xref: /btstack/platform/posix/wav_util.c (revision 25234a7e05f3e69524e0ba3eec834a229a86d91b)
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 int wav_reader_fd;
49 static int bytes_per_sample = 2;
50 
51 /* Write wav file utils */
52 typedef struct wav_writer_state {
53     FILE * wav_file;
54     int total_num_samples;
55     int num_channels;
56     int sampling_frequency;
57     int frame_count;
58 } wav_writer_state_t;
59 
60 wav_writer_state_t wav_writer_state;
61 
62 
63 static void little_endian_fstore_16(FILE *wav_file, uint16_t value){
64     uint8_t buf[2];
65     little_endian_store_16(buf, 0, value);
66     fwrite(&buf, 1, 2, wav_file);
67 }
68 
69 static void little_endian_fstore_32(FILE *wav_file, uint32_t value){
70     uint8_t buf[4];
71     little_endian_store_32(buf, 0, value);
72     fwrite(&buf, 1, 4, wav_file);
73 }
74 
75 static ssize_t __read(int fd, void *buf, size_t count){
76     ssize_t len, pos = 0;
77 
78     while (count > 0) {
79         len = read(fd, (int8_t * )buf + pos, count);
80         if (len <= 0)
81             return pos;
82 
83         count -= len;
84         pos   += len;
85     }
86     return pos;
87 }
88 
89 static void write_wav_header(FILE * wav_file,  int total_num_samples, int num_channels, int sample_rate){
90     unsigned int write_with_bytes_per_sample = 2;
91     /* write RIFF header */
92     fwrite("RIFF", 1, 4, wav_file);
93     // num_samples = blocks * subbands
94     uint32_t data_bytes = (uint32_t) (write_with_bytes_per_sample * total_num_samples * num_channels);
95     little_endian_fstore_32(wav_file, data_bytes + 36);
96     fwrite("WAVE", 1, 4, wav_file);
97 
98     int byte_rate = sample_rate * num_channels * write_with_bytes_per_sample;
99     int bits_per_sample = 8 * write_with_bytes_per_sample;
100     int block_align = num_channels * bits_per_sample;
101     int fmt_length = 16;
102     int fmt_format_tag = 1; // PCM
103 
104     /* write fmt chunk */
105     fwrite("fmt ", 1, 4, wav_file);
106     little_endian_fstore_32(wav_file, fmt_length);
107     little_endian_fstore_16(wav_file, fmt_format_tag);
108     little_endian_fstore_16(wav_file, num_channels);
109     little_endian_fstore_32(wav_file, sample_rate);
110     little_endian_fstore_32(wav_file, byte_rate);
111     little_endian_fstore_16(wav_file, block_align);
112     little_endian_fstore_16(wav_file, bits_per_sample);
113 
114     /* write data chunk */
115     fwrite("data", 1, 4, wav_file);
116     little_endian_fstore_32(wav_file, data_bytes);
117 }
118 
119 int wav_writer_open(const char * filepath, int num_channels, int sampling_frequency){
120     FILE * wav_file = fopen(filepath, "wb");
121     if (!wav_file) return 1;
122 
123     wav_writer_state.wav_file = wav_file;
124     wav_writer_state.frame_count = 0;
125     wav_writer_state.total_num_samples = 0;
126     wav_writer_state.num_channels = num_channels;
127     wav_writer_state.sampling_frequency = sampling_frequency;
128     write_wav_header(wav_writer_state.wav_file, 0, num_channels, sampling_frequency);
129     return 0;
130 }
131 
132 int wav_writer_close(void){
133     rewind(wav_writer_state.wav_file);
134     write_wav_header(wav_writer_state.wav_file, wav_writer_state.total_num_samples,
135         wav_writer_state.num_channels, wav_writer_state.sampling_frequency);
136     fclose(wav_writer_state.wav_file);
137     return 0;
138 }
139 
140 int wav_writer_write_int8(int num_samples, int8_t * data){
141     if (data == NULL) return 1;
142     int i = 0;
143     int8_t zero_byte = 0;
144     for (i=0; i<num_samples; i++){
145         fwrite(&zero_byte, 1, 1, wav_writer_state.wav_file);
146         uint8_t byte_value = (uint8_t)data[i];
147         fwrite(&byte_value, 1, 1, wav_writer_state.wav_file);
148     }
149 
150     wav_writer_state.total_num_samples+=num_samples;
151     wav_writer_state.frame_count++;
152     return 0;
153 }
154 
155 int wav_writer_write_int16(int num_samples, int16_t * data){
156     if (data == NULL) return 1;
157     fwrite(data, num_samples, 2, wav_writer_state.wav_file);
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 int wav_reader_read_int16(int num_samples, int16_t * data){
209     if (!wav_reader_fd) return 1;
210     int i;
211     int bytes_read = 0;
212     for (i=0; i<num_samples; i++){
213         uint8_t buf[2];
214         bytes_read +=__read(wav_reader_fd, &buf, 2);
215         data[i] = little_endian_read_16(buf, 0);
216     }
217     return bytes_read == num_samples*bytes_per_sample;
218 }
219 
220 
221