1 /* Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
2  * Use of this source code is governed by a BSD-style license that can be
3  * found in the LICENSE file.
4  */
5 
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <fcntl.h>
9 #include <sys/stat.h>
10 #include <sys/types.h>
11 #include <unistd.h>
12 
read_raw(const char * filename,size_t * frames)13 float *read_raw(const char *filename, size_t *frames)
14 {
15 	struct stat st;
16 	int16_t *buf;
17 	size_t f, n;
18 	int fd;
19 	float *data;
20 	int i;
21 
22 	if (stat(filename, &st) < 0) {
23 		fprintf(stderr, "cannot stat file %s\n", filename);
24 		return NULL;
25 	}
26 
27 	fd = open(filename, O_RDONLY);
28 	if (fd < 0) {
29 		fprintf(stderr, "cannot open file %s\n", filename);
30 		return NULL;
31 	}
32 
33 	f = st.st_size / 4;
34 	n = f * 4;
35 	buf = (int16_t *)malloc(n);
36 	if (read(fd, buf, n) != n) {
37 		fprintf(stderr, "short read %zu\n", n);
38 		free(buf);
39 		return NULL;
40 	}
41 	close(fd);
42 
43 	/* deinterleave and convert to float */
44 	data = (float *)malloc(sizeof(float) * f * 2);
45 	for (i = 0; i < f; i++) {
46 		data[i] = buf[2*i] / 32768.0f;
47 		data[i + f] = buf[2*i+1] / 32768.0f;
48 	}
49 	free(buf);
50 	*frames = f;
51 	return data;
52 }
53 
f2s16(float f)54 static int16_t f2s16(float f)
55 {
56 	int i;
57 	f *= 32768;
58 	i = (int)((f > 0) ? (f + 0.5f) : (f - 0.5f));
59 	if (i < -32768)
60 		i = -32768;
61 	else if (i > 32767)
62 		i = 32767;
63 	return (int16_t)i;
64 }
65 
write_raw(const char * filename,float * input,size_t frames)66 int write_raw(const char *filename, float *input, size_t frames)
67 {
68 	int16_t *buf;
69 	int rc = -1;
70 	int n = frames * 4;
71 	int i;
72 
73 	buf = (int16_t *)malloc(n);
74 	for (i = 0; i < frames; i++) {
75 		buf[2*i] = f2s16(input[i]);
76 		buf[2*i+1] = f2s16(input[i + frames]);
77 	}
78 
79 	int fd = open(filename, O_WRONLY | O_CREAT, 0644);
80 	if (fd < 0) {
81 		fprintf(stderr, "cannot open file %s\n", filename);
82 		goto quit;
83 	}
84 	if (write(fd, buf, n) != n) {
85 		fprintf(stderr, "short write file %s\n", filename);
86 		goto quit;
87 	}
88 	rc = 0;
89 quit:
90 	close(fd);
91 	free(buf);
92 	return rc;
93 }
94