diff options
Diffstat (limited to 'gst/filter')
| -rw-r--r-- | gst/filter/gstlpwsinc.c | 260 | ||||
| -rw-r--r-- | gst/filter/gstlpwsinc.h | 13 |
2 files changed, 170 insertions, 103 deletions
diff --git a/gst/filter/gstlpwsinc.c b/gst/filter/gstlpwsinc.c index 98a2e4dd..1a34f145 100644 --- a/gst/filter/gstlpwsinc.c +++ b/gst/filter/gstlpwsinc.c @@ -3,6 +3,7 @@ * GStreamer * Copyright (C) 1999-2001 Erik Walthinsen <omega@cse.ogi.edu> * 2006 Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net> + * 2007 Sebastian Dröge <slomo@circular-chaos.org> * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public @@ -25,9 +26,9 @@ * chapter 16 * available at http://www.dspguide.com/ * - * FIXME: - * - this filter is totally unoptimized ! - * - this might be improved upon with bytestream + * TODO: - Implement the convolution in place + * - Implement a highpass mode (spectral inversion) + * - Allow choosing between different windows (blackman, hanning, ...) */ #ifdef HAVE_CONFIG_H @@ -51,7 +52,8 @@ GST_ELEMENT_DETAILS ("Low-pass Windowed sinc filter", "Low-pass Windowed sinc filter", "Thomas <thomas@apestaart.org>, " "Steven W. Smith, " - "Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>"); + "Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>, " + "Sebastian Dröge <slomo@circular-chaos.org>"); /* Filter signals and args */ enum @@ -69,7 +71,7 @@ enum #define ALLOWED_CAPS \ "audio/x-raw-float," \ - " width = (int) 32, " \ + " width = (int) { 32, 64 }, " \ " endianness = (int) BYTE_ORDER," \ " rate = (int) [ 1, MAX ]," \ " channels = (int) [ 1, MAX ]" @@ -85,8 +87,10 @@ static void lpwsinc_set_property (GObject * object, guint prop_id, static void lpwsinc_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); -static GstFlowReturn lpwsinc_transform_ip (GstBaseTransform * base, - GstBuffer * outbuf); +static GstFlowReturn lpwsinc_transform (GstBaseTransform * base, + GstBuffer * inbuf, GstBuffer * outbuf); +static gboolean lpwsinc_get_unit_size (GstBaseTransform * base, GstCaps * caps, + guint * size); static gboolean lpwsinc_setup (GstAudioFilter * base, GstRingBufferSpec * format); @@ -95,16 +99,16 @@ static gboolean lpwsinc_setup (GstAudioFilter * base, static void gst_lpwsinc_dispose (GObject * object) { - GstLPWSinc *this = GST_LPWSINC (object); + GstLPWSinc *self = GST_LPWSINC (object); - if (this->residue) { - g_free (this->residue); - this->residue = NULL; + if (self->residue) { + g_free (self->residue); + self->residue = NULL; } - if (this->kernel) { - g_free (this->kernel); - this->kernel = NULL; + if (self->kernel) { + g_free (self->kernel); + self->kernel = NULL; } G_OBJECT_CLASS (parent_class)->dispose (object); @@ -139,90 +143,172 @@ gst_lpwsinc_class_init (GstLPWSincClass * klass) g_object_class_install_property (gobject_class, PROP_FREQUENCY, g_param_spec_double ("frequency", "Frequency", - "Cut-off Frequency relative to sample rate", - 0.0, 0.5, 0, G_PARAM_READWRITE)); + "Cut-off Frequency", 0.0, G_MAXDOUBLE, 0.0, G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, PROP_LENGTH, g_param_spec_int ("length", "Length", "N such that the filter length = 2N + 1", 1, G_MAXINT, 1, G_PARAM_READWRITE)); - trans_class->transform_ip = GST_DEBUG_FUNCPTR (lpwsinc_transform_ip); + trans_class->transform = GST_DEBUG_FUNCPTR (lpwsinc_transform); + trans_class->get_unit_size = GST_DEBUG_FUNCPTR (lpwsinc_get_unit_size); GST_AUDIO_FILTER_CLASS (klass)->setup = GST_DEBUG_FUNCPTR (lpwsinc_setup); } static void -gst_lpwsinc_init (GstLPWSinc * this, GstLPWSincClass * g_class) +gst_lpwsinc_init (GstLPWSinc * self, GstLPWSincClass * g_class) { - this->wing_size = 50; - this->frequency = 0.25; - this->kernel = NULL; - this->residue = NULL; + self->wing_size = 50; + self->frequency = 0.0; + self->kernel = NULL; + self->residue = NULL; + + self->have_kernel = FALSE; } +static void +process_32 (GstLPWSinc * self, gfloat * src, gfloat * dst, guint input_samples) +{ + gint kernel_length = self->wing_size * 2 + 1;; + gint i, j; -/* GstAudioFilter vmethod implementations */ + /* convolution */ + for (i = 0; i < input_samples; ++i) { + dst[i] = 0.0; + for (j = 0; j < kernel_length; ++j) + if (i < j) + dst[i] += self->residue[kernel_length + i - j] * self->kernel[j]; + else + dst[i] += src[i - j] * self->kernel[j]; + } -/* get notified of caps and plug in the correct process function */ -static gboolean -lpwsinc_setup (GstAudioFilter * base, GstRingBufferSpec * format) + /* copy the tail of the current input buffer to the residue */ + for (i = 0; i < kernel_length; i++) + self->residue[i] = src[input_samples - kernel_length + i]; +} + +static void +process_64 (GstLPWSinc * self, gdouble * src, gdouble * dst, + guint input_samples) +{ + gint kernel_length = self->wing_size * 2 + 1;; + gint i, j; + + /* convolution */ + for (i = 0; i < input_samples; ++i) { + dst[i] = 0.0; + for (j = 0; j < kernel_length; ++j) + if (i < j) + dst[i] += self->residue[kernel_length + i - j] * self->kernel[j]; + else + dst[i] += src[i - j] * self->kernel[j]; + } + + /* copy the tail of the current input buffer to the residue */ + for (i = 0; i < kernel_length; i++) + self->residue[i] = src[input_samples - kernel_length + i]; +} + +static void +lpwsinc_build_kernel (GstLPWSinc * self) { - int i = 0; - double sum = 0.0; - int len = 0; - GstLPWSinc *this = GST_LPWSINC (base); + gint i = 0; + gdouble sum = 0.0; + gint len = 0; + gdouble w; - /* FIXME: remember to free it */ /* fill the kernel */ - g_print ("DEBUG: initing filter kernel\n"); - len = this->wing_size; + len = self->wing_size; GST_DEBUG ("lpwsinc: initializing filter kernel of length %d", len * 2 + 1); - if (this->kernel) - g_free (this->kernel); - this->kernel = (double *) g_malloc (sizeof (double) * (2 * len + 1)); + if (GST_AUDIO_FILTER (self)->format.rate == 0) { + GST_DEBUG ("rate not set yet"); + return; + } + + /* Clamp cutoff frequency between 0 and the nyquist frequency */ + self->frequency = + CLAMP (self->frequency, 0.0, GST_AUDIO_FILTER (self)->format.rate / 2); + + w = 2 * M_PI * (self->frequency / GST_AUDIO_FILTER (self)->format.rate); + + if (self->kernel) + g_free (self->kernel); + self->kernel = g_new (gdouble, 2 * len + 1); for (i = 0; i <= len * 2; ++i) { if (i == len) - this->kernel[i] = 2 * M_PI * this->frequency; + self->kernel[i] = w; else - this->kernel[i] = - sin (2 * M_PI * this->frequency * (i - len)) / (i - len); + self->kernel[i] = sin (w * (i - len)) / (i - len); /* windowing */ - this->kernel[i] *= (0.54 - 0.46 * cos (M_PI * i / len)); + self->kernel[i] *= (0.54 - 0.46 * cos (M_PI * i / len)); } - /* normalize for unity gain at DC - * FIXME: sure this is not supposed to be quadratic ? */ + /* normalize for unity gain at DC */ for (i = 0; i <= len * 2; ++i) - sum += this->kernel[i]; + sum += self->kernel[i]; for (i = 0; i <= len * 2; ++i) - this->kernel[i] /= sum; + self->kernel[i] /= sum; /* set up the residue memory space */ - if (this->residue) - g_free (this->residue); - this->residue = (gfloat *) g_malloc (sizeof (gfloat) * (len * 2 + 1)); - for (i = 0; i <= len * 2; ++i) - this->residue[i] = 0.0; + if (self->residue) + g_free (self->residue); + self->residue = g_new0 (gdouble, len * 2 + 1); + + self->have_kernel = TRUE; +} + +/* GstAudioFilter vmethod implementations */ + +/* get notified of caps and plug in the correct process function */ +static gboolean +lpwsinc_setup (GstAudioFilter * base, GstRingBufferSpec * format) +{ + GstLPWSinc *self = GST_LPWSINC (base); + + gboolean ret = TRUE; + + if (format->width == 32) + self->process = (GstLPWSincProcessFunc) process_32; + else if (format->width == 64) + self->process = (GstLPWSincProcessFunc) process_64; + else + ret = FALSE; + + self->have_kernel = FALSE; return TRUE; } /* GstBaseTransform vmethod implementations */ +static gboolean +lpwsinc_get_unit_size (GstBaseTransform * base, GstCaps * caps, guint * size) +{ + gint width, channels; + GstStructure *structure; + gboolean ret; + + g_assert (size); + + structure = gst_caps_get_structure (caps, 0); + ret = gst_structure_get_int (structure, "width", &width); + ret &= gst_structure_get_int (structure, "channels", &channels); + + *size = width * channels / 8; + + return ret; +} + static GstFlowReturn -lpwsinc_transform_ip (GstBaseTransform * base, GstBuffer * outbuf) +lpwsinc_transform (GstBaseTransform * base, GstBuffer * inbuf, + GstBuffer * outbuf) { - GstLPWSinc *this = GST_LPWSINC (base); + GstLPWSinc *self = GST_LPWSINC (base); GstClockTime timestamp; - - gfloat *src; - gfloat *input; - int residue_samples; - gint input_samples; - gint total_samples; - int i, j; + gint input_samples = + GST_BUFFER_SIZE (outbuf) / (GST_AUDIO_FILTER (self)->format.width / 8); /* don't process data in passthrough-mode */ if (gst_base_transform_is_passthrough (base)) @@ -230,42 +316,14 @@ lpwsinc_transform_ip (GstBaseTransform * base, GstBuffer * outbuf) /* FIXME: subdivide GST_BUFFER_SIZE into small chunks for smooth fades */ timestamp = GST_BUFFER_TIMESTAMP (outbuf); - if (GST_CLOCK_TIME_IS_VALID (timestamp)) - gst_object_sync_values (G_OBJECT (this), timestamp); - - /* FIXME: out of laziness, we copy the left-over bit from last buffer - * together with the incoming buffer to a new buffer to make the loop - * easy; this could be a lot more optimized though - * to make amends we keep the incoming buffer around and write our - * output samples there */ - - src = (gfloat *) GST_BUFFER_DATA (outbuf); - residue_samples = this->wing_size * 2 + 1; - input_samples = GST_BUFFER_SIZE (outbuf) / sizeof (gfloat); - total_samples = residue_samples + input_samples; + gst_object_sync_values (G_OBJECT (self), timestamp); - input = (gfloat *) g_malloc (sizeof (gfloat) * total_samples); - - /* copy the left-over bit */ - memcpy (input, this->residue, sizeof (gfloat) * residue_samples); - - /* copy the new buffer */ - memcpy (&input[residue_samples], src, sizeof (gfloat) * input_samples); - /* copy the tail of the current input buffer to the residue */ - memcpy (this->residue, &src[input_samples - residue_samples], - sizeof (gfloat) * residue_samples); - - /* convolution */ - /* since we copied the previous set of samples we needed before the actual - * input data, we need to add the filter length to our indices for input */ - for (i = 0; i < input_samples; ++i) { - src[i] = 0.0; - for (j = 0; j < residue_samples; ++j) - src[i] += input[i - j + residue_samples] * this->kernel[j]; - } + if (!self->have_kernel) + lpwsinc_build_kernel (self); - g_free (input); + self->process (self, GST_BUFFER_DATA (inbuf), GST_BUFFER_DATA (outbuf), + input_samples); return GST_FLOW_OK; } @@ -274,16 +332,22 @@ static void lpwsinc_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { - GstLPWSinc *this = GST_LPWSINC (object); + GstLPWSinc *self = GST_LPWSINC (object); - g_return_if_fail (GST_IS_LPWSINC (this)); + g_return_if_fail (GST_IS_LPWSINC (self)); switch (prop_id) { case PROP_LENGTH: - this->wing_size = g_value_get_int (value); + GST_BASE_TRANSFORM_LOCK (self); + self->wing_size = g_value_get_int (value); + lpwsinc_build_kernel (self); + GST_BASE_TRANSFORM_UNLOCK (self); break; case PROP_FREQUENCY: - this->frequency = g_value_get_double (value); + GST_BASE_TRANSFORM_LOCK (self); + self->frequency = g_value_get_double (value); + lpwsinc_build_kernel (self); + GST_BASE_TRANSFORM_UNLOCK (self); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); @@ -295,14 +359,14 @@ static void lpwsinc_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { - GstLPWSinc *this = GST_LPWSINC (object); + GstLPWSinc *self = GST_LPWSINC (object); switch (prop_id) { case PROP_LENGTH: - g_value_set_int (value, this->wing_size); + g_value_set_int (value, self->wing_size); break; case PROP_FREQUENCY: - g_value_set_double (value, this->frequency); + g_value_set_double (value, self->frequency); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); diff --git a/gst/filter/gstlpwsinc.h b/gst/filter/gstlpwsinc.h index 14791b51..afb7e9c7 100644 --- a/gst/filter/gstlpwsinc.h +++ b/gst/filter/gstlpwsinc.h @@ -54,6 +54,8 @@ G_BEGIN_DECLS typedef struct _GstLPWSinc GstLPWSinc; typedef struct _GstLPWSincClass GstLPWSincClass; +typedef void (*GstLPWSincProcessFunc) (GstLPWSinc *, guint8 *, guint8 *, guint); + /** * GstLPWSinc: * @@ -62,14 +64,15 @@ typedef struct _GstLPWSincClass GstLPWSincClass; struct _GstLPWSinc { GstAudioFilter element; - void (*process)(GstLPWSinc*, gpointer, gint); + GstLPWSincProcessFunc process; - double frequency; - int wing_size; /* length of a "wing" of the filter; + gdouble frequency; + gint wing_size; /* length of a "wing" of the filter; actual length is 2 * wing_size + 1 */ - gfloat *residue; /* buffer for left-over samples from previous buffer */ - double *kernel; + gdouble *residue; /* buffer for left-over samples from previous buffer */ + gdouble *kernel; /* filter kernel */ + gboolean have_kernel; }; struct _GstLPWSincClass { |