doxygen: misc consistency, spelling and wording fixes
[libav.git] / tests / audiogen.c
1 /*
2 * Generate a synthetic stereo sound.
3 * NOTE: No floats are used to guarantee bitexact output.
4 *
5 * Copyright (c) 2002 Fabrice Bellard
6 *
7 * This file is part of Libav.
8 *
9 * Libav is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * Libav is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with Libav; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 #include <stdlib.h>
25 #include <stdio.h>
26
27 #define MAX_CHANNELS 8
28
29 static unsigned int myrnd(unsigned int *seed_ptr, int n)
30 {
31 unsigned int seed, val;
32
33 seed = *seed_ptr;
34 seed = (seed * 314159) + 1;
35 if (n == 256) {
36 val = seed >> 24;
37 } else {
38 val = seed % n;
39 }
40 *seed_ptr = seed;
41 return val;
42 }
43
44 #define FRAC_BITS 16
45 #define FRAC_ONE (1 << FRAC_BITS)
46
47 #define COS_TABLE_BITS 7
48
49 /* integer cosinus */
50 static const unsigned short cos_table[(1 << COS_TABLE_BITS) + 2] = {
51 0x8000, 0x7ffe, 0x7ff6, 0x7fea, 0x7fd9, 0x7fc2, 0x7fa7, 0x7f87,
52 0x7f62, 0x7f38, 0x7f0a, 0x7ed6, 0x7e9d, 0x7e60, 0x7e1e, 0x7dd6,
53 0x7d8a, 0x7d3a, 0x7ce4, 0x7c89, 0x7c2a, 0x7bc6, 0x7b5d, 0x7aef,
54 0x7a7d, 0x7a06, 0x798a, 0x790a, 0x7885, 0x77fb, 0x776c, 0x76d9,
55 0x7642, 0x75a6, 0x7505, 0x7460, 0x73b6, 0x7308, 0x7255, 0x719e,
56 0x70e3, 0x7023, 0x6f5f, 0x6e97, 0x6dca, 0x6cf9, 0x6c24, 0x6b4b,
57 0x6a6e, 0x698c, 0x68a7, 0x67bd, 0x66d0, 0x65de, 0x64e9, 0x63ef,
58 0x62f2, 0x61f1, 0x60ec, 0x5fe4, 0x5ed7, 0x5dc8, 0x5cb4, 0x5b9d,
59 0x5a82, 0x5964, 0x5843, 0x571e, 0x55f6, 0x54ca, 0x539b, 0x5269,
60 0x5134, 0x4ffb, 0x4ec0, 0x4d81, 0x4c40, 0x4afb, 0x49b4, 0x486a,
61 0x471d, 0x45cd, 0x447b, 0x4326, 0x41ce, 0x4074, 0x3f17, 0x3db8,
62 0x3c57, 0x3af3, 0x398d, 0x3825, 0x36ba, 0x354e, 0x33df, 0x326e,
63 0x30fc, 0x2f87, 0x2e11, 0x2c99, 0x2b1f, 0x29a4, 0x2827, 0x26a8,
64 0x2528, 0x23a7, 0x2224, 0x209f, 0x1f1a, 0x1d93, 0x1c0c, 0x1a83,
65 0x18f9, 0x176e, 0x15e2, 0x1455, 0x12c8, 0x113a, 0x0fab, 0x0e1c,
66 0x0c8c, 0x0afb, 0x096b, 0x07d9, 0x0648, 0x04b6, 0x0324, 0x0192,
67 0x0000, 0x0000,
68 };
69
70 #define CSHIFT (FRAC_BITS - COS_TABLE_BITS - 2)
71
72 static int int_cos(int a)
73 {
74 int neg, v, f;
75 const unsigned short *p;
76
77 a = a & (FRAC_ONE - 1); /* modulo 2 * pi */
78 if (a >= (FRAC_ONE / 2))
79 a = FRAC_ONE - a;
80 neg = 0;
81 if (a > (FRAC_ONE / 4)) {
82 neg = -1;
83 a = (FRAC_ONE / 2) - a;
84 }
85 p = cos_table + (a >> CSHIFT);
86 /* linear interpolation */
87 f = a & ((1 << CSHIFT) - 1);
88 v = p[0] + (((p[1] - p[0]) * f + (1 << (CSHIFT - 1))) >> CSHIFT);
89 v = (v ^ neg) - neg;
90 v = v << (FRAC_BITS - 15);
91 return v;
92 }
93
94 FILE *outfile;
95
96 static void put_sample(int v)
97 {
98 fputc(v & 0xff, outfile);
99 fputc((v >> 8) & 0xff, outfile);
100 }
101
102 int main(int argc, char **argv)
103 {
104 int i, a, v, j, f, amp, ampa;
105 unsigned int seed = 1;
106 int tabf1[MAX_CHANNELS], tabf2[MAX_CHANNELS];
107 int taba[MAX_CHANNELS];
108 int sample_rate = 44100;
109 int nb_channels = 2;
110
111 if (argc < 2 || argc > 4) {
112 printf("usage: %s file [<sample rate> [<channels>]]\n"
113 "generate a test raw 16 bit audio stream\n"
114 "default: 44100 Hz stereo\n", argv[0]);
115 exit(1);
116 }
117
118 if (argc > 2) {
119 sample_rate = atoi(argv[2]);
120 if (sample_rate <= 0) {
121 fprintf(stderr, "invalid sample rate: %d\n", sample_rate);
122 return 1;
123 }
124 }
125
126 if (argc > 3) {
127 nb_channels = atoi(argv[3]);
128 if (nb_channels < 1 || nb_channels > MAX_CHANNELS) {
129 fprintf(stderr, "invalid number of channels: %d\n", nb_channels);
130 return 1;
131 }
132 }
133
134 outfile = fopen(argv[1], "wb");
135 if (!outfile) {
136 perror(argv[1]);
137 return 1;
138 }
139
140 /* 1 second of single freq sinus at 1000 Hz */
141 a = 0;
142 for(i=0;i<1 * sample_rate;i++) {
143 v = (int_cos(a) * 10000) >> FRAC_BITS;
144 for(j=0;j<nb_channels;j++)
145 put_sample(v);
146 a += (1000 * FRAC_ONE) / sample_rate;
147 }
148
149 /* 1 second of varing frequency between 100 and 10000 Hz */
150 a = 0;
151 for(i=0;i<1 * sample_rate;i++) {
152 v = (int_cos(a) * 10000) >> FRAC_BITS;
153 for(j=0;j<nb_channels;j++)
154 put_sample(v);
155 f = 100 + (((10000 - 100) * i) / sample_rate);
156 a += (f * FRAC_ONE) / sample_rate;
157 }
158
159 /* 0.5 second of low amplitude white noise */
160 for(i=0;i<sample_rate / 2;i++) {
161 v = myrnd(&seed, 20000) - 10000;
162 for(j=0;j<nb_channels;j++)
163 put_sample(v);
164 }
165
166 /* 0.5 second of high amplitude white noise */
167 for(i=0;i<sample_rate / 2;i++) {
168 v = myrnd(&seed, 65535) - 32768;
169 for(j=0;j<nb_channels;j++)
170 put_sample(v);
171 }
172
173 /* 1 second of unrelated ramps for each channel */
174 for(j=0;j<nb_channels;j++) {
175 taba[j] = 0;
176 tabf1[j] = 100 + myrnd(&seed, 5000);
177 tabf2[j] = 100 + myrnd(&seed, 5000);
178 }
179 for(i=0;i<1 * sample_rate;i++) {
180 for(j=0;j<nb_channels;j++) {
181 v = (int_cos(taba[j]) * 10000) >> FRAC_BITS;
182 put_sample(v);
183 f = tabf1[j] + (((tabf2[j] - tabf1[j]) * i) / sample_rate);
184 taba[j] += (f * FRAC_ONE) / sample_rate;
185 }
186 }
187
188 /* 2 seconds of 500 Hz with varying volume */
189 a = 0;
190 ampa = 0;
191 for(i=0;i<2 * sample_rate;i++) {
192 for(j=0;j<nb_channels;j++) {
193 amp = ((FRAC_ONE + int_cos(ampa)) * 5000) >> FRAC_BITS;
194 if (j & 1)
195 amp = 10000 - amp;
196 v = (int_cos(a) * amp) >> FRAC_BITS;
197 put_sample(v);
198 a += (500 * FRAC_ONE) / sample_rate;
199 ampa += (2 * FRAC_ONE) / sample_rate;
200 }
201 }
202
203 fclose(outfile);
204 return 0;
205 }