Add volume optionHEADmaster

4 files changed, 13 insertions, 5 deletions

diff --git a/gtk.c b/gtk.c
index ef10c48..d2fe31c 100644
--- a/gtk.c
+++ b/gtk.c
@@ -37,7 +37,7 @@ gpointer alsa_thread(gpointer data)
         if (running) {
             uint16_t *buffer = NULL;
             size_t size;
-            metronome_generate(&buffer, &size, 48000, bpm, 4, 4, SOUND_SINE);
+            metronome_generate(&buffer, &size, 48000, bpm, 4, 4, SOUND_SINE, 1.0);
             alsa_play(buffer, size);
             free(buffer);
         }
diff --git a/main.c b/main.c
index fc5b79d..54ed1ae 100644
--- a/main.c
+++ b/main.c
@@ -7,6 +7,7 @@
 #include <stdbool.h>
 #include <string.h>
 #include <getopt.h>
+#include <math.h>
 
 #include "metronome.h"
 #include "alsa.h"
@@ -23,6 +24,7 @@ static void usage()
     printf("Options:\n");
     printf("  -o, --output=FILE  export WAV file\n");
     printf("  -s, --sound=SOUND  play sine, square, saw or triangle\n");
+    printf("  -v, --volume       set output volume (0.0 - 1.0)\n");
     printf("  -h, --help         display this help and exit\n");
     printf("  -V, --version      display version information and exit\n");
 }
@@ -33,17 +35,19 @@ int main(int argc, char *argv[])
 
     char *output = NULL;
     Sound sound = SOUND_SINE;
+    float volume = 1.0;
 
     static struct option long_options[] = {
         { "output",  required_argument, NULL, 'o' },
         { "sound",   required_argument, NULL, 's' },
+        { "volume",  required_argument, NULL, 'v' },
         { "help",    no_argument,       NULL, 'h' },
         { "version", no_argument,       NULL, 'V' },
         { NULL,      0,                 NULL, 0 },
     };
 
     int c;
-    while ((c = getopt_long(argc, argv, "o:s:hV", long_options, NULL)) != -1) {
+    while ((c = getopt_long(argc, argv, "o:s:v:hV", long_options, NULL)) != -1) {
         switch (c) {
             case 'o':
                 output = optarg;
@@ -62,6 +66,9 @@ int main(int argc, char *argv[])
                     exit(EXIT_FAILURE);
                 }
                 break;
+            case 'v':
+                volume = powf(atof(optarg), 4);
+                break;
             case 'h':
                 usage();
                 return EXIT_SUCCESS;
@@ -105,7 +112,7 @@ int main(int argc, char *argv[])
 
     uint16_t *buffer = NULL;
     size_t size;
-    metronome_generate(&buffer, &size, sample_rate, tempo, numerator, denominator, sound);
+    metronome_generate(&buffer, &size, sample_rate, tempo, numerator, denominator, sound, volume);
 
     if (output) {
         wav_write(output, sample_rate, buffer, size, 4);
diff --git a/metronome.c b/metronome.c
index 3abd499..4973a00 100644
--- a/metronome.c
+++ b/metronome.c
@@ -17,7 +17,7 @@ static double sgn(double x)
     return 0;
 }
 
-void metronome_generate(uint16_t **buffer, size_t *size, unsigned int sample_rate, long tempo, int numerator, int denominator, Sound sound)
+void metronome_generate(uint16_t **buffer, size_t *size, unsigned int sample_rate, long tempo, int numerator, int denominator, Sound sound, float volume)
 {
     size_t beat = 4 * 60 * sample_rate / tempo / denominator;
     *size = beat * numerator;
@@ -48,6 +48,7 @@ void metronome_generate(uint16_t **buffer, size_t *size, unsigned int sample_rat
                     sample = 4 * fabs(fmod(i * freq / sample_rate - 0.25, 1) - 0.5) - 1;
                     break;
             }
+            sample *= volume;
 
             // Fade sound in and out to reduce audio pops and clicks.
             if (t < 0.1) {
diff --git a/metronome.h b/metronome.h
index 1aa445d..8b2e478 100644
--- a/metronome.h
+++ b/metronome.h
@@ -14,6 +14,6 @@ typedef enum {
     SOUND_TRIANGLE,
 } Sound;
 
-extern void metronome_generate(uint16_t **buffer, size_t *size, unsigned int sample_rate, long tempo, int numerator, int denominator, Sound sound);
+extern void metronome_generate(uint16_t **buffer, size_t *size, unsigned int sample_rate, long tempo, int numerator, int denominator, Sound sound, float volume);
 
 #endif // METRONOME_H