examples/test.c


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
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <sysexits.h>
#include <fcntl.h>
#include <math.h>

#include <xas/synth.h>
#include <xas/audio.h>
#include <xas/mixer.h>
#include <xas/riff.h>

#define SYNTH_STATUS_CLEAR  0
#define SYNTH_STATUS_ON    (1 << 0)

typedef struct _synth_sine {
    int flags;
    float phase;

    size_t frequency;
} synth_sine;

static void usage(int argc, char **argv, const char *message, ...) {
    va_list args;

    va_start(args, message);

    if (message) {
        vfprintf(stderr, message, args);
        fputc('\n', stderr);
    }

    va_end(args);

    fprintf(stderr, "usage: %s output.wav\n", argv[0]);

    exit(EX_USAGE);
}

static int16_t sine_sample(xas_synth *synth, synth_sine *sine) {
    int16_t ret;
    static float tau = 2.0f * M_PI;

    if (sine->flags & SYNTH_STATUS_ON) {
        ret = (int16_t)roundf((INT16_MAX >> 2) * sinf(sine->phase));

        sine->phase += tau / (synth->sample_rate / sine->frequency);

        if (sine->phase > tau) {
            sine->phase -= tau;
        }
    } else {
        ret = 0;
    }

    return ret;
}

static void sine_cleanup(xas_synth *synth, synth_sine *sine) {
    return;
}

int main(int argc, char **argv) {
    xas_mixer *mixer;

    xas_audio_stream *synth_l,
                       *synth_r,
                       *wave;

    synth_sine sine_channels[2] = {
        { SYNTH_STATUS_ON, 0.0f, 220 },
        { SYNTH_STATUS_ON, 0.0f, 420 },
    };

    size_t sample_rate = 44100,
           duration_s  = 60,
           i;

    if (argc != 2) {
        usage(argc, argv, "No output file provided");
    }

    if ((wave = xas_riff_file_open(argv[1],
                                     XAS_AUDIO_STREAM_PCM_16_BIT,
                                     sample_rate,
                                     XAS_AUDIO_STREAM_STEREO,
                                     O_WRONLY | O_CREAT | O_TRUNC)) == NULL) {
        goto error_riff_file_open;
    }

    if ((synth_l = xas_synth_new(XAS_AUDIO_STREAM_PCM_16_BIT,
                                   sample_rate,
                                   sample_rate,
                                   (xas_synth_callback_sample)sine_sample,
                                   (xas_synth_callback_cleanup)sine_cleanup,
                                   &sine_channels[0])) == NULL) {
        goto error_synth_new_l;
    }

    if ((synth_r = xas_synth_new(XAS_AUDIO_STREAM_PCM_16_BIT,
                                   sample_rate,
                                   sample_rate,
                                   (xas_synth_callback_sample)sine_sample,
                                   (xas_synth_callback_cleanup)sine_cleanup,
                                   &sine_channels[1])) == NULL) {
        goto error_synth_new_r;
    }

    if ((mixer = xas_mixer_new(XAS_AUDIO_STREAM_PCM_16_BIT,
                                 sample_rate,
                                 XAS_AUDIO_STREAM_STEREO,
                                 sample_rate)) == NULL) {
        goto error_mixer_new;
    }

    if (xas_mixer_input_add(mixer, synth_l, 0.3, -1.0) == NULL) {
        goto error_mixer_input_add;
    }

    if (xas_mixer_input_add(mixer, synth_r, 0.3, 1.0) == NULL) {
        goto error_mixer_input_add;
    }

    for (i=0; i<duration_s; i++) {
        void *buf;
        ssize_t readlen;

        if ((readlen = xas_audio_stream_read(mixer->output,
                                               &buf,
                                               sample_rate)) < 0) {
            goto error_audio_stream_read;
        }

        if (xas_audio_stream_write(wave, buf, readlen) < 0) {
            goto error_audio_stream_write;
        }
    }

    xas_audio_stream_flush(wave);

    xas_mixer_destroy(mixer);
    xas_audio_stream_destroy(synth_r);
    xas_audio_stream_destroy(synth_l);
    xas_audio_stream_destroy(wave);

    return EX_OK;

error_audio_stream_write:
error_audio_stream_read:
error_mixer_input_add:
    xas_mixer_destroy(mixer);

error_mixer_new:
    xas_audio_stream_destroy(synth_r);

error_synth_new_r:
    xas_audio_stream_destroy(synth_l);

error_synth_new_l:
    xas_audio_stream_destroy(wave);

error_riff_file_open:
    return EX_OSERR;
}