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Author: dim13

alsa.c

@@ -31,6 +31,11 @@ static snd_pcm_hw_params_t *par;
 static int16_t *buffer;
 static unsigned int samples;
 
+struct data {
+	int16_t left;
+	int16_t right;
+};
+
 int
 init_sio(void)
 {
@@ -76,10 +81,12 @@ max_samples_sio(void)
 	return samples;
 }
 
-int16_t *
-read_sio(size_t n)
+void
+read_sio(double *left, double *right, size_t n)
 {
 	snd_pcm_sframes_t rc;
+	struct data *data;
+	int i;
 
 	if (n > samples)
 		n = samples;
@@ -91,7 +98,12 @@ read_sio(size_t n)
 			snd_pcm_prepare(hdl);
 	}
 
-	return buffer + samples - n;
+	data = (struct data *)&buffer[samples - n];
+
+	for (i = 0; i < n; i++) {
+		left[i] = data[i].left;
+		right[i] = data[i].right;
+	}
 }
 
 void

fft.c

@@ -84,17 +84,17 @@ init_fft(size_t n)
 }
 
 int
-exec_fft(int16_t *data, double *out, enum fft_chan chan)
+exec_fft(double *io)
 {
 	int	i;
 
 	for (i = 0; i < fft.n; i++)
-		fft.in[i] = fft.window[i] * data[2 * i + chan];
+		fft.in[i] = fft.window[i] * io[i];
 
 	fftw_execute(fft.plan);
 
 	for (i = 0; i < fft.n / 2; i++)
-		out[i] = fft.sq[i] * cabs(fft.out[i]);
+		io[i] = fft.sq[i] * cabs(fft.out[i]);
 
 	return 0;
 }

fft.h

@@ -18,11 +18,9 @@
 #ifndef __FFT_H
 #define __FFT_H
 
-enum fft_chan { FFT_LEFT, FFT_RIGHT };
-
 __BEGIN_DECLS
 int init_fft(size_t);
-int exec_fft(int16_t *, double *, enum fft_chan);
+int exec_fft(double *);
 void free_fft(void);
 __END_DECLS
 

sio.c

@@ -32,6 +32,11 @@ static struct	sio_par par;
 static int16_t	*buffer;
 static unsigned int samples;
 
+struct data {
+	int16_t left;
+	int16_t right;
+};
+
 int
 init_sio(void)
 {
@@ -78,13 +83,14 @@ max_samples_sio(void)
 	return samples;
 }
 
-int16_t *
-read_sio(size_t n)
+void
+read_sio(double *left, double *right, size_t n)
 {
-	int done;
+	int done, i;
 	char *p = (char *)buffer;
 	size_t bufsz = samples * par.rchan * sizeof(int16_t);
 	size_t rndsz = n * par.rchan * sizeof(int16_t);
+	struct data *data;
 
 	if (rndsz > bufsz)
 		rndsz = bufsz;
@@ -99,7 +105,12 @@ read_sio(size_t n)
 	 * return a pointer to the latest ROUND samples (the most recent
 	 * ones) to minimize latency between picture and sound
 	 */
-	return (int16_t *)(p - rndsz);
+	data = (struct data *)(p - rndsz);
+
+	for (i = 0; i < n; i++) {
+		left[i] = data[i].left;
+		right[i] = data[i].right;
+	}
 }
 
 void

sio.h

@@ -20,7 +20,7 @@
 
 __BEGIN_DECLS
 int init_sio(void);
-int16_t *read_sio(size_t);
+void read_sio(double *, double *, size_t);
 unsigned int max_samples_sio(void);
 void free_sio(void);
 __END_DECLS

spectrogram.c

@@ -303,7 +303,7 @@ init_panel(Display *d, Window win, XRectangle r, enum mirror m)
 	p = malloc(sizeof(struct panel));
 	assert(p);
 
-	p->data = calloc(r.width, sizeof(double));
+	p->data = calloc(2 * r.width, sizeof(double));
 	assert(p->data);
 
 	/* main panel window */
@@ -449,7 +449,6 @@ main(int argc, char **argv)
 	int		scr;
 
 	struct		panel *left, *right;
-	int16_t		*buffer;
 
 	int		dflag = 0;	/* daemonize */
 	int		fflag = 0;	/* fullscreen */
@@ -607,10 +606,10 @@ main(int argc, char **argv)
 			}
 		}
 
-		buffer = read_sio(round);
+		read_sio(left->data, right->data, round);
 
-		exec_fft(buffer, left->data, FFT_LEFT);
-		exec_fft(buffer, right->data, FFT_RIGHT);
+		exec_fft(left->data);
+		exec_fft(right->data);
 
 		draw_panel(dsp, left);
 		draw_panel(dsp, right);