From daa2bf805313d4ba99c24dcd491f27546410ea31 Mon Sep 17 00:00:00 2001 From: Sanchayan Maity Date: Wed, 3 May 2017 14:17:27 +0530 Subject: [PATCH] Add wav file playback code using ALSA --- alsa-audio/.cproject | 64 +++++++++ alsa-audio/.gitignore | 1 + alsa-audio/.project | 26 ++++ alsa-audio/.settings/language.settings.xml | 14 ++ alsa-audio/monowavplayback.c | 151 +++++++++++++++++++++ 5 files changed, 256 insertions(+) create mode 100644 alsa-audio/.cproject create mode 100644 alsa-audio/.gitignore create mode 100644 alsa-audio/.project create mode 100644 alsa-audio/.settings/language.settings.xml create mode 100644 alsa-audio/monowavplayback.c diff --git a/alsa-audio/.cproject b/alsa-audio/.cproject new file mode 100644 index 0000000..2ed9456 --- /dev/null +++ b/alsa-audio/.cproject @@ -0,0 +1,64 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/alsa-audio/.gitignore b/alsa-audio/.gitignore new file mode 100644 index 0000000..3df573f --- /dev/null +++ b/alsa-audio/.gitignore @@ -0,0 +1 @@ +/Debug/ diff --git a/alsa-audio/.project b/alsa-audio/.project new file mode 100644 index 0000000..bb24a38 --- /dev/null +++ b/alsa-audio/.project @@ -0,0 +1,26 @@ + + + alsa-audio + + + + + + org.eclipse.cdt.managedbuilder.core.genmakebuilder + clean,full,incremental, + + + + + org.eclipse.cdt.managedbuilder.core.ScannerConfigBuilder + full,incremental, + + + + + + org.eclipse.cdt.core.cnature + org.eclipse.cdt.managedbuilder.core.managedBuildNature + org.eclipse.cdt.managedbuilder.core.ScannerConfigNature + + diff --git a/alsa-audio/.settings/language.settings.xml b/alsa-audio/.settings/language.settings.xml new file mode 100644 index 0000000..e116f0e --- /dev/null +++ b/alsa-audio/.settings/language.settings.xml @@ -0,0 +1,14 @@ + + + + + + + + + + + + + + diff --git a/alsa-audio/monowavplayback.c b/alsa-audio/monowavplayback.c new file mode 100644 index 0000000..fb81440 --- /dev/null +++ b/alsa-audio/monowavplayback.c @@ -0,0 +1,151 @@ +#include +#include + +static unsigned int rate = 44100; + +int main(int argc, char *argv[]) +{ + FILE *fp; + int dir; + int err; + int size; + long loops; + unsigned int rrate, val; + char *buffer; + char devname[32] = {0}; + snd_pcm_t *handle; + snd_pcm_hw_params_t *params; + snd_pcm_uframes_t frames; + + if (argc < 3) { + printf("Usage: %s \n", argv[0]); + exit(EXIT_FAILURE); + } + + if (argc >= 2) { + fp = fopen(argv[1], "r"); + if (!fp) { + printf("Could not open file %s\n", argv[1]); + exit(EXIT_FAILURE); + } + } + + if (argc == 4) { + rate = atoi(argv[3]); + printf("Requested playback rate: %d\n", rate); + } + + printf("Module Name: %s\n", argv[2]); + + if (!strcmp("colibri-vf", argv[2])) + strcpy(devname, "default:CARD=Audio"); + else if (!strcmp("apalis-imx6", argv[2])) + strcpy(devname, "default:CARD=imx6qapalissgtl"); + else if (!strcmp("colibri-imx6", argv[2])) + strcpy(devname, "default:CARD=imx6qcolibrisgtl"); + else if (!strcmp("colibri-t20", argv[2])) + strcpy(devname, "default:CARD=colibrit20wm971"); + else if (!strcmp("colibri-t30", argv[2])) + strcpy(devname, "default:CARD=colibrit30sgtl5"); + + err = snd_pcm_open(&handle, devname, SND_PCM_STREAM_PLAYBACK, 0); + if (err < 0) { + fprintf(stderr, "unable to open pcm device: %s\n", snd_strerror(err)); + exit(EXIT_FAILURE); + } + + snd_pcm_hw_params_alloca(¶ms); + + err = snd_pcm_hw_params_any(handle, params); + if (err < 0) { + printf("Broken configuration for playback: no configurations available: %s\n", snd_strerror(err)); + return err; + } + + err = snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); + if (err < 0) { + printf("Resampling setup failed for playback: %s\n", snd_strerror(err)); + return err; + } + + err = snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE); + if (err < 0) { + printf("Sample format not available for playback: %s\n", snd_strerror(err)); + return err; + } + + err = snd_pcm_hw_params_set_channels(handle, params, 1); + if (err < 0) { + printf("Channels count (%i) not available for playbacks: %s\n", 1, snd_strerror(err)); + return err; + } + + rrate = rate; + err = snd_pcm_hw_params_set_rate_near(handle, params, &rrate, 0); + if (err < 0) { + printf("Rate %iHz not available for playback: %s\n", rrate, snd_strerror(err)); + return err; + } + + if (rrate != rate) { + printf("Rate doesn't match (requested %iHz, get %iHz)\n", rate, err); + return -EINVAL; + } + + err = snd_pcm_hw_params(handle, params); + if (err < 0) { + fprintf(stderr, "unable to set hw parameters: %s\n", + snd_strerror(err)); + exit(EXIT_FAILURE); + } + + /* Use a buffer large enough to hold one period */ + snd_pcm_hw_params_get_period_size(params, &frames, &dir); + //size = frames * 4; /* 2 bytes/sample, 2 channels */ + size = frames * 2; /* 2 bytes/sample, 1 channel */ + buffer = (char *) malloc(size); + if (!buffer) { + snd_pcm_drain(handle); + snd_pcm_close(handle); + fclose(fp); + return -ENOMEM; + } + + /* We want to loop for 5 seconds */ + err = snd_pcm_hw_params_get_period_time(params, &val, &dir); + if (err < 0) { + printf("Unable to get period time for playback: %s\n", snd_strerror(err)); + return err; + } + + /* 5 seconds in microseconds divided by period time */ + loops = 5000000 / val; + + while (1) { + loops--; + err = fread(buffer, 1, size, fp); + if (err == 0) { + fprintf(stderr, "end of file on input\n"); + break; + } else if (err != size) + fprintf(stderr, "short read: read %d bytes\n", err); + + err = snd_pcm_writei(handle, buffer, frames); + if (err == -EPIPE) { + /* EPIPE means underrun */ + fprintf(stderr, "underrun occurred\n"); + snd_pcm_prepare(handle); + } + else if (err < 0) + fprintf(stderr, "error from writei: %s\n", snd_strerror(err)); + else if (err != (int)frames) + fprintf(stderr, "short write, write %d frames\n", err); + } + + snd_pcm_drain(handle); + snd_pcm_close(handle); + free(buffer); + fclose(fp); + + return 0; +}