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 #include <string.h> 35 36 #define ID_RIFF 0x46464952 37 #define ID_WAVE 0x45564157 38 #define ID_FMT 0x20746d66 39 #define ID_DATA 0x61746164 40 41 #define FORMAT_PCM 1 42 43 struct wav_header { 44 uint32_t riff_id; 45 uint32_t riff_sz; 46 uint32_t riff_fmt; 47 uint32_t fmt_id; 48 uint32_t fmt_sz; 49 uint16_t audio_format; 50 uint16_t num_channels; 51 uint32_t sample_rate; 52 uint32_t byte_rate; 53 uint16_t block_align; 54 uint16_t bits_per_sample; 55 uint32_t data_id; 56 uint32_t data_sz; 57 }; 58 59 int capturing = 1; 60 61 unsigned int capture_sample(FILE *file, unsigned int card, unsigned int device, 62 unsigned int channels, unsigned int rate, 63 enum pcm_format format, unsigned int period_size, 64 unsigned int period_count); 65 66 void sigint_handler(int sig) 67 { 68 capturing = 0; 69 } 70 71 int main(int argc, char **argv) 72 { 73 FILE *file; 74 struct wav_header header; 75 unsigned int card = 0; 76 unsigned int device = 0; 77 unsigned int channels = 2; 78 unsigned int rate = 44100; 79 unsigned int bits = 16; 80 unsigned int frames; 81 unsigned int period_size = 1024; 82 unsigned int period_count = 4; 83 enum pcm_format format; 84 85 if (argc < 2) { 86 fprintf(stderr, "Usage: %s file.wav [-D card] [-d device] [-c channels] " 87 "[-r rate] [-b bits] [-p period_size] [-n n_periods]\n", argv[0]); 88 return 1; 89 } 90 91 file = fopen(argv[1], "wb"); 92 if (!file) { 93 fprintf(stderr, "Unable to create file '%s'\n", argv[1]); 94 return 1; 95 } 96 97 /* parse command line arguments */ 98 argv += 2; 99 while (*argv) { 100 if (strcmp(*argv, "-d") == 0) { 101 argv++; 102 if (*argv) 103 device = atoi(*argv); 104 } else if (strcmp(*argv, "-c") == 0) { 105 argv++; 106 if (*argv) 107 channels = atoi(*argv); 108 } else if (strcmp(*argv, "-r") == 0) { 109 argv++; 110 if (*argv) 111 rate = atoi(*argv); 112 } else if (strcmp(*argv, "-b") == 0) { 113 argv++; 114 if (*argv) 115 bits = atoi(*argv); 116 } else if (strcmp(*argv, "-D") == 0) { 117 argv++; 118 if (*argv) 119 card = atoi(*argv); 120 } else if (strcmp(*argv, "-p") == 0) { 121 argv++; 122 if (*argv) 123 period_size = atoi(*argv); 124 } else if (strcmp(*argv, "-n") == 0) { 125 argv++; 126 if (*argv) 127 period_count = atoi(*argv); 128 } 129 if (*argv) 130 argv++; 131 } 132 133 header.riff_id = ID_RIFF; 134 header.riff_sz = 0; 135 header.riff_fmt = ID_WAVE; 136 header.fmt_id = ID_FMT; 137 header.fmt_sz = 16; 138 header.audio_format = FORMAT_PCM; 139 header.num_channels = channels; 140 header.sample_rate = rate; 141 142 switch (bits) { 143 case 32: 144 format = PCM_FORMAT_S32_LE; 145 break; 146 case 24: 147 format = PCM_FORMAT_S24_LE; 148 break; 149 case 16: 150 format = PCM_FORMAT_S16_LE; 151 break; 152 default: 153 fprintf(stderr, "%d bits is not supported.\n", bits); 154 return 1; 155 } 156 157 header.bits_per_sample = pcm_format_to_bits(format); 158 header.byte_rate = (header.bits_per_sample / 8) * channels * rate; 159 header.block_align = channels * (header.bits_per_sample / 8); 160 header.data_id = ID_DATA; 161 162 /* leave enough room for header */ 163 fseek(file, sizeof(struct wav_header), SEEK_SET); 164 165 /* install signal handler and begin capturing */ 166 signal(SIGINT, sigint_handler); 167 frames = capture_sample(file, card, device, header.num_channels, 168 header.sample_rate, format, 169 period_size, period_count); 170 printf("Captured %d frames\n", frames); 171 172 /* write header now all information is known */ 173 header.data_sz = frames * header.block_align; 174 header.riff_sz = header.data_sz + sizeof(header) - 8; 175 fseek(file, 0, SEEK_SET); 176 fwrite(&header, sizeof(struct wav_header), 1, file); 177 178 fclose(file); 179 180 return 0; 181 } 182 183 unsigned int capture_sample(FILE *file, unsigned int card, unsigned int device, 184 unsigned int channels, unsigned int rate, 185 enum pcm_format format, unsigned int period_size, 186 unsigned int period_count) 187 { 188 struct pcm_config config; 189 struct pcm *pcm; 190 char *buffer; 191 unsigned int size; 192 unsigned int bytes_read = 0; 193 194 config.channels = channels; 195 config.rate = rate; 196 config.period_size = period_size; 197 config.period_count = period_count; 198 config.format = format; 199 config.start_threshold = 0; 200 config.stop_threshold = 0; 201 config.silence_threshold = 0; 202 203 pcm = pcm_open(card, device, PCM_IN, &config); 204 if (!pcm || !pcm_is_ready(pcm)) { 205 fprintf(stderr, "Unable to open PCM device (%s)\n", 206 pcm_get_error(pcm)); 207 return 0; 208 } 209 210 size = pcm_frames_to_bytes(pcm, pcm_get_buffer_size(pcm)); 211 buffer = malloc(size); 212 if (!buffer) { 213 fprintf(stderr, "Unable to allocate %d bytes\n", size); 214 free(buffer); 215 pcm_close(pcm); 216 return 0; 217 } 218 219 printf("Capturing sample: %u ch, %u hz, %u bit\n", channels, rate, 220 pcm_format_to_bits(format)); 221 222 while (capturing && !pcm_read(pcm, buffer, size)) { 223 if (fwrite(buffer, 1, size, file) != size) { 224 fprintf(stderr,"Error capturing sample\n"); 225 break; 226 } 227 bytes_read += size; 228 } 229 230 free(buffer); 231 pcm_close(pcm); 232 return pcm_bytes_to_frames(pcm, bytes_read); 233 } 234 235
