pinebuds/services/multimedia/speech/inc/crossfade.h
2022-08-15 17:20:27 +08:00

58 lines
No EOL
1.4 KiB
C

#ifndef CROSSFADE_H
#define CROSSFADE_H
#include <stdint.h>
enum CROSSFADE_STATUS_T {
CROSSFADE_STATUS_OK = 0,
CROSSFADE_STATUS_ERROR,
CROSSFADE_STATUS_NO_BUF,
CROSSFADE_STATUS_BUF_MISALIGN,
CROSSFADE_STATUS_BUF_TOO_SMALL,
};
typedef struct
{
float overlap_time;
float coef1;
float coef2;
void *buf;
uint32_t size;
} CrossFadeConfig;
typedef void *CrossFadeId;
#ifdef __cplusplus
extern "C" {
#endif
uint32_t crossfade_get_buffer_size(void);
enum CROSSFADE_STATUS_T crossfade_init(int32_t sample_rate, int32_t sample_bits, CrossFadeConfig *cfg, CrossFadeId *id);
void crossfade_destroy(CrossFadeId id);
/*
* outbuf = (1 - weight) * inbuf1 + weight * (coef1 * inbuf1 + coef2 * inbuf2)
* = (1 - weight + weight * coef1) * inbuf1 + weight * coef2 * inbuf2
* = (1 - (1 - coef1) * weight) * inbuf1 + weight * coef2 * inbuf2;
* out_ch_num = max(ch_num1, ch_num2);
* final data is outbuf = inbuf1 * coef1 + inbuf2 * coef2;
*
* fadein:
* crossfade_process(st, NULL, 1, inbuf, ch_num, outbuf, frame_size);
*
* fadeout:
* crossfade_process(st, inbuf, ch_num, NULL, 1, frame_size);
*
* crossfade: (ch_num1 == ch_num2 || ch_num1 == 1 || ch_num2 == 1)
* crossfade_process(st, inbuf1, ch_num1, inbuf2, ch_num2, outbuf, frame_size);
*/
bool crossfade_process(CrossFadeId id, void *inbuf1, int32_t ch_num1, void *inbuf2, int32_t ch_num2, void *outbuf, int32_t frame_size);
#ifdef __cplusplus
}
#endif
#endif