Move timefilter code from lavf to lavd.

It's only used in the JACK device.

Fixes linking shared lavd with JACK enabled.

4 files changed, 252 insertions, 2 deletions

diff --git a/libavdevice/Makefile b/libavdevice/Makefile
index d8a5945549..1f2a6efceb 100644
--- a/libavdevice/Makefile
+++ b/libavdevice/Makefile
@@ -13,7 +13,7 @@ OBJS-$(CONFIG_ALSA_OUTDEV)               += alsa-audio-common.o \
 OBJS-$(CONFIG_BKTR_INDEV)                += bktr.o
 OBJS-$(CONFIG_DV1394_INDEV)              += dv1394.o
 OBJS-$(CONFIG_FBDEV_INDEV)               += fbdev.o
-OBJS-$(CONFIG_JACK_INDEV)                += jack_audio.o
+OBJS-$(CONFIG_JACK_INDEV)                += jack_audio.o timefilter.o
 OBJS-$(CONFIG_OSS_INDEV)                 += oss_audio.o
 OBJS-$(CONFIG_OSS_OUTDEV)                += oss_audio.o
 OBJS-$(CONFIG_SNDIO_INDEV)               += sndio_common.o sndio_dec.o
@@ -30,4 +30,6 @@ OBJS-$(CONFIG_LIBDC1394_INDEV)           += libdc1394.o
 SKIPHEADERS-$(HAVE_ALSA_ASOUNDLIB_H)     += alsa-audio.h
 SKIPHEADERS-$(HAVE_SNDIO_H)              += sndio_common.h
 
+TESTPROGS = timefilter
+
 include $(SRC_PATH)/subdir.mak
diff --git a/libavdevice/jack_audio.c b/libavdevice/jack_audio.c
index 4907e82395..f75c176be9 100644
--- a/libavdevice/jack_audio.c
+++ b/libavdevice/jack_audio.c
@@ -29,7 +29,7 @@
 #include "libavutil/opt.h"
 #include "libavcodec/avcodec.h"
 #include "libavformat/avformat.h"
-#include "libavformat/timefilter.h"
+#include "timefilter.h"
 
 /**
  * Size of the internal FIFO buffers as a number of audio packets
diff --git a/libavdevice/timefilter.c b/libavdevice/timefilter.c
new file mode 100644
index 0000000000..332d33b5e8
--- /dev/null
+++ b/libavdevice/timefilter.c
@@ -0,0 +1,151 @@
+/*
+ * Delay Locked Loop based time filter
+ * Copyright (c) 2009 Samalyse
+ * Copyright (c) 2009 Michael Niedermayer
+ * Author: Olivier Guilyardi <olivier samalyse com>
+ *         Michael Niedermayer <michaelni gmx at>
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+
+#include "config.h"
+#include "timefilter.h"
+#include "libavutil/mem.h"
+
+struct TimeFilter {
+    /// Delay Locked Loop data. These variables refer to mathematical
+    /// concepts described in: http://www.kokkinizita.net/papers/usingdll.pdf
+    double cycle_time;
+    double feedback2_factor;
+    double feedback3_factor;
+    double clock_period;
+    int count;
+};
+
+TimeFilter * ff_timefilter_new(double clock_period, double feedback2_factor, double feedback3_factor)
+{
+    TimeFilter *self        = av_mallocz(sizeof(TimeFilter));
+    self->clock_period      = clock_period;
+    self->feedback2_factor  = feedback2_factor;
+    self->feedback3_factor  = feedback3_factor;
+    return self;
+}
+
+void ff_timefilter_destroy(TimeFilter *self)
+{
+    av_freep(&self);
+}
+
+void ff_timefilter_reset(TimeFilter *self)
+{
+    self->count      = 0;
+}
+
+double ff_timefilter_update(TimeFilter *self, double system_time, double period)
+{
+    self->count++;
+    if (self->count==1) {
+        /// init loop
+        self->cycle_time    = system_time;
+    } else {
+        double loop_error;
+        self->cycle_time   += self->clock_period * period;
+        /// calculate loop error
+        loop_error          = system_time - self->cycle_time;
+
+        /// update loop
+        self->cycle_time   += FFMAX(self->feedback2_factor, 1.0/(self->count)) * loop_error;
+        self->clock_period += self->feedback3_factor * loop_error / period;
+    }
+    return self->cycle_time;
+}
+
+#ifdef TEST
+#include "libavutil/lfg.h"
+#define LFG_MAX ((1LL << 32) - 1)
+
+#undef printf
+
+int main(void)
+{
+    AVLFG prng;
+    double n0,n1;
+#define SAMPLES 1000
+    double ideal[SAMPLES];
+    double samples[SAMPLES];
+#if 1
+    for(n0= 0; n0<40; n0=2*n0+1){
+        for(n1= 0; n1<10; n1=2*n1+1){
+#else
+    {{
+        n0=7;
+        n1=1;
+#endif
+            double best_error= 1000000000;
+            double bestpar0=1;
+            double bestpar1=0.001;
+            int better, i;
+
+            av_lfg_init(&prng, 123);
+            for(i=0; i<SAMPLES; i++){
+                ideal[i]  = 10 + i + n1*i/(1000);
+                samples[i] = ideal[i] + n0 * (av_lfg_get(&prng) - LFG_MAX / 2)
+                                           / (LFG_MAX * 10LL);
+            }
+
+            do{
+                double par0, par1;
+                better=0;
+                for(par0= bestpar0*0.8; par0<=bestpar0*1.21; par0+=bestpar0*0.05){
+                    for(par1= bestpar1*0.8; par1<=bestpar1*1.21; par1+=bestpar1*0.05){
+                        double error=0;
+                        TimeFilter *tf= ff_timefilter_new(1, par0, par1);
+                        for(i=0; i<SAMPLES; i++){
+                            double filtered;
+                            filtered=  ff_timefilter_update(tf, samples[i], 1);
+                            error += (filtered - ideal[i]) * (filtered - ideal[i]);
+                        }
+                        ff_timefilter_destroy(tf);
+                        if(error < best_error){
+                            best_error= error;
+                            bestpar0= par0;
+                            bestpar1= par1;
+                            better=1;
+                        }
+                    }
+                }
+            }while(better);
+#if 0
+            double lastfil=9;
+            TimeFilter *tf= ff_timefilter_new(1, bestpar0, bestpar1);
+            for(i=0; i<SAMPLES; i++){
+                double filtered;
+                filtered=  ff_timefilter_update(tf, samples[i], 1);
+                printf("%f %f %f %f\n", i - samples[i] + 10, filtered - samples[i], samples[FFMAX(i, 1)] - samples[FFMAX(i-1, 0)], filtered - lastfil);
+                lastfil= filtered;
+            }
+            ff_timefilter_destroy(tf);
+#else
+            printf(" [%f %f %9f]", bestpar0, bestpar1, best_error);
+#endif
+        }
+        printf("\n");
+    }
+    return 0;
+}
+#endif
diff --git a/libavdevice/timefilter.h b/libavdevice/timefilter.h
new file mode 100644
index 0000000000..c98fd03bba
--- /dev/null
+++ b/libavdevice/timefilter.h
@@ -0,0 +1,97 @@
+/*
+ * Delay Locked Loop based time filter prototypes and declarations
+ * Copyright (c) 2009 Samalyse
+ * Copyright (c) 2009 Michael Niedermayer
+ * Author: Olivier Guilyardi <olivier samalyse com>
+ *         Michael Niedermayer <michaelni gmx at>
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVDEVICE_TIMEFILTER_H
+#define AVDEVICE_TIMEFILTER_H
+
+/**
+ * Opaque type representing a time filter state
+ *
+ * The purpose of this filter is to provide a way to compute accurate time
+ * stamps that can be compared to wall clock time, especially when dealing
+ * with two clocks: the system clock and a hardware device clock, such as
+ * a soundcard.
+ */
+typedef struct TimeFilter TimeFilter;
+
+
+/**
+ * Create a new Delay Locked Loop time filter
+ *
+ * feedback2_factor and feedback3_factor are the factors used for the
+ * multiplications that are respectively performed in the second and third
+ * feedback paths of the loop.
+ *
+ * Unless you know what you are doing, you should set these as follow:
+ *
+ * o = 2 * M_PI * bandwidth * period
+ * feedback2_factor = sqrt(2 * o)
+ * feedback3_factor = o * o
+ *
+ * Where bandwidth is up to you to choose. Smaller values will filter out more
+ * of the jitter, but also take a longer time for the loop to settle. A good
+ * starting point is something between 0.3 and 3 Hz.
+ *
+ * @param clock_period period of the hardware clock in seconds
+ *        (for example 1.0/44100)
+ *
+ * For more details about these parameters and background concepts please see:
+ * http://www.kokkinizita.net/papers/usingdll.pdf
+ */
+TimeFilter * ff_timefilter_new(double clock_period, double feedback2_factor, double feedback3_factor);
+
+/**
+ * Update the filter
+ *
+ * This function must be called in real time, at each process cycle.
+ *
+ * @param period the device cycle duration in clock_periods. For example, at
+ * 44.1kHz and a buffer size of 512 frames, period = 512 when clock_period
+ * was 1.0/44100, or 512/44100 if clock_period was 1.
+ *
+ * system_time, in seconds, should be the value of the system clock time,
+ * at (or as close as possible to) the moment the device hardware interrupt
+ * occured (or any other event the device clock raises at the beginning of a
+ * cycle).
+ *
+ * @return the filtered time, in seconds
+ */
+double ff_timefilter_update(TimeFilter *self, double system_time, double period);
+
+/**
+ * Reset the filter
+ *
+ * This function should mainly be called in case of XRUN.
+ *
+ * Warning: after calling this, the filter is in an undetermined state until
+ * the next call to ff_timefilter_update()
+ */
+void ff_timefilter_reset(TimeFilter *);
+
+/**
+ * Free all resources associated with the filter
+ */
+void ff_timefilter_destroy(TimeFilter *);
+
+#endif /* AVDEVICE_TIMEFILTER_H */