2 * Copyright (C) 2008 Ole André Vadla Ravnås <ole.andre.ravnas@tandberg.com>
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
21 * SECTION:element-wasapisrc
23 * Provides audio capture from the Windows Audio Session API available with
27 * <title>Example pipelines</title>
29 * gst-launch-1.0 -v wasapisrc ! fakesink
30 * ]| Capture from the default audio device and render to fakesink.
37 #include "gstwasapisrc.h"
38 #include <gst/audio/gstaudioclock.h>
40 GST_DEBUG_CATEGORY_STATIC (gst_wasapi_src_debug);
41 #define GST_CAT_DEFAULT gst_wasapi_src_debug
43 static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
46 GST_STATIC_CAPS ("audio/x-raw, "
47 "format = (string) S16LE, "
48 "layout = (string) interleaved, "
49 "rate = (int) 8000, " "channels = (int) 1"));
51 static void gst_wasapi_src_dispose (GObject * object);
52 static void gst_wasapi_src_finalize (GObject * object);
54 static GstClock *gst_wasapi_src_provide_clock (GstElement * element);
56 static gboolean gst_wasapi_src_start (GstBaseSrc * src);
57 static gboolean gst_wasapi_src_stop (GstBaseSrc * src);
58 static gboolean gst_wasapi_src_query (GstBaseSrc * src, GstQuery * query);
60 static GstFlowReturn gst_wasapi_src_create (GstPushSrc * src, GstBuffer ** buf);
62 static GstClockTime gst_wasapi_src_get_time (GstClock * clock,
65 G_DEFINE_TYPE (GstWasapiSrc, gst_wasapi_src, GST_TYPE_PUSH_SRC);
68 gst_wasapi_src_class_init (GstWasapiSrcClass * klass)
70 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
71 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
72 GstBaseSrcClass *gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
73 GstPushSrcClass *gstpushsrc_class = GST_PUSH_SRC_CLASS (klass);
75 gobject_class->dispose = gst_wasapi_src_dispose;
76 gobject_class->finalize = gst_wasapi_src_finalize;
78 gstelement_class->provide_clock = gst_wasapi_src_provide_clock;
80 gst_element_class_add_pad_template (gstelement_class,
81 gst_static_pad_template_get (&src_template));
82 gst_element_class_set_static_metadata (gstelement_class, "WasapiSrc",
84 "Stream audio from an audio capture device through WASAPI",
85 "Ole André Vadla Ravnås <ole.andre.ravnas@tandberg.com>");
87 gstbasesrc_class->start = gst_wasapi_src_start;
88 gstbasesrc_class->stop = gst_wasapi_src_stop;
89 gstbasesrc_class->query = gst_wasapi_src_query;
91 gstpushsrc_class->create = gst_wasapi_src_create;
93 GST_DEBUG_CATEGORY_INIT (gst_wasapi_src_debug, "wasapisrc",
94 0, "Windows audio session API source");
98 gst_wasapi_src_init (GstWasapiSrc * self)
100 GstBaseSrc *basesrc = GST_BASE_SRC (self);
102 gst_base_src_set_format (basesrc, GST_FORMAT_TIME);
103 gst_base_src_set_live (basesrc, TRUE);
106 self->buffer_time = 20 * GST_MSECOND;
107 self->period_time = 20 * GST_MSECOND;
108 self->latency = GST_CLOCK_TIME_NONE;
109 self->samples_per_buffer = self->rate / (GST_SECOND / self->period_time);
111 self->start_time = GST_CLOCK_TIME_NONE;
112 self->next_time = GST_CLOCK_TIME_NONE;
114 self->clock = gst_audio_clock_new ("GstWasapiSrcClock",
115 gst_wasapi_src_get_time, gst_object_ref (self),
116 (GDestroyNotify) gst_object_unref);
122 gst_wasapi_src_dispose (GObject * object)
124 GstWasapiSrc *self = GST_WASAPI_SRC (object);
126 if (self->clock != NULL) {
127 gst_object_unref (self->clock);
131 G_OBJECT_CLASS (gst_wasapi_src_parent_class)->dispose (object);
135 gst_wasapi_src_finalize (GObject * object)
139 G_OBJECT_CLASS (gst_wasapi_src_parent_class)->finalize (object);
143 gst_wasapi_src_provide_clock (GstElement * element)
145 GstWasapiSrc *self = GST_WASAPI_SRC (element);
148 GST_OBJECT_LOCK (self);
150 if (self->client_clock == NULL)
153 clock = GST_CLOCK (gst_object_ref (self->clock));
155 GST_OBJECT_UNLOCK (self);
161 GST_OBJECT_UNLOCK (self);
162 GST_DEBUG_OBJECT (self, "IAudioClock not acquired");
168 gst_wasapi_src_start (GstBaseSrc * src)
170 GstWasapiSrc *self = GST_WASAPI_SRC (src);
171 gboolean res = FALSE;
172 IAudioClient *client = NULL;
173 IAudioClock *client_clock = NULL;
174 guint64 client_clock_freq = 0;
175 IAudioCaptureClient *capture_client = NULL;
178 if (!gst_wasapi_util_get_default_device_client (GST_ELEMENT (self),
179 TRUE, self->rate, self->buffer_time, self->period_time, 0, &client,
183 hr = IAudioClient_GetService (client, &IID_IAudioClock,
184 (void **) &client_clock);
186 GST_ERROR_OBJECT (self, "IAudioClient::GetService (IID_IAudioClock) "
191 hr = IAudioClock_GetFrequency (client_clock, &client_clock_freq);
193 GST_ERROR_OBJECT (self, "IAudioClock::GetFrequency () failed");
197 hr = IAudioClient_GetService (client, &IID_IAudioCaptureClient,
198 (void **) &capture_client);
200 GST_ERROR_OBJECT (self, "IAudioClient::GetService "
201 "(IID_IAudioCaptureClient) failed");
205 hr = IAudioClient_Start (client);
207 GST_ERROR_OBJECT (self, "IAudioClient::Start failed");
211 self->client = client;
212 self->client_clock = client_clock;
213 self->client_clock_freq = client_clock_freq;
214 self->capture_client = capture_client;
220 if (capture_client != NULL)
221 IUnknown_Release (capture_client);
223 if (client_clock != NULL)
224 IUnknown_Release (client_clock);
227 IUnknown_Release (client);
234 gst_wasapi_src_stop (GstBaseSrc * src)
236 GstWasapiSrc *self = GST_WASAPI_SRC (src);
238 if (self->client != NULL) {
239 IAudioClient_Stop (self->client);
242 if (self->capture_client != NULL) {
243 IUnknown_Release (self->capture_client);
244 self->capture_client = NULL;
247 if (self->client_clock != NULL) {
248 IUnknown_Release (self->client_clock);
249 self->client_clock = NULL;
252 if (self->client != NULL) {
253 IUnknown_Release (self->client);
261 gst_wasapi_src_query (GstBaseSrc * src, GstQuery * query)
263 GstWasapiSrc *self = GST_WASAPI_SRC (src);
264 gboolean ret = FALSE;
266 GST_DEBUG_OBJECT (self, "query for %s",
267 gst_query_type_get_name (GST_QUERY_TYPE (query)));
269 switch (GST_QUERY_TYPE (query)) {
270 case GST_QUERY_LATENCY:{
271 GstClockTime min_latency, max_latency;
273 min_latency = self->latency + self->period_time;
274 max_latency = min_latency;
276 GST_DEBUG_OBJECT (self, "reporting latency of min %" GST_TIME_FORMAT
277 " max %" GST_TIME_FORMAT,
278 GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));
280 gst_query_set_latency (query, TRUE, min_latency, max_latency);
287 GST_BASE_SRC_CLASS (gst_wasapi_src_parent_class)->query (src, query);
295 gst_wasapi_src_create (GstPushSrc * src, GstBuffer ** buf)
297 GstWasapiSrc *self = GST_WASAPI_SRC (src);
298 GstFlowReturn ret = GST_FLOW_OK;
300 GstClockTime timestamp, duration = self->period_time;
302 gint16 *samples = NULL;
303 guint32 nsamples_read = 0, nsamples;
310 GST_OBJECT_LOCK (self);
311 clock = GST_ELEMENT_CLOCK (self);
313 gst_object_ref (clock);
314 GST_OBJECT_UNLOCK (self);
316 if (clock != NULL && GST_CLOCK_TIME_IS_VALID (self->next_time)) {
319 id = gst_clock_new_single_shot_id (clock, self->next_time);
320 gst_clock_id_wait (id, NULL);
321 gst_clock_id_unref (id);
325 hr = IAudioCaptureClient_GetBuffer (self->capture_client,
326 (BYTE **) & samples, &nsamples_read, &flags, &devpos, NULL);
328 while (hr == AUDCLNT_S_BUFFER_EMPTY);
331 GST_ERROR_OBJECT (self, "IAudioCaptureClient::GetBuffer () failed: %s",
332 gst_wasapi_util_hresult_to_string (hr));
333 ret = GST_FLOW_ERROR;
338 GST_WARNING_OBJECT (self, "devpos %" G_GUINT64_FORMAT ": flags=0x%08x",
339 devpos, (guint) flags);
342 /* FIXME: Why do we get 1024 sometimes and not a multiple of
343 * samples_per_buffer? Shouldn't WASAPI provide a DISCONT
344 * flag if we read too slow?
346 nsamples = nsamples_read;
347 g_assert (nsamples >= self->samples_per_buffer);
348 if (nsamples > self->samples_per_buffer) {
349 GST_WARNING_OBJECT (self,
350 "devpos %" G_GUINT64_FORMAT ": got %d samples, expected %d, clipping!",
351 devpos, nsamples, self->samples_per_buffer);
353 nsamples = self->samples_per_buffer;
356 if (clock == NULL || clock == self->clock) {
358 gst_util_uint64_scale (devpos, GST_SECOND, self->client_clock_freq);
360 GstClockTime base_time;
362 timestamp = gst_clock_get_time (clock);
364 base_time = GST_ELEMENT_CAST (self)->base_time;
365 if (timestamp > base_time)
366 timestamp -= base_time;
370 if (timestamp > duration)
371 timestamp -= duration;
376 *buf = gst_buffer_new_and_alloc (nsamples * sizeof (gint16));
378 GST_BUFFER_OFFSET_END (*buf) = devpos + self->samples_per_buffer;
379 GST_BUFFER_TIMESTAMP (*buf) = timestamp;
380 GST_BUFFER_DURATION (*buf) = duration;
382 gst_buffer_map (*buf, &minfo, GST_MAP_WRITE);
383 dst = (gint16 *) minfo.data;
384 for (i = 0; i < nsamples; i++) {
390 gst_buffer_unmap (*buf, &minfo);
392 hr = IAudioCaptureClient_ReleaseBuffer (self->capture_client, nsamples_read);
394 GST_ERROR_OBJECT (self, "IAudioCaptureClient::ReleaseBuffer () failed: %s",
395 gst_wasapi_util_hresult_to_string (hr));
396 ret = GST_FLOW_ERROR;
402 gst_object_unref (clock);
408 gst_wasapi_src_get_time (GstClock * clock, gpointer user_data)
410 GstWasapiSrc *self = GST_WASAPI_SRC (user_data);
415 if (G_UNLIKELY (self->client_clock == NULL))
416 return GST_CLOCK_TIME_NONE;
418 hr = IAudioClock_GetPosition (self->client_clock, &devpos, NULL);
419 if (G_UNLIKELY (hr != S_OK))
420 return GST_CLOCK_TIME_NONE;
422 result = gst_util_uint64_scale_int (devpos, GST_SECOND,
423 self->client_clock_freq);
426 GST_DEBUG_OBJECT (self, "devpos = %" G_GUINT64_FORMAT
427 " frequency = %" G_GUINT64_FORMAT
428 " result = %" G_GUINT64_FORMAT " ms",
429 devpos, self->client_clock_freq, GST_TIME_AS_MSECONDS (result));