diff options
Diffstat (limited to 'src/pcm/pcm_resample.h')
-rw-r--r-- | src/pcm/pcm_resample.h | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/src/pcm/pcm_resample.h b/src/pcm/pcm_resample.h new file mode 100644 index 000000000..a49a24142 --- /dev/null +++ b/src/pcm/pcm_resample.h @@ -0,0 +1,164 @@ +/* + * 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. + */ + +#ifndef MPD_PCM_RESAMPLE_H +#define MPD_PCM_RESAMPLE_H + +#include "check.h" +#include "pcm_buffer.h" + +#include <stdint.h> +#include <stddef.h> +#include <stdbool.h> + +#ifdef HAVE_LIBSAMPLERATE +#include <samplerate.h> +#endif + +/** + * This object is statically allocated (within another struct), and + * holds buffer allocations and the state for the resampler. + */ +struct pcm_resample_state { +#ifdef HAVE_LIBSAMPLERATE + SRC_STATE *state; + SRC_DATA data; + + struct pcm_buffer in, out; + + struct { + unsigned src_rate; + unsigned dest_rate; + unsigned channels; + } prev; + + int error; +#endif + + struct pcm_buffer buffer; +}; + +bool +pcm_resample_global_init(GError **error_r); + +/** + * Initializes a pcm_resample_state object. + */ +void pcm_resample_init(struct pcm_resample_state *state); + +/** + * Deinitializes a pcm_resample_state object and frees allocated + * memory. + */ +void pcm_resample_deinit(struct pcm_resample_state *state); + +/** + * @see pcm_convert_reset() + */ +void +pcm_resample_reset(struct pcm_resample_state *state); + +/** + * Resamples 32 bit float data. + * + * @param state an initialized pcm_resample_state object + * @param channels the number of channels + * @param src_rate the source sample rate + * @param src the source PCM buffer + * @param src_size the size of #src in bytes + * @param dest_rate the requested destination sample rate + * @param dest_size_r returns the number of bytes of the destination buffer + * @return the destination buffer + */ +const float * +pcm_resample_float(struct pcm_resample_state *state, + unsigned channels, + unsigned src_rate, + const float *src_buffer, size_t src_size, + unsigned dest_rate, size_t *dest_size_r, + GError **error_r); + +/** + * Resamples 16 bit PCM data. + * + * @param state an initialized pcm_resample_state object + * @param channels the number of channels + * @param src_rate the source sample rate + * @param src the source PCM buffer + * @param src_size the size of #src in bytes + * @param dest_rate the requested destination sample rate + * @param dest_size_r returns the number of bytes of the destination buffer + * @return the destination buffer + */ +const int16_t * +pcm_resample_16(struct pcm_resample_state *state, + unsigned channels, + unsigned src_rate, + const int16_t *src_buffer, size_t src_size, + unsigned dest_rate, size_t *dest_size_r, + GError **error_r); + +/** + * Resamples 32 bit PCM data. + * + * @param state an initialized pcm_resample_state object + * @param channels the number of channels + * @param src_rate the source sample rate + * @param src the source PCM buffer + * @param src_size the size of #src in bytes + * @param dest_rate the requested destination sample rate + * @param dest_size_r returns the number of bytes of the destination buffer + * @return the destination buffer + */ +const int32_t * +pcm_resample_32(struct pcm_resample_state *state, + unsigned channels, + unsigned src_rate, + const int32_t *src_buffer, size_t src_size, + unsigned dest_rate, size_t *dest_size_r, + GError **error_r); + +/** + * Resamples 24 bit PCM data. + * + * @param state an initialized pcm_resample_state object + * @param channels the number of channels + * @param src_rate the source sample rate + * @param src the source PCM buffer + * @param src_size the size of #src in bytes + * @param dest_rate the requested destination sample rate + * @param dest_size_r returns the number of bytes of the destination buffer + * @return the destination buffer + */ +static inline const int32_t * +pcm_resample_24(struct pcm_resample_state *state, + unsigned channels, + unsigned src_rate, + const int32_t *src_buffer, size_t src_size, + unsigned dest_rate, size_t *dest_size_r, + GError **error_r) +{ + /* reuse the 32 bit code - the resampler code doesn't care if + the upper 8 bits are actually used */ + return pcm_resample_32(state, channels, + src_rate, src_buffer, src_size, + dest_rate, dest_size_r, error_r); +} + +#endif |