1 /* tinycap.c
2 **
3 ** Copyright 2011, The Android Open Source Project
4 **
5 ** Redistribution and use in source and binary forms, with or without
6 ** modification, are permitted provided that the following conditions are met:
7 ** * Redistributions of source code must retain the above copyright
8 ** notice, this list of conditions and the following disclaimer.
9 ** * Redistributions in binary form must reproduce the above copyright
10 ** notice, this list of conditions and the following disclaimer in the
11 ** documentation and/or other materials provided with the distribution.
12 ** * Neither the name of The Android Open Source Project nor the names of
13 ** its contributors may be used to endorse or promote products derived
14 ** from this software without specific prior written permission.
15 **
16 ** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND
17 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 ** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE
20 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 ** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
26 ** DAMAGE.
27 */
28
29 #include <tinyalsa/asoundlib.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <stdint.h>
33 #include <signal.h>
34
35 #define ID_RIFF 0x46464952
36 #define ID_WAVE 0x45564157
37 #define ID_FMT 0x20746d66
38 #define ID_DATA 0x61746164
39
40 #define FORMAT_PCM 1
41
42 struct wav_header {
43 uint32_t riff_id;
44 uint32_t riff_sz;
45 uint32_t riff_fmt;
46 uint32_t fmt_id;
47 uint32_t fmt_sz;
48 uint16_t audio_format;
49 uint16_t num_channels;
50 uint32_t sample_rate;
51 uint32_t byte_rate;
52 uint16_t block_align;
53 uint16_t bits_per_sample;
54 uint32_t data_id;
55 uint32_t data_sz;
56 };
57
58 int capturing = 1;
59
60 unsigned int capture_sample(FILE *file, unsigned int card, unsigned int device,
61 unsigned int channels, unsigned int rate,
62 unsigned int bits, unsigned int period_size,
63 unsigned int period_count);
64
sigint_handler(int sig)65 void sigint_handler(int sig)
66 {
67 capturing = 0;
68 }
69
main(int argc,char ** argv)70 int main(int argc, char **argv)
71 {
72 FILE *file;
73 struct wav_header header;
74 unsigned int card = 0;
75 unsigned int device = 0;
76 unsigned int channels = 2;
77 unsigned int rate = 44100;
78 unsigned int bits = 16;
79 unsigned int frames;
80 unsigned int period_size = 1024;
81 unsigned int period_count = 4;
82
83 if (argc < 2) {
84 fprintf(stderr, "Usage: %s file.wav [-D card] [-d device] [-c channels] "
85 "[-r rate] [-b bits] [-p period_size] [-n n_periods]\n", argv[0]);
86 return 1;
87 }
88
89 file = fopen(argv[1], "wb");
90 if (!file) {
91 fprintf(stderr, "Unable to create file '%s'\n", argv[1]);
92 return 1;
93 }
94
95 /* parse command line arguments */
96 argv += 2;
97 while (*argv) {
98 if (strcmp(*argv, "-d") == 0) {
99 argv++;
100 if (*argv)
101 device = atoi(*argv);
102 } else if (strcmp(*argv, "-c") == 0) {
103 argv++;
104 if (*argv)
105 channels = atoi(*argv);
106 } else if (strcmp(*argv, "-r") == 0) {
107 argv++;
108 if (*argv)
109 rate = atoi(*argv);
110 } else if (strcmp(*argv, "-b") == 0) {
111 argv++;
112 if (*argv)
113 bits = atoi(*argv);
114 } else if (strcmp(*argv, "-D") == 0) {
115 argv++;
116 if (*argv)
117 card = atoi(*argv);
118 } else if (strcmp(*argv, "-p") == 0) {
119 argv++;
120 if (*argv)
121 period_size = atoi(*argv);
122 } else if (strcmp(*argv, "-n") == 0) {
123 argv++;
124 if (*argv)
125 period_count = atoi(*argv);
126 }
127 if (*argv)
128 argv++;
129 }
130
131 header.riff_id = ID_RIFF;
132 header.riff_sz = 0;
133 header.riff_fmt = ID_WAVE;
134 header.fmt_id = ID_FMT;
135 header.fmt_sz = 16;
136 header.audio_format = FORMAT_PCM;
137 header.num_channels = channels;
138 header.sample_rate = rate;
139 header.byte_rate = (header.bits_per_sample / 8) * channels * rate;
140 header.block_align = channels * (header.bits_per_sample / 8);
141 header.bits_per_sample = bits;
142 header.data_id = ID_DATA;
143
144 /* leave enough room for header */
145 fseek(file, sizeof(struct wav_header), SEEK_SET);
146
147 /* install signal handler and begin capturing */
148 signal(SIGINT, sigint_handler);
149 frames = capture_sample(file, card, device, header.num_channels,
150 header.sample_rate, header.bits_per_sample,
151 period_size, period_count);
152 printf("Captured %d frames\n", frames);
153
154 /* write header now all information is known */
155 header.data_sz = frames * header.block_align;
156 fseek(file, 0, SEEK_SET);
157 fwrite(&header, sizeof(struct wav_header), 1, file);
158
159 fclose(file);
160
161 return 0;
162 }
163
capture_sample(FILE * file,unsigned int card,unsigned int device,unsigned int channels,unsigned int rate,unsigned int bits,unsigned int period_size,unsigned int period_count)164 unsigned int capture_sample(FILE *file, unsigned int card, unsigned int device,
165 unsigned int channels, unsigned int rate,
166 unsigned int bits, unsigned int period_size,
167 unsigned int period_count)
168 {
169 struct pcm_config config;
170 struct pcm *pcm;
171 char *buffer;
172 unsigned int size;
173 unsigned int bytes_read = 0;
174
175 config.channels = channels;
176 config.rate = rate;
177 config.period_size = period_size;
178 config.period_count = period_count;
179 if (bits == 32)
180 config.format = PCM_FORMAT_S32_LE;
181 else if (bits == 16)
182 config.format = PCM_FORMAT_S16_LE;
183 config.start_threshold = 0;
184 config.stop_threshold = 0;
185 config.silence_threshold = 0;
186
187 pcm = pcm_open(card, device, PCM_IN, &config);
188 if (!pcm || !pcm_is_ready(pcm)) {
189 fprintf(stderr, "Unable to open PCM device (%s)\n",
190 pcm_get_error(pcm));
191 return 0;
192 }
193
194 size = pcm_get_buffer_size(pcm);
195 buffer = malloc(size);
196 if (!buffer) {
197 fprintf(stderr, "Unable to allocate %d bytes\n", size);
198 free(buffer);
199 pcm_close(pcm);
200 return 0;
201 }
202
203 printf("Capturing sample: %u ch, %u hz, %u bit\n", channels, rate, bits);
204
205 while (capturing && !pcm_read(pcm, buffer, size)) {
206 if (fwrite(buffer, 1, size, file) != size) {
207 fprintf(stderr,"Error capturing sample\n");
208 break;
209 }
210 bytes_read += size;
211 }
212
213 free(buffer);
214 pcm_close(pcm);
215 return bytes_read / ((bits / 8) * channels);
216 }
217
218