virtualx-engine/servers/audio/audio_rb_resampler.h
2017-04-08 00:11:42 +02:00

160 lines
5.1 KiB
C++

/*************************************************************************/
/* audio_rb_resampler.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md) */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#ifndef AUDIO_RB_RESAMPLER_H
#define AUDIO_RB_RESAMPLER_H
#include "os/memory.h"
#include "typedefs.h"
struct AudioRBResampler {
uint32_t rb_bits;
uint32_t rb_len;
uint32_t rb_mask;
uint32_t read_buff_len;
uint32_t channels;
uint32_t src_mix_rate;
uint32_t target_mix_rate;
volatile int rb_read_pos;
volatile int rb_write_pos;
int32_t offset; //contains the fractional remainder of the resampler
enum {
MIX_FRAC_BITS = 13,
MIX_FRAC_LEN = (1 << MIX_FRAC_BITS),
MIX_FRAC_MASK = MIX_FRAC_LEN - 1,
};
int16_t *read_buf;
int16_t *rb;
template <int C>
uint32_t _resample(int32_t *p_dest, int p_todo, int32_t p_increment);
public:
_FORCE_INLINE_ void flush() {
rb_read_pos = 0;
rb_write_pos = 0;
offset = 0;
}
_FORCE_INLINE_ bool is_ready() const {
return rb != NULL;
}
_FORCE_INLINE_ int get_total() const {
return rb_len - 1;
}
_FORCE_INLINE_ int get_todo() const { //return amount of frames to mix
int todo;
int read_pos_cache = rb_read_pos;
if (read_pos_cache == rb_write_pos) {
todo = rb_len - 1;
} else if (read_pos_cache > rb_write_pos) {
todo = read_pos_cache - rb_write_pos - 1;
} else {
todo = (rb_len - rb_write_pos) + read_pos_cache - 1;
}
return todo;
}
_FORCE_INLINE_ bool has_data() const {
return rb && rb_read_pos != rb_write_pos;
}
_FORCE_INLINE_ int16_t *get_write_buffer() { return read_buf; }
_FORCE_INLINE_ void write(uint32_t p_frames) {
ERR_FAIL_COND(p_frames >= rb_len);
switch (channels) {
case 1: {
for (uint32_t i = 0; i < p_frames; i++) {
rb[rb_write_pos] = read_buf[i];
rb_write_pos = (rb_write_pos + 1) & rb_mask;
}
} break;
case 2: {
for (uint32_t i = 0; i < p_frames; i++) {
rb[(rb_write_pos << 1) + 0] = read_buf[(i << 1) + 0];
rb[(rb_write_pos << 1) + 1] = read_buf[(i << 1) + 1];
rb_write_pos = (rb_write_pos + 1) & rb_mask;
}
} break;
case 4: {
for (uint32_t i = 0; i < p_frames; i++) {
rb[(rb_write_pos << 2) + 0] = read_buf[(i << 2) + 0];
rb[(rb_write_pos << 2) + 1] = read_buf[(i << 2) + 1];
rb[(rb_write_pos << 2) + 2] = read_buf[(i << 2) + 2];
rb[(rb_write_pos << 2) + 3] = read_buf[(i << 2) + 3];
rb_write_pos = (rb_write_pos + 1) & rb_mask;
}
} break;
case 6: {
for (uint32_t i = 0; i < p_frames; i++) {
rb[(rb_write_pos * 6) + 0] = read_buf[(i * 6) + 0];
rb[(rb_write_pos * 6) + 1] = read_buf[(i * 6) + 1];
rb[(rb_write_pos * 6) + 2] = read_buf[(i * 6) + 2];
rb[(rb_write_pos * 6) + 3] = read_buf[(i * 6) + 3];
rb[(rb_write_pos * 6) + 4] = read_buf[(i * 6) + 4];
rb[(rb_write_pos * 6) + 5] = read_buf[(i * 6) + 5];
rb_write_pos = (rb_write_pos + 1) & rb_mask;
}
} break;
}
}
int get_channel_count() const;
Error setup(int p_channels, int p_src_mix_rate, int p_target_mix_rate, int p_buffer_msec, int p_minbuff_needed = -1);
void clear();
bool mix(int32_t *p_dest, int p_frames);
AudioRBResampler();
~AudioRBResampler();
};
#endif // AUDIO_RB_RESAMPLER_H