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gst/filter/gstlpwsinc.*: Implement latency query and only forward those samples downstream that actually contain the ...

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Original commit message from CVS:
* gst/filter/gstlpwsinc.c: (gst_lpwsinc_class_init),
(gst_lpwsinc_init), (process_32), (process_64),
(lpwsinc_build_kernel), (lpwsinc_push_residue),
(lpwsinc_transform), (lpwsinc_start), (lpwsinc_query),
(lpwsinc_query_type), (lpwsinc_event), (lpwsinc_set_property):
* gst/filter/gstlpwsinc.h:
Implement latency query and only forward those samples downstream
that actually contain the data we want, i.e. drop kernel_length/2
in the beginning and append kernel_length/2 (created by convolving
the filter kernel with zeroes) to the end.
* tests/check/elements/lpwsinc.c: (GST_START_TEST):
Adjust the unit test for this slightly changed behaviour.
This commit is contained in:
Sebastian Dröge 2007-08-16 09:48:27 +00:00
parent 647e2dd7c0
commit a490cffe5f
3 changed files with 357 additions and 54 deletions
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297
gst/audiofx/audiowsinclimit.c
View file

@ -171,9 +171,13 @@ static GstFlowReturn lpwsinc_transform (GstBaseTransform * base,
static gboolean lpwsinc_get_unit_size (GstBaseTransform * base, GstCaps * caps,
guint * size);
static gboolean lpwsinc_start (GstBaseTransform * base);
static gboolean lpwsinc_event (GstBaseTransform * base, GstEvent * event);
static gboolean lpwsinc_setup (GstAudioFilter * base,
GstRingBufferSpec * format);
static gboolean lpwsinc_query (GstPad * pad, GstQuery * query);
static const GstQueryType *lpwsinc_query_type (GstPad * pad);
/* Element class */
static void
@ -246,6 +250,7 @@ gst_lpwsinc_class_init (GstLPWSincClass * klass)
trans_class->transform = GST_DEBUG_FUNCPTR (lpwsinc_transform);
trans_class->get_unit_size = GST_DEBUG_FUNCPTR (lpwsinc_get_unit_size);
trans_class->start = GST_DEBUG_FUNCPTR (lpwsinc_start);
trans_class->event = GST_DEBUG_FUNCPTR (lpwsinc_event);
filter_class->setup = GST_DEBUG_FUNCPTR (lpwsinc_setup);
}
@ -255,11 +260,19 @@ gst_lpwsinc_init (GstLPWSinc * self, GstLPWSincClass * g_class)
self->mode = MODE_LOW_PASS;
self->window = WINDOW_HAMMING;
self->kernel_length = 101;
self->latency = 50;
self->frequency = 0.0;
self->kernel = NULL;
self->residue = NULL;
self->have_kernel = FALSE;
self->residue_length = 0;
self->next_ts = GST_CLOCK_TIME_NONE;
self->next_off = GST_BUFFER_OFFSET_NONE;
gst_pad_set_query_function (GST_BASE_TRANSFORM (self)->srcpad, lpwsinc_query);
gst_pad_set_query_type_function (GST_BASE_TRANSFORM (self)->srcpad,
lpwsinc_query_type);
}
static void
@ -296,6 +309,10 @@ process_32 (GstLPWSinc * self, gfloat * src, gfloat * dst, guint input_samples)
self->residue[i] = self->residue[i + input_samples];
for (i = res_start; i < kernel_length * channels; i++)
self->residue[i] = src[input_samples - kernel_length * channels + i];
self->residue_length += kernel_length * channels - res_start;
if (self->residue_length > kernel_length * channels)
self->residue_length = kernel_length * channels;
}
static void
@ -333,6 +350,10 @@ process_64 (GstLPWSinc * self, gdouble * src, gdouble * dst,
self->residue[i] = self->residue[i + input_samples];
for (i = res_start; i < kernel_length * channels; i++)
self->residue[i] = src[input_samples - kernel_length * channels + i];
self->residue_length += kernel_length * channels - res_start;
if (self->residue_length > kernel_length * channels)
self->residue_length = kernel_length * channels;
}
static void
@ -400,12 +421,88 @@ lpwsinc_build_kernel (GstLPWSinc * self)
}
/* set up the residue memory space */
if (self->residue)
g_free (self->residue);
self->residue =
g_new0 (gdouble, len * GST_AUDIO_FILTER (self)->format.channels);
if (!self->residue)
self->residue =
g_new0 (gdouble, len * GST_AUDIO_FILTER (self)->format.channels);
self->have_kernel = TRUE;
self->residue_length = 0;
}
static void
lpwsinc_push_residue (GstLPWSinc * self)
{
GstBuffer *outbuf;
GstFlowReturn res;
gint rate = GST_AUDIO_FILTER (self)->format.rate;
gint channels = GST_AUDIO_FILTER (self)->format.channels;
gint outsize, outsamples;
gint diffsize, diffsamples;
guint8 *in, *out;
/* Calculate the number of samples and their memory size that
* should be pushed from the residue */
outsamples = MIN (self->latency, self->residue_length / channels);
outsize = outsamples * channels * (GST_AUDIO_FILTER (self)->format.width / 8);
if (outsize == 0)
return;
/* Process the difference between latency and residue_length samples
* to start at the actual data instead of starting at the zeros before
* when we only got one buffer smaller than latency */
diffsamples = self->latency - self->residue_length / channels;
diffsize =
diffsamples * channels * (GST_AUDIO_FILTER (self)->format.width / 8);
if (diffsize > 0) {
in = g_new0 (guint8, diffsize);
out = g_new0 (guint8, diffsize);
self->process (self, in, out, diffsamples * channels);
g_free (in);
g_free (out);
}
res = gst_pad_alloc_buffer (GST_BASE_TRANSFORM (self)->srcpad,
GST_BUFFER_OFFSET_NONE, outsize,
GST_PAD_CAPS (GST_BASE_TRANSFORM (self)->srcpad), &outbuf);
if (G_UNLIKELY (res != GST_FLOW_OK)) {
GST_WARNING_OBJECT (self, "failed allocating buffer of %d bytes", outsize);
return;
}
/* Convolve the residue with zeros to get the actual remaining data */
in = g_new0 (guint8, outsize);
self->process (self, in, GST_BUFFER_DATA (outbuf), outsamples * channels);
g_free (in);
/* Set timestamp, offset, etc from the values we
* saved when processing the regular buffers */
if (GST_CLOCK_TIME_IS_VALID (self->next_ts))
GST_BUFFER_TIMESTAMP (outbuf) = self->next_ts;
else
GST_BUFFER_TIMESTAMP (outbuf) = 0;
GST_BUFFER_DURATION (outbuf) =
gst_util_uint64_scale (outsamples, GST_SECOND, rate);
self->next_ts += gst_util_uint64_scale (outsamples, GST_SECOND, rate);
if (self->next_off != GST_BUFFER_OFFSET_NONE) {
GST_BUFFER_OFFSET (outbuf) = self->next_off;
GST_BUFFER_OFFSET_END (outbuf) = self->next_off + outsamples;
}
GST_DEBUG_OBJECT (self, "Pushing residue buffer of size %d with timestamp: %"
GST_TIME_FORMAT ", duration: %" GST_TIME_FORMAT ", offset: %lld,"
" offset_end: %lld, nsamples: %d", GST_BUFFER_SIZE (outbuf),
GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (outbuf)),
GST_TIME_ARGS (GST_BUFFER_DURATION (outbuf)), GST_BUFFER_OFFSET (outbuf),
GST_BUFFER_OFFSET_END (outbuf), outsamples);
res = gst_pad_push (GST_BASE_TRANSFORM (self)->srcpad, outbuf);
if (G_UNLIKELY (res != GST_FLOW_OK)) {
GST_WARNING_OBJECT (self, "failed to push residue");
}
}
/* GstAudioFilter vmethod implementations */
@ -456,8 +553,12 @@ lpwsinc_transform (GstBaseTransform * base, GstBuffer * inbuf,
{
GstLPWSinc *self = GST_LPWSINC (base);
GstClockTime timestamp;
gint channels = GST_AUDIO_FILTER (self)->format.channels;
gint rate = GST_AUDIO_FILTER (self)->format.rate;
gint input_samples =
GST_BUFFER_SIZE (outbuf) / (GST_AUDIO_FILTER (self)->format.width / 8);
gint output_samples = input_samples;
gint diff;
/* don't process data in passthrough-mode */
if (gst_base_transform_is_passthrough (base))
@ -471,9 +572,100 @@ lpwsinc_transform (GstBaseTransform * base, GstBuffer * inbuf,
if (!self->have_kernel)
lpwsinc_build_kernel (self);
/* Reset the residue if already existing on discont buffers */
if (GST_BUFFER_IS_DISCONT (inbuf)) {
if (channels && self->residue)
memset (self->residue, 0, channels *
self->kernel_length * sizeof (gdouble));
self->residue_length = 0;
self->next_ts = GST_CLOCK_TIME_NONE;
self->next_off = GST_BUFFER_OFFSET_NONE;
}
/* Calculate the number of samples we can push out now without outputting
* kernel_length/2 zeros in the beginning */
diff = (self->kernel_length / 2) * channels - self->residue_length;
if (diff > 0)
output_samples -= diff;
self->process (self, GST_BUFFER_DATA (inbuf), GST_BUFFER_DATA (outbuf),
input_samples);
if (output_samples <= 0) {
/* Drop buffer and save original timestamp/offset for later use */
if (!GST_CLOCK_TIME_IS_VALID (self->next_ts)
&& GST_BUFFER_TIMESTAMP_IS_VALID (outbuf))
self->next_ts = GST_BUFFER_TIMESTAMP (outbuf);
if (self->next_off == GST_BUFFER_OFFSET_NONE
&& GST_BUFFER_OFFSET_IS_VALID (outbuf))
self->next_off = GST_BUFFER_OFFSET (outbuf);
return GST_BASE_TRANSFORM_FLOW_DROPPED;
} else if (output_samples < input_samples) {
/* First (probably partial) buffer after starting from
* a clean residue. Use stored timestamp/offset here */
if (GST_CLOCK_TIME_IS_VALID (self->next_ts))
GST_BUFFER_TIMESTAMP (outbuf) = self->next_ts;
if (self->next_off != GST_BUFFER_OFFSET_NONE) {
GST_BUFFER_OFFSET (outbuf) = self->next_off;
if (GST_BUFFER_OFFSET_END_IS_VALID (outbuf))
GST_BUFFER_OFFSET_END (outbuf) =
self->next_off + output_samples / channels;
} else {
/* We dropped no buffer, offset is valid, offset_end must be adjusted by diff */
if (GST_BUFFER_OFFSET_END_IS_VALID (outbuf))
GST_BUFFER_OFFSET_END (outbuf) -= diff / channels;
}
if (GST_BUFFER_DURATION_IS_VALID (outbuf))
GST_BUFFER_DURATION (outbuf) -=
gst_util_uint64_scale (diff, GST_SECOND, channels * rate);
GST_BUFFER_DATA (outbuf) +=
diff * (GST_AUDIO_FILTER (self)->format.width / 8);
GST_BUFFER_SIZE (outbuf) -=
diff * (GST_AUDIO_FILTER (self)->format.width / 8);
} else {
GstClockTime ts_latency =
gst_util_uint64_scale (self->latency, GST_SECOND, rate);
/* Normal buffer, adjust timestamp/offset/etc by latency */
if (GST_BUFFER_TIMESTAMP (outbuf) < ts_latency) {
GST_WARNING_OBJECT (self, "GST_BUFFER_TIMESTAMP (outbuf) < latency");
GST_BUFFER_TIMESTAMP (outbuf) = 0;
} else {
GST_BUFFER_TIMESTAMP (outbuf) -= ts_latency;
}
if (GST_BUFFER_OFFSET_IS_VALID (outbuf)) {
if (GST_BUFFER_OFFSET (outbuf) > self->latency) {
GST_BUFFER_OFFSET (outbuf) -= self->latency;
} else {
GST_WARNING_OBJECT (self, "GST_BUFFER_OFFSET (outbuf) < latency");
GST_BUFFER_OFFSET (outbuf) = 0;
}
}
if (GST_BUFFER_OFFSET_END_IS_VALID (outbuf)) {
if (GST_BUFFER_OFFSET_END (outbuf) > self->latency) {
GST_BUFFER_OFFSET_END (outbuf) -= self->latency;
} else {
GST_WARNING_OBJECT (self, "GST_BUFFER_OFFSET_END (outbuf) < latency");
GST_BUFFER_OFFSET_END (outbuf) = 0;
}
}
}
GST_DEBUG_OBJECT (self, "Pushing buffer of size %d with timestamp: %"
GST_TIME_FORMAT ", duration: %" GST_TIME_FORMAT ", offset: %lld,"
" offset_end: %lld, nsamples: %d", GST_BUFFER_SIZE (outbuf),
GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (outbuf)),
GST_TIME_ARGS (GST_BUFFER_DURATION (outbuf)), GST_BUFFER_OFFSET (outbuf),
GST_BUFFER_OFFSET_END (outbuf), output_samples / channels);
self->next_ts = GST_BUFFER_TIMESTAMP (outbuf) + GST_BUFFER_DURATION (outbuf);
self->next_off = GST_BUFFER_OFFSET_END (outbuf);
return GST_FLOW_OK;
}
@ -488,9 +680,93 @@ lpwsinc_start (GstBaseTransform * base)
memset (self->residue, 0, channels *
self->kernel_length * sizeof (gdouble));
self->residue_length = 0;
self->next_ts = GST_CLOCK_TIME_NONE;
self->next_off = GST_BUFFER_OFFSET_NONE;
return TRUE;
}
static gboolean
lpwsinc_query (GstPad * pad, GstQuery * query)
{
GstLPWSinc *self = GST_LPWSINC (gst_pad_get_parent (pad));
gboolean res = TRUE;
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_LATENCY:
{
GstClockTime min, max;
gboolean live;
guint64 latency;
GstPad *peer;
gint rate = GST_AUDIO_FILTER (self)->format.rate;
if ((peer = gst_pad_get_peer (GST_BASE_TRANSFORM (self)->sinkpad))) {
if ((res = gst_pad_query (peer, query))) {
gst_query_parse_latency (query, &live, &min, &max);
GST_DEBUG_OBJECT (self, "Peer latency: min %"
GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
GST_TIME_ARGS (min), GST_TIME_ARGS (max));
/* add our own latency */
latency =
(rate != 0) ? gst_util_uint64_scale (self->latency, GST_SECOND,
rate) : 0;
GST_DEBUG_OBJECT (self, "Our latency: %"
GST_TIME_FORMAT, GST_TIME_ARGS (latency));
min += latency;
if (max != GST_CLOCK_TIME_NONE)
max += latency;
GST_DEBUG_OBJECT (self, "Calculated total latency : min %"
GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
GST_TIME_ARGS (min), GST_TIME_ARGS (max));
gst_query_set_latency (query, live, min, max);
}
gst_object_unref (peer);
}
break;
}
default:
res = gst_pad_query_default (pad, query);
break;
}
gst_object_unref (self);
return res;
}
static const GstQueryType *
lpwsinc_query_type (GstPad * pad)
{
static const GstQueryType types[] = {
GST_QUERY_LATENCY,
0
};
return types;
}
static gboolean
lpwsinc_event (GstBaseTransform * base, GstEvent * event)
{
GstLPWSinc *self = GST_LPWSINC (base);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_EOS:
lpwsinc_push_residue (self);
break;
default:
break;
}
return GST_BASE_TRANSFORM_CLASS (parent_class)->event (base, event);
}
static void
lpwsinc_set_property (GObject * object, guint prop_id, const GValue * value,
GParamSpec * pspec)
@ -507,8 +783,17 @@ lpwsinc_set_property (GObject * object, guint prop_id, const GValue * value,
val = g_value_get_int (value);
if (val % 2 == 0)
val++;
self->kernel_length = val;
lpwsinc_build_kernel (self);
if (val != self->kernel_length) {
if (self->residue) {
lpwsinc_push_residue (self);
g_free (self->residue);
self->residue = NULL;
}
self->kernel_length = val;
self->latency = val / 2;
lpwsinc_build_kernel (self);
}
GST_BASE_TRANSFORM_UNLOCK (self);
break;
}

4
gst/audiofx/audiowsinclimit.h
View file

@ -71,6 +71,10 @@ struct _GstLPWSinc {
gdouble *residue; /* buffer for left-over samples from previous buffer */
gdouble *kernel; /* filter kernel */
gboolean have_kernel;
gint residue_length;
guint64 latency;
GstClockTime next_ts;
guint64 next_off;
};
struct _GstLPWSincClass {

110
tests/check/elements/audiowsinclimit.c
View file

@ -96,6 +96,7 @@ GST_START_TEST (test_lp_0hz)
GstCaps *caps;
gdouble *in, *res, rms;
gint i;
GList *node;
lpwsinc = setup_lpwsinc ();
/* Set to lowpass */
@ -120,22 +121,24 @@ GST_START_TEST (test_lp_0hz)
/* pushing gives away my reference ... */
fail_unless (gst_pad_push (mysrcpad, inbuffer) == GST_FLOW_OK);
fail_unless (gst_pad_push_event (mysrcpad, gst_event_new_eos ()));
/* ... and puts a new buffer on the global list */
fail_unless_equals_int (g_list_length (buffers), 1);
fail_if ((outbuffer = (GstBuffer *) buffers->data) == NULL);
fail_unless (g_list_length (buffers) >= 1);
res = (gdouble *) GST_BUFFER_DATA (outbuffer);
for (i = 21; i < 128; i++) {
fail_unless (res[i] <= 1.01
&& res[i] >= 0.99, "res[%d] = %lf\n", i, res[i]);
for (node = buffers; node; node = node->next) {
gint buffer_length;
fail_if ((outbuffer = (GstBuffer *) node->data) == NULL);
res = (gdouble *) GST_BUFFER_DATA (outbuffer);
buffer_length = GST_BUFFER_SIZE (outbuffer) / sizeof (gdouble);
rms = 0.0;
for (i = 0; i < buffer_length; i++)
rms += res[i] * res[i];
rms = sqrt (rms / buffer_length);
fail_unless (rms >= 0.9);
}
rms = 0.0;
for (i = 0; i < 128; i++)
rms += res[i] * res[i];
rms = sqrt (rms / 128.0);
fail_unless (rms >= 0.9);
/* cleanup */
cleanup_lpwsinc (lpwsinc);
}
@ -152,6 +155,7 @@ GST_START_TEST (test_lp_22050hz)
GstCaps *caps;
gdouble *in, *res, rms;
gint i;
GList *node;
lpwsinc = setup_lpwsinc ();
/* Set to lowpass */
@ -177,22 +181,24 @@ GST_START_TEST (test_lp_22050hz)
/* pushing gives away my reference ... */
fail_unless (gst_pad_push (mysrcpad, inbuffer) == GST_FLOW_OK);
fail_unless (gst_pad_push_event (mysrcpad, gst_event_new_eos ()));
/* ... and puts a new buffer on the global list */
fail_unless_equals_int (g_list_length (buffers), 1);
fail_if ((outbuffer = (GstBuffer *) buffers->data) == NULL);
fail_unless (g_list_length (buffers) >= 1);
res = (gdouble *) GST_BUFFER_DATA (outbuffer);
for (i = 21; i < 128; i++) {
fail_unless (res[i] <= 0.01
&& res[i] >= -0.01, "res[%d] = %lf\n", i, res[i]);
for (node = buffers; node; node = node->next) {
gint buffer_length;
fail_if ((outbuffer = (GstBuffer *) node->data) == NULL);
res = (gdouble *) GST_BUFFER_DATA (outbuffer);
buffer_length = GST_BUFFER_SIZE (outbuffer) / sizeof (gdouble);
rms = 0.0;
for (i = 0; i < buffer_length; i++)
rms += res[i] * res[i];
rms = sqrt (rms / buffer_length);
fail_unless (rms <= 0.1);
}
rms = 0.0;
for (i = 0; i < 128; i++)
rms += res[i] * res[i];
rms = sqrt (rms / 128.0);
fail_unless (rms <= 0.05);
/* cleanup */
cleanup_lpwsinc (lpwsinc);
}
@ -209,6 +215,7 @@ GST_START_TEST (test_hp_0hz)
GstCaps *caps;
gdouble *in, *res, rms;
gint i;
GList *node;
lpwsinc = setup_lpwsinc ();
/* Set to highpass */
@ -232,22 +239,24 @@ GST_START_TEST (test_hp_0hz)
/* pushing gives away my reference ... */
fail_unless (gst_pad_push (mysrcpad, inbuffer) == GST_FLOW_OK);
fail_unless (gst_pad_push_event (mysrcpad, gst_event_new_eos ()));
/* ... and puts a new buffer on the global list */
fail_unless_equals_int (g_list_length (buffers), 1);
fail_if ((outbuffer = (GstBuffer *) buffers->data) == NULL);
fail_unless (g_list_length (buffers) >= 1);
res = (gdouble *) GST_BUFFER_DATA (outbuffer);
for (i = 21; i < 128; i++) {
fail_unless (res[i] <= 0.01
&& res[i] >= -0.01, "res[%d] = %lf\n", i, res[i]);
for (node = buffers; node; node = node->next) {
gint buffer_length;
fail_if ((outbuffer = (GstBuffer *) node->data) == NULL);
res = (gdouble *) GST_BUFFER_DATA (outbuffer);
buffer_length = GST_BUFFER_SIZE (outbuffer) / sizeof (gdouble);
rms = 0.0;
for (i = 0; i < buffer_length; i++)
rms += res[i] * res[i];
rms = sqrt (rms / buffer_length);
fail_unless (rms <= 0.1);
}
rms = 0.0;
for (i = 0; i < 128; i++)
rms += res[i] * res[i];
rms = sqrt (rms / 128.0);
fail_unless (rms <= 0.05);
/* cleanup */
cleanup_lpwsinc (lpwsinc);
}
@ -264,6 +273,7 @@ GST_START_TEST (test_hp_22050hz)
GstCaps *caps;
gdouble *in, *res, rms;
gint i;
GList *node;
lpwsinc = setup_lpwsinc ();
/* Set to highpass */
@ -289,21 +299,24 @@ GST_START_TEST (test_hp_22050hz)
/* pushing gives away my reference ... */
fail_unless (gst_pad_push (mysrcpad, inbuffer) == GST_FLOW_OK);
fail_unless (gst_pad_push_event (mysrcpad, gst_event_new_eos ()));
/* ... and puts a new buffer on the global list */
fail_unless_equals_int (g_list_length (buffers), 1);
fail_unless (g_list_length (buffers) >= 1);
fail_if ((outbuffer = (GstBuffer *) buffers->data) == NULL);
res = (gdouble *) GST_BUFFER_DATA (outbuffer);
for (i = 21; i < 128; i++) {
fail_unless (abs (res[i]) <= 1.01
&& abs (res[i]) >= 0.99, "res[%d] = %lf\n", i, res[i]);
}
for (node = buffers; node; node = node->next) {
gint buffer_length;
rms = 0.0;
for (i = 0; i < 128; i++)
rms += res[i] * res[i];
rms = sqrt (rms / 128.0);
fail_unless (rms >= 0.9);
fail_if ((outbuffer = (GstBuffer *) node->data) == NULL);
res = (gdouble *) GST_BUFFER_DATA (outbuffer);
buffer_length = GST_BUFFER_SIZE (outbuffer) / sizeof (gdouble);
rms = 0.0;
for (i = 0; i < buffer_length; i++)
rms += res[i] * res[i];
rms = sqrt (rms / buffer_length);
fail_unless (rms >= 0.9);
}
/* cleanup */
cleanup_lpwsinc (lpwsinc);
@ -344,8 +357,9 @@ GST_START_TEST (test_small_buffer)
/* pushing gives away my reference ... */
fail_unless (gst_pad_push (mysrcpad, inbuffer) == GST_FLOW_OK);
fail_unless (gst_pad_push_event (mysrcpad, gst_event_new_eos ()));
/* ... and puts a new buffer on the global list */
fail_unless_equals_int (g_list_length (buffers), 1);
fail_unless (g_list_length (buffers) >= 1);
fail_if ((outbuffer = (GstBuffer *) buffers->data) == NULL);
/* cleanup */