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Diffstat (limited to 'src/PcmMix.cxx')
| -rw-r--r-- | src/PcmMix.cxx | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/src/PcmMix.cxx b/src/PcmMix.cxx new file mode 100644 index 00000000..8435c0c2 --- /dev/null +++ b/src/PcmMix.cxx @@ -0,0 +1,211 @@ +/* + * Copyright (C) 2003-2011 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "config.h" +#include "PcmMix.hxx" +#include "PcmVolume.hxx" +#include "PcmUtils.hxx" +#include "audio_format.h" + +#include <math.h> + +template<typename T, typename U, unsigned bits> +static T +PcmAddVolume(T _a, T _b, int volume1, int volume2) +{ + U a(_a), b(_b); + + U c = ((a * volume1 + b * volume2) + + pcm_volume_dither() + PCM_VOLUME_1 / 2) + / PCM_VOLUME_1; + + return PcmClamp<T, U, bits>(c); +} + +template<typename T, typename U, unsigned bits> +static void +PcmAddVolume(T *a, const T *b, unsigned n, int volume1, int volume2) +{ + for (size_t i = 0; i != n; ++i) + a[i] = PcmAddVolume<T, U, bits>(a[i], b[i], volume1, volume2); +} + +template<typename T, typename U, unsigned bits> +static void +PcmAddVolumeVoid(void *a, const void *b, size_t size, int volume1, int volume2) +{ + constexpr size_t sample_size = sizeof(T); + assert(size % sample_size == 0); + + PcmAddVolume<T, U, bits>((T *)a, (const T *)b, size / sample_size, + volume1, volume2); +} + +static void +pcm_add_vol_float(float *buffer1, const float *buffer2, + unsigned num_samples, float volume1, float volume2) +{ + while (num_samples > 0) { + float sample1 = *buffer1; + float sample2 = *buffer2++; + + sample1 = (sample1 * volume1 + sample2 * volume2); + *buffer1++ = sample1; + --num_samples; + } +} + +static bool +pcm_add_vol(void *buffer1, const void *buffer2, size_t size, + int vol1, int vol2, + enum sample_format format) +{ + switch (format) { + case SAMPLE_FORMAT_UNDEFINED: + case SAMPLE_FORMAT_DSD: + /* not implemented */ + return false; + + case SAMPLE_FORMAT_S8: + PcmAddVolumeVoid<int8_t, int32_t, 8>(buffer1, buffer2, size, + vol1, vol2); + return true; + + case SAMPLE_FORMAT_S16: + PcmAddVolumeVoid<int16_t, int32_t, 16>(buffer1, buffer2, size, + vol1, vol2); + return true; + + case SAMPLE_FORMAT_S24_P32: + PcmAddVolumeVoid<int32_t, int64_t, 24>(buffer1, buffer2, size, + vol1, vol2); + return true; + + case SAMPLE_FORMAT_S32: + PcmAddVolumeVoid<int32_t, int64_t, 32>(buffer1, buffer2, size, + vol1, vol2); + return true; + + case SAMPLE_FORMAT_FLOAT: + pcm_add_vol_float((float *)buffer1, (const float *)buffer2, + size / 4, + pcm_volume_to_float(vol1), + pcm_volume_to_float(vol2)); + return true; + } + + /* unreachable */ + assert(false); + return false; +} + +template<typename T, typename U, unsigned bits> +static T +PcmAdd(T _a, T _b) +{ + U a(_a), b(_b); + return PcmClamp<T, U, bits>(a + b); +} + +template<typename T, typename U, unsigned bits> +static void +PcmAdd(T *a, const T *b, unsigned n) +{ + for (size_t i = 0; i != n; ++i) + a[i] = PcmAdd<T, U, bits>(a[i], b[i]); +} + +template<typename T, typename U, unsigned bits> +static void +PcmAddVoid(void *a, const void *b, size_t size) +{ + constexpr size_t sample_size = sizeof(T); + assert(size % sample_size == 0); + + PcmAdd<T, U, bits>((T *)a, (const T *)b, size / sample_size); +} + +static void +pcm_add_float(float *buffer1, const float *buffer2, unsigned num_samples) +{ + while (num_samples > 0) { + float sample1 = *buffer1; + float sample2 = *buffer2++; + *buffer1++ = sample1 + sample2; + --num_samples; + } +} + +static bool +pcm_add(void *buffer1, const void *buffer2, size_t size, + enum sample_format format) +{ + switch (format) { + case SAMPLE_FORMAT_UNDEFINED: + case SAMPLE_FORMAT_DSD: + /* not implemented */ + return false; + + case SAMPLE_FORMAT_S8: + PcmAddVoid<int8_t, int32_t, 8>(buffer1, buffer2, size); + return true; + + case SAMPLE_FORMAT_S16: + PcmAddVoid<int16_t, int32_t, 16>(buffer1, buffer2, size); + return true; + + case SAMPLE_FORMAT_S24_P32: + PcmAddVoid<int32_t, int64_t, 24>(buffer1, buffer2, size); + return true; + + case SAMPLE_FORMAT_S32: + PcmAddVoid<int32_t, int64_t, 32>(buffer1, buffer2, size); + return true; + + case SAMPLE_FORMAT_FLOAT: + pcm_add_float((float *)buffer1, (const float *)buffer2, + size / 4); + return true; + } + + /* unreachable */ + assert(false); + return false; +} + +bool +pcm_mix(void *buffer1, const void *buffer2, size_t size, + enum sample_format format, float portion1) +{ + int vol1; + float s; + + /* portion1 is between 0.0 and 1.0 for crossfading, MixRamp uses NaN + * to signal mixing rather than fading */ + if (isnan(portion1)) + return pcm_add(buffer1, buffer2, size, format); + + s = sin(M_PI_2 * portion1); + s *= s; + + vol1 = s * PCM_VOLUME_1 + 0.5; + vol1 = vol1 > PCM_VOLUME_1 ? PCM_VOLUME_1 : (vol1 < 0 ? 0 : vol1); + + return pcm_add_vol(buffer1, buffer2, size, vol1, PCM_VOLUME_1 - vol1, format); +} |