xref: /btstack/platform/posix/wav_util.c (revision f12924e0a61c0582b548a1e70cea1bd59ba21f1d)
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 #include "btstack_debug.h"
48 
49 static int wav_reader_fd;
50 static int bytes_per_sample = 2;
51 
52 /* Write wav file utils */
53 typedef struct wav_writer_state {
54     FILE * wav_file;
55     int total_num_samples;
56     int num_channels;
57     int sampling_frequency;
58     int frame_count;
59 } wav_writer_state_t;
60 
61 wav_writer_state_t wav_writer_state;
62 
63 
64 static void little_endian_fstore_16(FILE *wav_file, uint16_t value){
65     uint8_t buf[2];
66     little_endian_store_16(buf, 0, value);
67     fwrite(&buf, 1, 2, wav_file);
68 }
69 
70 static void little_endian_fstore_32(FILE *wav_file, uint32_t value){
71     uint8_t buf[4];
72     little_endian_store_32(buf, 0, value);
73     fwrite(&buf, 1, 4, wav_file);
74 }
75 
76 static ssize_t __read(int fd, void *buf, size_t count){
77     ssize_t len, pos = 0;
78 
79     while (count > 0) {
80         len = read(fd, (int8_t * )buf + pos, count);
81         if (len <= 0)
82             return pos;
83 
84         count -= len;
85         pos   += len;
86     }
87     return pos;
88 }
89 
90 static void write_wav_header(FILE * wav_file,  int total_num_samples, int num_channels, int sample_rate){
91     unsigned int write_with_bytes_per_sample = 2;
92     /* write RIFF header */
93     fwrite("RIFF", 1, 4, wav_file);
94     // num_samples = blocks * subbands
95     uint32_t data_bytes = (uint32_t) (write_with_bytes_per_sample * total_num_samples * num_channels);
96     little_endian_fstore_32(wav_file, data_bytes + 36);
97     fwrite("WAVE", 1, 4, wav_file);
98 
99     int byte_rate = sample_rate * num_channels * write_with_bytes_per_sample;
100     int bits_per_sample = 8 * write_with_bytes_per_sample;
101     int block_align = num_channels * bits_per_sample;
102     int fmt_length = 16;
103     int fmt_format_tag = 1; // PCM
104 
105     /* write fmt chunk */
106     fwrite("fmt ", 1, 4, wav_file);
107     little_endian_fstore_32(wav_file, fmt_length);
108     little_endian_fstore_16(wav_file, fmt_format_tag);
109     little_endian_fstore_16(wav_file, num_channels);
110     little_endian_fstore_32(wav_file, sample_rate);
111     little_endian_fstore_32(wav_file, byte_rate);
112     little_endian_fstore_16(wav_file, block_align);
113     little_endian_fstore_16(wav_file, bits_per_sample);
114 
115     /* write data chunk */
116     fwrite("data", 1, 4, wav_file);
117     little_endian_fstore_32(wav_file, data_bytes);
118 }
119 
120 int wav_writer_open(const char * filepath, int num_channels, int sampling_frequency){
121     FILE * wav_file = fopen(filepath, "wb");
122     if (!wav_file) return 1;
123 
124     wav_writer_state.wav_file = wav_file;
125     wav_writer_state.frame_count = 0;
126     wav_writer_state.total_num_samples = 0;
127     wav_writer_state.num_channels = num_channels;
128     wav_writer_state.sampling_frequency = sampling_frequency;
129     write_wav_header(wav_writer_state.wav_file, 0, num_channels, sampling_frequency);
130     return 0;
131 }
132 
133 int wav_writer_close(void){
134     rewind(wav_writer_state.wav_file);
135     write_wav_header(wav_writer_state.wav_file, wav_writer_state.total_num_samples,
136         wav_writer_state.num_channels, wav_writer_state.sampling_frequency);
137     fclose(wav_writer_state.wav_file);
138     return 0;
139 }
140 
141 int wav_writer_write_int8(int num_samples, int8_t * data){
142     if (data == NULL) return 1;
143     int i = 0;
144     int8_t zero_byte = 0;
145     for (i=0; i<num_samples; i++){
146         fwrite(&zero_byte, 1, 1, wav_writer_state.wav_file);
147         uint8_t byte_value = (uint8_t)data[i];
148         fwrite(&byte_value, 1, 1, wav_writer_state.wav_file);
149     }
150 
151     wav_writer_state.total_num_samples+=num_samples;
152     wav_writer_state.frame_count++;
153     return 0;
154 }
155 
156 int wav_writer_write_le_int16(int num_samples, int16_t * data){
157     if (data == NULL) return 1;
158     fwrite(data, num_samples, 2, wav_writer_state.wav_file);
159 
160     wav_writer_state.total_num_samples+=num_samples;
161     wav_writer_state.frame_count++;
162     return 0;
163 }
164 
165 int wav_writer_write_int16(int num_samples, int16_t * data){
166     if (btstack_is_little_endian()){
167         return wav_writer_write_le_int16(num_samples, data);
168     }
169     if (data == NULL) return 1;
170 
171     int i;
172     for (i=0;i<num_samples;i++){
173         uint16_t sample = btstack_flip_16(data[i]);
174         fwrite(&sample, 1, 2, wav_writer_state.wav_file);
175     }
176 
177     wav_writer_state.total_num_samples+=num_samples;
178     wav_writer_state.frame_count++;
179     return 0;
180 }
181 
182 int wav_reader_open(const char * filepath){
183     wav_reader_fd = open(filepath, O_RDONLY);
184     if (!wav_reader_fd) {
185         log_error("Can't open file %s", filepath);
186         return 1;
187     }
188 
189     uint8_t buf[40];
190     __read(wav_reader_fd, buf, sizeof(buf));
191 
192     int num_channels = little_endian_read_16(buf, 22);
193     int block_align = little_endian_read_16(buf, 32);
194     if (num_channels != 1 && num_channels != 2) {
195         log_error("Unexpected num channels %d", num_channels);
196         return 1;
197     }
198     bytes_per_sample = block_align/num_channels;
199     if (bytes_per_sample > 2){
200         bytes_per_sample = bytes_per_sample/8;
201     }
202     return 0;
203 }
204 
205 int wav_reader_close(void){
206     close(wav_reader_fd);
207     return 0;
208 }
209 
210 // Wav data: 8bit is uint8_t; 16bit is int16
211 int wav_reader_read_int8(int num_samples, int8_t * data){
212     if (!wav_reader_fd) return 1;
213     int i;
214     int bytes_read = 0;
215 
216     for (i=0; i<num_samples; i++){
217         if (bytes_per_sample == 2){
218             uint8_t buf[2];
219             bytes_read +=__read(wav_reader_fd, &buf, 2);
220             data[i] = buf[1];
221         } else {
222             uint8_t buf[1];
223             bytes_read +=__read(wav_reader_fd, &buf, 1);
224             data[i] = buf[0] + 128;
225         }
226     }
227     return bytes_read == num_samples*bytes_per_sample;
228 }
229 
230 int wav_reader_read_int16(int num_samples, int16_t * data){
231     if (!wav_reader_fd) return 1;
232     int i;
233     int bytes_read = 0;
234     for (i=0; i<num_samples; i++){
235         uint8_t buf[2];
236         bytes_read +=__read(wav_reader_fd, &buf, 2);
237         data[i] = little_endian_read_16(buf, 0);
238     }
239     return bytes_read == num_samples*bytes_per_sample;
240 }
241 
242 
243