commit 0c0f7c29701e7f1ecb20867c244ffa5fc977fa10
parent 9c1a32213b9516a18b20cb75ec46bc4eaa9f3fc3
Author: Alexander Kojevnikov <alexander@kojevnikov.com>
Date: Fri, 2 Jul 2010 22:06:58 +1000
Add FFTW bindings, use it in the pipeline
Diffstat:
9 files changed, 151 insertions(+), 5 deletions(-)
diff --git a/.gitignore b/.gitignore
@@ -29,6 +29,7 @@ po/stamp-it
samples/
src/*.c
!src/spek-audio.c
+!src/spek-fft.c
src/*.o
src/*.stamp
src/spek
diff --git a/configure.ac b/configure.ac
@@ -24,11 +24,12 @@ AM_PROG_VALAC([0.7.0])
AC_PROG_INSTALL
AC_PROG_INTLTOOL([0.35])
-pkg_modules="gtk+-2.0 >= 2.14.0 gstreamer-0.10 >= 0.10.17 libavformat libavcodec"
-SPEK_PACKAGES="--pkg gtk+-2.0 --pkg gstreamer-0.10"
+pkg_modules="gtk+-2.0 >= 2.14.0 gstreamer-0.10 >= 0.10.17 libavformat libavcodec fftw3f"
PKG_CHECK_MODULES(SPEK, [$pkg_modules])
AC_SUBST(SPEK_CFLAGS)
AC_SUBST(SPEK_LIBS)
+
+SPEK_PACKAGES="--pkg gtk+-2.0 --pkg gstreamer-0.10"
AC_SUBST(SPEK_PACKAGES)
AC_CHECK_LIB(m, log10f)
diff --git a/src/Makefile.am b/src/Makefile.am
@@ -3,6 +3,7 @@ bin_PROGRAMS = spek
spek_SOURCES = \
spek.vala \
spek-audio.c \
+ spek-fft.c \
spek-pipeline.vala \
spek-ruler.vala \
spek-source.vala \
@@ -21,6 +22,7 @@ VALAFLAGS = \
--vapidir=$(srcdir)/../vapi \
--pkg config \
--pkg spek-audio \
+ --pkg spek-fft \
@SPEK_PACKAGES@
spek_LDADD = \
@@ -28,4 +30,5 @@ spek_LDADD = \
$(IGE_MAC_LIBS)
EXTRA_DIST = \
- spek-audio.h
+ spek-audio.h \
+ spek-fft.h
diff --git a/src/spek-fft.c b/src/spek-fft.c
@@ -0,0 +1,55 @@
+/* spek-fft.c
+ *
+ * Copyright (C) 2010 Alexander Kojevnikov <alexander@kojevnikov.com>
+ *
+ * Spek is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Spek is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Spek. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <math.h>
+
+#include "spek-fft.h"
+
+SpekFftPlan * spek_fft_plan_new (gint n) {
+ SpekFftPlan *p = g_new0 (SpekFftPlan, 1);
+ p->input = (gfloat *) fftwf_malloc (sizeof (gfloat) * n);
+ p->output = (gfloat *) fftwf_malloc (sizeof (gfloat) * (n / 2 + 1));
+ p->result = (fftwf_complex *) fftwf_malloc (sizeof (fftwf_complex) * (n / 2 + 1));
+ p->n = n;
+ p->plan = fftwf_plan_dft_r2c_1d (n, p->input, p->result, FFTW_ESTIMATE);
+ return p;
+}
+
+void spek_fft_execute (SpekFftPlan *p) {
+ int i;
+ int bands = p->n / 2 + 1;
+
+ fftwf_execute (p->plan);
+
+ /* Calculate magnitudes */
+ for (i = 0; i < bands; i++) {
+ gfloat val;
+ val = p->result[i][0] * p->result[i][0] + p->result[i][1] * p->result[i][1];
+ val /= p->n * p->n;
+ val = 10.0 * log10f (val);
+ p->output[i] = val;
+ }
+}
+
+void spek_fft_destroy (SpekFftPlan *p) {
+ fftwf_destroy_plan (p->plan);
+ fftwf_free (p->result);
+ fftwf_free (p->output);
+ fftwf_free (p->input);
+ g_free (p);
+}
diff --git a/src/spek-fft.h b/src/spek-fft.h
@@ -0,0 +1,45 @@
+/* spek-fft.h
+ *
+ * Copyright (C) 2010 Alexander Kojevnikov <alexander@kojevnikov.com>
+ *
+ * Spek is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Spek is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Spek. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __SPEK_FFT_H__
+#define __SPEK_FFT_H__
+
+#include <glib.h>
+#include <fftw3.h>
+
+typedef struct {
+ /* Internal data */
+ fftwf_plan plan;
+ gint n;
+ fftwf_complex *result;
+
+ /* Exposed properties */
+ gfloat *input;
+ gfloat *output;
+} SpekFftPlan;
+
+/* Allocate buffers and create a new FFT plan */
+SpekFftPlan * spek_fft_plan_new (gint n);
+
+/* Execute the FFT on plan->input */
+void spek_fft_execute (SpekFftPlan *p);
+
+/* Destroy the plan and de-allocate buffers */
+void spek_fft_destroy (SpekFftPlan *p);
+
+#endif
diff --git a/src/spek-pipeline.vala b/src/spek-pipeline.vala
@@ -77,9 +77,13 @@ namespace Spek {
public void start () {
int nfft = 2 * bands - 2;
var input = new float[nfft];
+ var output = new float[bands];
int pos = 0;
int frames = 0;
int size;
+ // TODO: make it a static class variable and experiment with FFTW_MEASURE.
+ var fft = new Fft.Plan (nfft);
+
while ((size = cx.read (this.buffer)) > 0) {
uint8 *buffer = (uint8 *) this.buffer;
var block_size = cx.width * cx.channels;
@@ -90,7 +94,26 @@ namespace Spek {
pos = (pos + 1) % nfft;
frames++;
- // TODO
+ // If we have enough frames for an FFT or we
+ // have all frames required for the interval run
+ // an FFT. In the last case we probably take the
+ // FFT of frames that we already handled.
+ if (frames % nfft == 0
+ // TODO: error correction
+// || ((spectrum->accumulated_error < GST_SECOND
+// && spectrum->num_frames == spectrum->frames_per_interval)
+// ||
+// (spectrum->accumulated_error >= GST_SECOND
+// && spectrum->num_frames - 1 == spectrum->frames_per_interval))
+ ) {
+ for (int i = 0; i < nfft; i++) {
+ fft.input[i] = input[(pos + i) % nfft];
+ }
+ fft.execute ();
+ for (int i = 0; i < bands; i++) {
+ output[i] += fft.output[i];
+ }
+ }
}
assert (size == 0);
}
diff --git a/src/spek-spectrogram.vala b/src/spek-spectrogram.vala
@@ -91,6 +91,7 @@ namespace Spek {
// TODO
var pipeline = new Pipeline (file_name, BANDS, samples, THRESHOLD, data_cb);
+ pipeline.start ();
print ("\n%s:\n%s\n", file_name, pipeline.description);
queue_draw ();
diff --git a/vapi/Makefile.am b/vapi/Makefile.am
@@ -1,6 +1,7 @@
noinst_DATA = \
config.vapi \
- spek-audio.vapi
+ spek-audio.vapi \
+ spek-fft.vapi
EXTRA_DIST = \
$(noinst_DATA)
diff --git a/vapi/spek-fft.vapi b/vapi/spek-fft.vapi
@@ -0,0 +1,16 @@
+[CCode (cprefix = "SpekFft", lower_case_cprefix = "spek_fft_", cheader_filename = "spek-fft.h")]
+namespace Spek.Fft {
+ [Compact]
+ [CCode (free_function = "spek_fft_destroy")]
+ public class Plan {
+ [CCode (array_length = false)]
+ public unowned float[] input;
+ [CCode (array_length = false)]
+ public unowned float[] output;
+
+ [CCode (cname = "spek_fft_plan_new")]
+ public Plan (int n);
+ [CCode (cname = "spek_fft_execute")]
+ public void execute ();
+ }
+}
