Repository navigation
Expand file tree
/
Copy pathsynth_whitenoise_f32.cpp
More file actions
125 lines (113 loc) · 4.01 KB
/
Copy pathsynth_whitenoise_f32.cpp
File metadata and controls
125 lines (113 loc) · 4.01 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
/*
Extended to F32
Created: Chip Audette, OpenAudio, Feb 2017
License: MIT License. Use at your own risk.
*/
/* Audio Library for Teensy 3.X
* Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com
*
* Development of this audio library was funded by PJRC.COM, LLC by sales of
* Teensy and Audio Adaptor boards. Please support PJRC's efforts to develop
* open source software by purchasing Teensy or other PJRC products.
*
* 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, development funding 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.
*/
#include "synth_whitenoise_f32.h"
#include "input_i2s_f32.h" //for the audio_convert_i16_to_f32 routine
// Park-Miller-Carta Pseudo-Random Number Generator
// http://www.firstpr.com.au/dsp/rand31/
void AudioSynthNoiseWhite_F32::update(void)
{
audio_block_t *block;
audio_block_f32_t *block_f32;
uint32_t *p, *end;
int32_t n1, n2, gain;
uint32_t lo, hi, val1, val2;
//Serial.println("synth_whitenoise: update()");
gain = level;
if (gain == 0) {
//Serial.println(": Gain = 0, returning.");
return;
}
block = AudioStream::allocate();
block_f32 = AudioStream_F32::allocate_f32();
if (!block | !block_f32) {
//Serial.println(": NULL block. returning.");
return;
}
p = (uint32_t *)(block->data);
//end = p + AUDIO_BLOCK_SAMPLES/2;
end = p + (block_f32->length)/2;
lo = seed;
do {
#if defined(KINETISK)
hi = multiply_16bx16t(16807, lo); // 16807 * (lo >> 16)
lo = 16807 * (lo & 0xFFFF);
lo += (hi & 0x7FFF) << 16;
lo += hi >> 15;
lo = (lo & 0x7FFFFFFF) + (lo >> 31);
n1 = signed_multiply_32x16b(gain, lo);
hi = multiply_16bx16t(16807, lo); // 16807 * (lo >> 16)
lo = 16807 * (lo & 0xFFFF);
lo += (hi & 0x7FFF) << 16;
lo += hi >> 15;
lo = (lo & 0x7FFFFFFF) + (lo >> 31);
n2 = signed_multiply_32x16b(gain, lo);
val1 = pack_16b_16b(n2, n1);
hi = multiply_16bx16t(16807, lo); // 16807 * (lo >> 16)
lo = 16807 * (lo & 0xFFFF);
lo += (hi & 0x7FFF) << 16;
lo += hi >> 15;
lo = (lo & 0x7FFFFFFF) + (lo >> 31);
n1 = signed_multiply_32x16b(gain, lo);
hi = multiply_16bx16t(16807, lo); // 16807 * (lo >> 16)
lo = 16807 * (lo & 0xFFFF);
lo += (hi & 0x7FFF) << 16;
lo += hi >> 15;
lo = (lo & 0x7FFFFFFF) + (lo >> 31);
n2 = signed_multiply_32x16b(gain, lo);
val2 = pack_16b_16b(n2, n1);
*p++ = val1;
*p++ = val2;
#elif defined(KINETISL)
hi = 16807 * (lo >> 16);
lo = 16807 * (lo & 0xFFFF);
lo += (hi & 0x7FFF) << 16;
lo += hi >> 15;
lo = (lo & 0x7FFFFFFF) + (lo >> 31);
n1 = signed_multiply_32x16b(gain, lo);
hi = 16807 * (lo >> 16);
lo = 16807 * (lo & 0xFFFF);
lo += (hi & 0x7FFF) << 16;
lo += hi >> 15;
lo = (lo & 0x7FFFFFFF) + (lo >> 31);
n2 = signed_multiply_32x16b(gain, lo);
val1 = pack_16b_16b(n2, n1);
*p++ = val1;
#endif
} while (p < end);
seed = lo;
//convert int16 to f32
AudioInputI2S_F32::convert_i16_to_f32(block->data,block_f32->data,block_f32->length);
AudioStream_F32::transmit(block_f32);
AudioStream_F32::release(block_f32);
AudioStream::release(block);
//Serial.println(" Done.");
}
uint16_t AudioSynthNoiseWhite_F32::instance_count = 0;