samples, uint32_t out_samples) +{ + int osample; + /* 16+16 fixed point math */ + uint32_t isample = 0; + uint32_t istep = (in_samples << 16)/out_samples; + +#ifdef VERBOSE + printf ("Audio : resample %d samples to %d\n", + in_samples, out_samples); +#endif + + for (osample = 0; osample < out_samples - 1; osample++) { + int s1; + int s2; + int16_t os; + uint32_t t = isample&0xffff; + + /* don't "optimize" the (isample >> 16)*2 to (isample >> 15) */ + s1 = input_samples[(isample >> 16)*4]; + s2 = input_samples[(isample >> 16)*4+4]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[osample * 4] = os; + + s1 = input_samples[(isample >> 16)*4+1]; + s2 = input_samples[(isample >> 16)*4+5]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[(osample * 4 )+1] = os; + + s1 = input_samples[(isample >> 16)*4+2]; + s2 = input_samples[(isample >> 16)*4+6]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[(osample * 4 )+2] = os; + + s1 = input_samples[(isample >> 16)*4+3]; + s2 = input_samples[(isample >> 16)*4+7]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[(osample * 4 )+3] = os; + + 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]; + +} + + +void audio_out_resample_5channel(int16_t* input_samples, uint32_t in_samples, + int16_t* output_samples, uint32_t out_samples) +{ + int osample; + /* 16+16 fixed point math */ + uint32_t isample = 0; + uint32_t istep = (in_samples << 16)/out_samples; + +#ifdef VERBOSE + printf ("Audio : resample %d samples to %d\n", + in_samples, out_samples); +#endif + + for (osample = 0; osample < out_samples - 1; osample++) { + int s1; + int s2; + int16_t os; + uint32_t t = isample&0xffff; + + /* don't "optimize" the (isample >> 16)*2 to (isample >> 15) */ + s1 = input_samples[(isample >> 16)*5]; + s2 = input_samples[(isample >> 16)*5+5]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[osample * 5] = os; + + s1 = input_samples[(isample >> 16)*5+1]; + s2 = input_samples[(isample >> 16)*5+6]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[(osample * 5 )+1] = os; + + s1 = input_samples[(isample >> 16)*5+2]; + s2 = input_samples[(isample >> 16)*5+7]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[(osample * 5 )+2] = os; + + s1 = input_samples[(isample >> 16)*5+3]; + s2 = input_samples[(isample >> 16)*5+8]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[(osample * 5 )+3] = os; + + s1 = input_samples[(isample >> 16)*5+4]; + s2 = input_samples[(isample >> 16)*5+9]; + + os = (s1 * (0x10000-t)+ s2 * t) >> 16; + output_samples[(osample * 5 )+4] = os; + + 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]; +} + + |