xref: /btstack/platform/posix/wav_util.c (revision abc9118691c439b59ae8345cd3aab821aca3bb5b)
1 /*
2  * Copyright (C) 2016 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #include <stdint.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <fcntl.h>
43 #include <unistd.h>
44 
45 #include "wav_util.h"
46 #include "btstack_util.h"
47 
48 static const uint8_t sine[] = {
49       0,  15,  31,  46,  61,  74,  86,  97, 107, 114,
50     120, 124, 126, 126, 124, 120, 114, 107,  97,  86,
51      74,  61,  46,  31,  15,   0, 241, 225, 210, 195,
52     182, 170, 159, 149, 142, 136, 132, 130, 130, 132,
53     136, 142, 149, 159, 170, 182, 195, 210, 225, 241,
54 };
55 static int phase = 0;
56 
57 static int wav_reader_fd;
58 static int bytes_per_sample = 2;
59 
60 /* Write wav file utils */
61 typedef struct wav_writer_state {
62     FILE * wav_file;
63     int total_num_samples;
64     int num_channels;
65     int sampling_frequency;
66     int frame_count;
67 } wav_writer_state_t;
68 
69 wav_writer_state_t wav_writer_state;
70 
71 
72 static void little_endian_fstore_16(FILE *wav_file, uint16_t value){
73     uint8_t buf[2];
74     little_endian_store_16(buf, 0, value);
75     fwrite(&buf, 1, 2, wav_file);
76 }
77 
78 static void little_endian_fstore_32(FILE *wav_file, uint32_t value){
79     uint8_t buf[4];
80     little_endian_store_32(buf, 0, value);
81     fwrite(&buf, 1, 4, wav_file);
82 }
83 
84 static ssize_t __read(int fd, void *buf, size_t count){
85     ssize_t len, pos = 0;
86 
87     while (count > 0) {
88         len = read(fd, (int8_t * )buf + pos, count);
89         if (len <= 0)
90             return pos;
91 
92         count -= len;
93         pos   += len;
94     }
95     return pos;
96 }
97 
98 static void write_wav_header(FILE * wav_file,  int total_num_samples, int num_channels, int sample_rate){
99     unsigned int bytes_per_sample = 2;
100     /* write RIFF header */
101     fwrite("RIFF", 1, 4, wav_file);
102     // num_samples = blocks * subbands
103     uint32_t data_bytes = (uint32_t) (bytes_per_sample * total_num_samples * num_channels);
104     little_endian_fstore_32(wav_file, data_bytes + 36);
105     fwrite("WAVE", 1, 4, wav_file);
106 
107     int byte_rate = sample_rate * num_channels * bytes_per_sample;
108     int bits_per_sample = 8 * bytes_per_sample;
109     int block_align = num_channels * bits_per_sample;
110     int fmt_length = 16;
111     int fmt_format_tag = 1; // PCM
112 
113     /* write fmt chunk */
114     fwrite("fmt ", 1, 4, wav_file);
115     little_endian_fstore_32(wav_file, fmt_length);
116     little_endian_fstore_16(wav_file, fmt_format_tag);
117     little_endian_fstore_16(wav_file, num_channels);
118     little_endian_fstore_32(wav_file, sample_rate);
119     little_endian_fstore_32(wav_file, byte_rate);
120     little_endian_fstore_16(wav_file, block_align);
121     little_endian_fstore_16(wav_file, bits_per_sample);
122 
123     /* write data chunk */
124     fwrite("data", 1, 4, wav_file);
125     little_endian_fstore_32(wav_file, data_bytes);
126 }
127 
128 int wav_writer_open(const char * filepath, int num_channels, int sampling_frequency){
129     FILE * wav_file = fopen(filepath, "wb");
130     if (!wav_file) return 1;
131 
132     wav_writer_state.wav_file = wav_file;
133     wav_writer_state.frame_count = 0;
134     wav_writer_state.total_num_samples = 0;
135     wav_writer_state.num_channels = num_channels;
136     wav_writer_state.sampling_frequency = sampling_frequency;
137     write_wav_header(wav_writer_state.wav_file, 0, num_channels, sampling_frequency);
138     return 0;
139 }
140 
141 int wav_writer_close(void){
142     rewind(wav_writer_state.wav_file);
143     write_wav_header(wav_writer_state.wav_file, wav_writer_state.total_num_samples,
144         wav_writer_state.num_channels, wav_writer_state.sampling_frequency);
145     fclose(wav_writer_state.wav_file);
146     return 0;
147 }
148 
149 int wav_writer_write_int8(int num_samples, int8_t * data){
150     if (data == NULL) return 1;
151     int i = 0;
152     int8_t zero_byte = 0;
153     for (i=0; i<num_samples; i++){
154         fwrite(&zero_byte, 1, 1, wav_writer_state.wav_file);
155         uint8_t byte_value = (uint8_t)data[i];
156         fwrite(&byte_value, 1, 1, wav_writer_state.wav_file);
157     }
158 
159     wav_writer_state.total_num_samples+=num_samples;
160     wav_writer_state.frame_count++;
161     return 0;
162 }
163 
164 int wav_reader_open(const char * filepath){
165     wav_reader_fd = open(filepath, O_RDONLY);
166     if (!wav_reader_fd) {
167         printf("Can't open file %s", filepath);
168         return 1;
169     }
170 
171     uint8_t buf[40];
172     __read(wav_reader_fd, buf, sizeof(buf));
173 
174     int num_channels = little_endian_read_16(buf, 22);
175     int block_align = little_endian_read_16(buf, 32);
176     bytes_per_sample = block_align/num_channels;
177     if (bytes_per_sample > 2){
178         bytes_per_sample = bytes_per_sample/8;
179     }
180     return 0;
181 }
182 
183 int wav_reader_close(void){
184     close(wav_reader_fd);
185     return 0;
186 }
187 
188 // Wav data: 8bit is uint8_t; 16bit is int16
189 int wav_reader_read_int8(int num_samples, int8_t * data){
190     if (!wav_reader_fd) return 1;
191     int i;
192     int bytes_read = 0;
193 
194     for (i=0; i<num_samples; i++){
195         if (bytes_per_sample == 2){
196             uint8_t buf[2];
197             bytes_read +=__read(wav_reader_fd, &buf, 2);
198             data[i] = buf[1];
199         } else {
200             uint8_t buf[1];
201             bytes_read +=__read(wav_reader_fd, &buf, 1);
202             data[i] = buf[0] + 128;
203         }
204     }
205     return bytes_read == num_samples*bytes_per_sample;
206 }
207 
208 void wav_synthesize_sine_wave_int8(int num_samples, int8_t * data){
209     int i;
210     for (i=0; i<num_samples; i++){
211         data[i] = (int8_t)sine[phase];
212         phase++;
213         if (phase >= sizeof(sine)) phase = 0;
214     }
215 }
216 
217