--- /dev/null
+/* GStreamer
+ * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
+ * 2005 Wim Taymans <wim@fluendo.com>
+ *
+ * gstbaseaudiosrc.c:
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * SECTION:gstbaseaudiosrc
+ * @short_description: Base class for audio sources
+ * @see_also: #GstAudioSrc, #GstRingBuffer.
+ *
+ * This is the base class for audio sources. Subclasses need to implement the
+ * ::create_ringbuffer vmethod. This base class will then take care of
+ * reading samples from the ringbuffer, synchronisation and flushing.
+ *
+ * Last reviewed on 2006-09-27 (0.10.12)
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <string.h>
+
+#include "gstbaseaudiosrc.h"
+
+#include "gst/gst-i18n-plugin.h"
+
+GST_DEBUG_CATEGORY_STATIC (gst_base_audio_src_debug);
+#define GST_CAT_DEFAULT gst_base_audio_src_debug
+
+GType
+gst_base_audio_src_slave_method_get_type (void)
+{
+ static volatile gsize slave_method_type = 0;
+ /* FIXME 0.11: nick should be "retimestamp" not "re-timestamp" */
+ static const GEnumValue slave_method[] = {
+ {GST_BASE_AUDIO_SRC_SLAVE_RESAMPLE,
+ "GST_BASE_AUDIO_SRC_SLAVE_RESAMPLE", "resample"},
+ {GST_BASE_AUDIO_SRC_SLAVE_RETIMESTAMP,
+ "GST_BASE_AUDIO_SRC_SLAVE_RETIMESTAMP", "re-timestamp"},
+ {GST_BASE_AUDIO_SRC_SLAVE_SKEW, "GST_BASE_AUDIO_SRC_SLAVE_SKEW", "skew"},
+ {GST_BASE_AUDIO_SRC_SLAVE_NONE, "GST_BASE_AUDIO_SRC_SLAVE_NONE", "none"},
+ {0, NULL, NULL},
+ };
+
+ if (g_once_init_enter (&slave_method_type)) {
+ GType tmp =
+ g_enum_register_static ("GstBaseAudioSrcSlaveMethod", slave_method);
+ g_once_init_leave (&slave_method_type, tmp);
+ }
+ return (GType) slave_method_type;
+}
+
+#define GST_BASE_AUDIO_SRC_GET_PRIVATE(obj) \
+ (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BASE_AUDIO_SRC, GstBaseAudioSrcPrivate))
+
+struct _GstBaseAudioSrcPrivate
+{
+ gboolean provide_clock;
+
+ /* the clock slaving algorithm in use */
+ GstBaseAudioSrcSlaveMethod slave_method;
+};
+
+/* BaseAudioSrc signals and args */
+enum
+{
+ /* FILL ME */
+ LAST_SIGNAL
+};
+
+#define DEFAULT_BUFFER_TIME ((200 * GST_MSECOND) / GST_USECOND)
+#define DEFAULT_LATENCY_TIME ((10 * GST_MSECOND) / GST_USECOND)
+#define DEFAULT_ACTUAL_BUFFER_TIME -1
+#define DEFAULT_ACTUAL_LATENCY_TIME -1
+#define DEFAULT_PROVIDE_CLOCK TRUE
+#define DEFAULT_SLAVE_METHOD GST_BASE_AUDIO_SRC_SLAVE_SKEW
+
+enum
+{
+ PROP_0,
+ PROP_BUFFER_TIME,
+ PROP_LATENCY_TIME,
+ PROP_ACTUAL_BUFFER_TIME,
+ PROP_ACTUAL_LATENCY_TIME,
+ PROP_PROVIDE_CLOCK,
+ PROP_SLAVE_METHOD,
+ PROP_LAST
+};
+
+static void
+_do_init (GType type)
+{
+ GST_DEBUG_CATEGORY_INIT (gst_base_audio_src_debug, "baseaudiosrc", 0,
+ "baseaudiosrc element");
+
+#ifdef ENABLE_NLS
+ GST_DEBUG ("binding text domain %s to locale dir %s", GETTEXT_PACKAGE,
+ LOCALEDIR);
+ bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
+ bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
+#endif /* ENABLE_NLS */
+}
+
+GST_BOILERPLATE_FULL (GstBaseAudioSrc, gst_base_audio_src, GstPushSrc,
+ GST_TYPE_PUSH_SRC, _do_init);
+
+static void gst_base_audio_src_set_property (GObject * object, guint prop_id,
+ const GValue * value, GParamSpec * pspec);
+static void gst_base_audio_src_get_property (GObject * object, guint prop_id,
+ GValue * value, GParamSpec * pspec);
+static void gst_base_audio_src_dispose (GObject * object);
+
+static GstStateChangeReturn gst_base_audio_src_change_state (GstElement *
+ element, GstStateChange transition);
+
+static GstClock *gst_base_audio_src_provide_clock (GstElement * elem);
+static GstClockTime gst_base_audio_src_get_time (GstClock * clock,
+ GstBaseAudioSrc * src);
+
+static GstFlowReturn gst_base_audio_src_create (GstBaseSrc * bsrc,
+ guint64 offset, guint length, GstBuffer ** buf);
+static gboolean gst_base_audio_src_check_get_range (GstBaseSrc * bsrc);
+
+static gboolean gst_base_audio_src_event (GstBaseSrc * bsrc, GstEvent * event);
+static void gst_base_audio_src_get_times (GstBaseSrc * bsrc,
+ GstBuffer * buffer, GstClockTime * start, GstClockTime * end);
+static gboolean gst_base_audio_src_setcaps (GstBaseSrc * bsrc, GstCaps * caps);
+static gboolean gst_base_audio_src_query (GstBaseSrc * bsrc, GstQuery * query);
+static void gst_base_audio_src_fixate (GstBaseSrc * bsrc, GstCaps * caps);
+
+/* static guint gst_base_audio_src_signals[LAST_SIGNAL] = { 0 }; */
+
+static void
+gst_base_audio_src_base_init (gpointer g_class)
+{
+}
+
+static void
+gst_base_audio_src_class_init (GstBaseAudioSrcClass * klass)
+{
+ GObjectClass *gobject_class;
+ GstElementClass *gstelement_class;
+ GstBaseSrcClass *gstbasesrc_class;
+
+ gobject_class = (GObjectClass *) klass;
+ gstelement_class = (GstElementClass *) klass;
+ gstbasesrc_class = (GstBaseSrcClass *) klass;
+
+ g_type_class_add_private (klass, sizeof (GstBaseAudioSrcPrivate));
+
+ gobject_class->set_property = gst_base_audio_src_set_property;
+ gobject_class->get_property = gst_base_audio_src_get_property;
+ gobject_class->dispose = gst_base_audio_src_dispose;
+
+ g_object_class_install_property (gobject_class, PROP_BUFFER_TIME,
+ g_param_spec_int64 ("buffer-time", "Buffer Time",
+ "Size of audio buffer in microseconds", 1,
+ G_MAXINT64, DEFAULT_BUFFER_TIME,
+ G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ g_object_class_install_property (gobject_class, PROP_LATENCY_TIME,
+ g_param_spec_int64 ("latency-time", "Latency Time",
+ "Audio latency in microseconds", 1,
+ G_MAXINT64, DEFAULT_LATENCY_TIME,
+ G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ /**
+ * GstBaseAudioSrc:actual-buffer-time:
+ *
+ * Actual configured size of audio buffer in microseconds.
+ *
+ * Since: 0.10.20
+ **/
+ g_object_class_install_property (gobject_class, PROP_ACTUAL_BUFFER_TIME,
+ g_param_spec_int64 ("actual-buffer-time", "Actual Buffer Time",
+ "Actual configured size of audio buffer in microseconds",
+ DEFAULT_ACTUAL_BUFFER_TIME, G_MAXINT64, DEFAULT_ACTUAL_BUFFER_TIME,
+ G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
+
+ /**
+ * GstBaseAudioSrc:actual-latency-time:
+ *
+ * Actual configured audio latency in microseconds.
+ *
+ * Since: 0.10.20
+ **/
+ g_object_class_install_property (gobject_class, PROP_ACTUAL_LATENCY_TIME,
+ g_param_spec_int64 ("actual-latency-time", "Actual Latency Time",
+ "Actual configured audio latency in microseconds",
+ DEFAULT_ACTUAL_LATENCY_TIME, G_MAXINT64, DEFAULT_ACTUAL_LATENCY_TIME,
+ G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
+
+ g_object_class_install_property (gobject_class, PROP_PROVIDE_CLOCK,
+ g_param_spec_boolean ("provide-clock", "Provide Clock",
+ "Provide a clock to be used as the global pipeline clock",
+ DEFAULT_PROVIDE_CLOCK, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ g_object_class_install_property (gobject_class, PROP_SLAVE_METHOD,
+ g_param_spec_enum ("slave-method", "Slave Method",
+ "Algorithm to use to match the rate of the masterclock",
+ GST_TYPE_BASE_AUDIO_SRC_SLAVE_METHOD, DEFAULT_SLAVE_METHOD,
+ G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ gstelement_class->change_state =
+ GST_DEBUG_FUNCPTR (gst_base_audio_src_change_state);
+ gstelement_class->provide_clock =
+ GST_DEBUG_FUNCPTR (gst_base_audio_src_provide_clock);
+
+ gstbasesrc_class->set_caps = GST_DEBUG_FUNCPTR (gst_base_audio_src_setcaps);
+ gstbasesrc_class->event = GST_DEBUG_FUNCPTR (gst_base_audio_src_event);
+ gstbasesrc_class->query = GST_DEBUG_FUNCPTR (gst_base_audio_src_query);
+ gstbasesrc_class->get_times =
+ GST_DEBUG_FUNCPTR (gst_base_audio_src_get_times);
+ gstbasesrc_class->create = GST_DEBUG_FUNCPTR (gst_base_audio_src_create);
+ gstbasesrc_class->check_get_range =
+ GST_DEBUG_FUNCPTR (gst_base_audio_src_check_get_range);
+ gstbasesrc_class->fixate = GST_DEBUG_FUNCPTR (gst_base_audio_src_fixate);
+
+ /* ref class from a thread-safe context to work around missing bit of
+ * thread-safety in GObject */
+ g_type_class_ref (GST_TYPE_AUDIO_CLOCK);
+ g_type_class_ref (GST_TYPE_RING_BUFFER);
+}
+
+static void
+gst_base_audio_src_init (GstBaseAudioSrc * baseaudiosrc,
+ GstBaseAudioSrcClass * g_class)
+{
+ baseaudiosrc->priv = GST_BASE_AUDIO_SRC_GET_PRIVATE (baseaudiosrc);
+
+ baseaudiosrc->buffer_time = DEFAULT_BUFFER_TIME;
+ baseaudiosrc->latency_time = DEFAULT_LATENCY_TIME;
+ baseaudiosrc->priv->provide_clock = DEFAULT_PROVIDE_CLOCK;
+ baseaudiosrc->priv->slave_method = DEFAULT_SLAVE_METHOD;
+ /* reset blocksize we use latency time to calculate a more useful
+ * value based on negotiated format. */
+ GST_BASE_SRC (baseaudiosrc)->blocksize = 0;
+
+ baseaudiosrc->clock = gst_audio_clock_new ("GstAudioSrcClock",
+ (GstAudioClockGetTimeFunc) gst_base_audio_src_get_time, baseaudiosrc);
+
+ /* we are always a live source */
+ gst_base_src_set_live (GST_BASE_SRC (baseaudiosrc), TRUE);
+ /* we operate in time */
+ gst_base_src_set_format (GST_BASE_SRC (baseaudiosrc), GST_FORMAT_TIME);
+}
+
+static void
+gst_base_audio_src_dispose (GObject * object)
+{
+ GstBaseAudioSrc *src;
+
+ src = GST_BASE_AUDIO_SRC (object);
+
+ GST_OBJECT_LOCK (src);
+ if (src->clock) {
+ gst_audio_clock_invalidate (src->clock);
+ gst_object_unref (src->clock);
+ src->clock = NULL;
+ }
+
+ if (src->ringbuffer) {
+ gst_object_unparent (GST_OBJECT_CAST (src->ringbuffer));
+ src->ringbuffer = NULL;
+ }
+ GST_OBJECT_UNLOCK (src);
+
+ G_OBJECT_CLASS (parent_class)->dispose (object);
+}
+
+static GstClock *
+gst_base_audio_src_provide_clock (GstElement * elem)
+{
+ GstBaseAudioSrc *src;
+ GstClock *clock;
+
+ src = GST_BASE_AUDIO_SRC (elem);
+
+ /* we have no ringbuffer (must be NULL state) */
+ if (src->ringbuffer == NULL)
+ goto wrong_state;
+
+ if (!gst_ring_buffer_is_acquired (src->ringbuffer))
+ goto wrong_state;
+
+ GST_OBJECT_LOCK (src);
+ if (!src->priv->provide_clock)
+ goto clock_disabled;
+
+ clock = GST_CLOCK_CAST (gst_object_ref (src->clock));
+ GST_OBJECT_UNLOCK (src);
+
+ return clock;
+
+ /* ERRORS */
+wrong_state:
+ {
+ GST_DEBUG_OBJECT (src, "ringbuffer not acquired");
+ return NULL;
+ }
+clock_disabled:
+ {
+ GST_DEBUG_OBJECT (src, "clock provide disabled");
+ GST_OBJECT_UNLOCK (src);
+ return NULL;
+ }
+}
+
+static GstClockTime
+gst_base_audio_src_get_time (GstClock * clock, GstBaseAudioSrc * src)
+{
+ guint64 raw, samples;
+ guint delay;
+ GstClockTime result;
+
+ if (G_UNLIKELY (src->ringbuffer == NULL || src->ringbuffer->spec.rate == 0))
+ return GST_CLOCK_TIME_NONE;
+
+ raw = samples = gst_ring_buffer_samples_done (src->ringbuffer);
+
+ /* the number of samples not yet processed, this is still queued in the
+ * device (not yet read for capture). */
+ delay = gst_ring_buffer_delay (src->ringbuffer);
+
+ samples += delay;
+
+ result = gst_util_uint64_scale_int (samples, GST_SECOND,
+ src->ringbuffer->spec.rate);
+
+ GST_DEBUG_OBJECT (src,
+ "processed samples: raw %" G_GUINT64_FORMAT ", delay %u, real %"
+ G_GUINT64_FORMAT ", time %" GST_TIME_FORMAT, raw, delay, samples,
+ GST_TIME_ARGS (result));
+
+ return result;
+}
+
+static gboolean
+gst_base_audio_src_check_get_range (GstBaseSrc * bsrc)
+{
+ /* we allow limited pull base operation of which the details
+ * will eventually exposed in an as of yet non-existing query.
+ * Basically pulling can be done on any number of bytes as long
+ * as the offset is -1 or sequentially increasing. */
+ return TRUE;
+}
+
+/**
+ * gst_base_audio_src_set_provide_clock:
+ * @src: a #GstBaseAudioSrc
+ * @provide: new state
+ *
+ * Controls whether @src will provide a clock or not. If @provide is %TRUE,
+ * gst_element_provide_clock() will return a clock that reflects the datarate
+ * of @src. If @provide is %FALSE, gst_element_provide_clock() will return NULL.
+ *
+ * Since: 0.10.16
+ */
+void
+gst_base_audio_src_set_provide_clock (GstBaseAudioSrc * src, gboolean provide)
+{
+ g_return_if_fail (GST_IS_BASE_AUDIO_SRC (src));
+
+ GST_OBJECT_LOCK (src);
+ src->priv->provide_clock = provide;
+ GST_OBJECT_UNLOCK (src);
+}
+
+/**
+ * gst_base_audio_src_get_provide_clock:
+ * @src: a #GstBaseAudioSrc
+ *
+ * Queries whether @src will provide a clock or not. See also
+ * gst_base_audio_src_set_provide_clock.
+ *
+ * Returns: %TRUE if @src will provide a clock.
+ *
+ * Since: 0.10.16
+ */
+gboolean
+gst_base_audio_src_get_provide_clock (GstBaseAudioSrc * src)
+{
+ gboolean result;
+
+ g_return_val_if_fail (GST_IS_BASE_AUDIO_SRC (src), FALSE);
+
+ GST_OBJECT_LOCK (src);
+ result = src->priv->provide_clock;
+ GST_OBJECT_UNLOCK (src);
+
+ return result;
+}
+
+/**
+ * gst_base_audio_src_set_slave_method:
+ * @src: a #GstBaseAudioSrc
+ * @method: the new slave method
+ *
+ * Controls how clock slaving will be performed in @src.
+ *
+ * Since: 0.10.20
+ */
+void
+gst_base_audio_src_set_slave_method (GstBaseAudioSrc * src,
+ GstBaseAudioSrcSlaveMethod method)
+{
+ g_return_if_fail (GST_IS_BASE_AUDIO_SRC (src));
+
+ GST_OBJECT_LOCK (src);
+ src->priv->slave_method = method;
+ GST_OBJECT_UNLOCK (src);
+}
+
+/**
+ * gst_base_audio_src_get_slave_method:
+ * @src: a #GstBaseAudioSrc
+ *
+ * Get the current slave method used by @src.
+ *
+ * Returns: The current slave method used by @src.
+ *
+ * Since: 0.10.20
+ */
+GstBaseAudioSrcSlaveMethod
+gst_base_audio_src_get_slave_method (GstBaseAudioSrc * src)
+{
+ GstBaseAudioSrcSlaveMethod result;
+
+ g_return_val_if_fail (GST_IS_BASE_AUDIO_SRC (src), -1);
+
+ GST_OBJECT_LOCK (src);
+ result = src->priv->slave_method;
+ GST_OBJECT_UNLOCK (src);
+
+ return result;
+}
+
+static void
+gst_base_audio_src_set_property (GObject * object, guint prop_id,
+ const GValue * value, GParamSpec * pspec)
+{
+ GstBaseAudioSrc *src;
+
+ src = GST_BASE_AUDIO_SRC (object);
+
+ switch (prop_id) {
+ case PROP_BUFFER_TIME:
+ src->buffer_time = g_value_get_int64 (value);
+ break;
+ case PROP_LATENCY_TIME:
+ src->latency_time = g_value_get_int64 (value);
+ break;
+ case PROP_PROVIDE_CLOCK:
+ gst_base_audio_src_set_provide_clock (src, g_value_get_boolean (value));
+ break;
+ case PROP_SLAVE_METHOD:
+ gst_base_audio_src_set_slave_method (src, g_value_get_enum (value));
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+gst_base_audio_src_get_property (GObject * object, guint prop_id,
+ GValue * value, GParamSpec * pspec)
+{
+ GstBaseAudioSrc *src;
+
+ src = GST_BASE_AUDIO_SRC (object);
+
+ switch (prop_id) {
+ case PROP_BUFFER_TIME:
+ g_value_set_int64 (value, src->buffer_time);
+ break;
+ case PROP_LATENCY_TIME:
+ g_value_set_int64 (value, src->latency_time);
+ break;
+ case PROP_ACTUAL_BUFFER_TIME:
+ GST_OBJECT_LOCK (src);
+ if (src->ringbuffer && src->ringbuffer->acquired)
+ g_value_set_int64 (value, src->ringbuffer->spec.buffer_time);
+ else
+ g_value_set_int64 (value, DEFAULT_ACTUAL_BUFFER_TIME);
+ GST_OBJECT_UNLOCK (src);
+ break;
+ case PROP_ACTUAL_LATENCY_TIME:
+ GST_OBJECT_LOCK (src);
+ if (src->ringbuffer && src->ringbuffer->acquired)
+ g_value_set_int64 (value, src->ringbuffer->spec.latency_time);
+ else
+ g_value_set_int64 (value, DEFAULT_ACTUAL_LATENCY_TIME);
+ GST_OBJECT_UNLOCK (src);
+ break;
+ case PROP_PROVIDE_CLOCK:
+ g_value_set_boolean (value, gst_base_audio_src_get_provide_clock (src));
+ break;
+ case PROP_SLAVE_METHOD:
+ g_value_set_enum (value, gst_base_audio_src_get_slave_method (src));
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+gst_base_audio_src_fixate (GstBaseSrc * bsrc, GstCaps * caps)
+{
+ GstStructure *s;
+ gint width, depth;
+
+ s = gst_caps_get_structure (caps, 0);
+
+ /* fields for all formats */
+ gst_structure_fixate_field_nearest_int (s, "rate", 44100);
+ gst_structure_fixate_field_nearest_int (s, "channels", 2);
+ gst_structure_fixate_field_nearest_int (s, "width", 16);
+
+ /* fields for int */
+ if (gst_structure_has_field (s, "depth")) {
+ gst_structure_get_int (s, "width", &width);
+ /* round width to nearest multiple of 8 for the depth */
+ depth = GST_ROUND_UP_8 (width);
+ gst_structure_fixate_field_nearest_int (s, "depth", depth);
+ }
+ if (gst_structure_has_field (s, "signed"))
+ gst_structure_fixate_field_boolean (s, "signed", TRUE);
+ if (gst_structure_has_field (s, "endianness"))
+ gst_structure_fixate_field_nearest_int (s, "endianness", G_BYTE_ORDER);
+}
+
+static gboolean
+gst_base_audio_src_setcaps (GstBaseSrc * bsrc, GstCaps * caps)
+{
+ GstBaseAudioSrc *src = GST_BASE_AUDIO_SRC (bsrc);
+ GstRingBufferSpec *spec;
+
+ spec = &src->ringbuffer->spec;
+
+ spec->buffer_time = src->buffer_time;
+ spec->latency_time = src->latency_time;
+
+ GST_OBJECT_LOCK (src);
+ if (!gst_ring_buffer_parse_caps (spec, caps))
+ {
+ GST_OBJECT_UNLOCK (src);
+ goto parse_error;
+ }
+
+ /* calculate suggested segsize and segtotal */
+ spec->segsize =
+ spec->rate * spec->bytes_per_sample * spec->latency_time / GST_MSECOND;
+ spec->segtotal = spec->buffer_time / spec->latency_time;
+
+ GST_OBJECT_UNLOCK (src);
+
+ GST_DEBUG ("release old ringbuffer");
+
+ gst_ring_buffer_release (src->ringbuffer);
+
+ gst_ring_buffer_debug_spec_buff (spec);
+
+ GST_DEBUG ("acquire new ringbuffer");
+
+ if (!gst_ring_buffer_acquire (src->ringbuffer, spec))
+ goto acquire_error;
+
+ /* calculate actual latency and buffer times */
+ spec->latency_time =
+ spec->segsize * GST_MSECOND / (spec->rate * spec->bytes_per_sample);
+ spec->buffer_time =
+ spec->segtotal * spec->segsize * GST_MSECOND / (spec->rate *
+ spec->bytes_per_sample);
+
+ gst_ring_buffer_debug_spec_buff (spec);
+
+ g_object_notify (G_OBJECT (src), "actual-buffer-time");
+ g_object_notify (G_OBJECT (src), "actual-latency-time");
+
+ return TRUE;
+
+ /* ERRORS */
+parse_error:
+ {
+ GST_DEBUG ("could not parse caps");
+ return FALSE;
+ }
+acquire_error:
+ {
+ GST_DEBUG ("could not acquire ringbuffer");
+ return FALSE;
+ }
+}
+
+static void
+gst_base_audio_src_get_times (GstBaseSrc * bsrc, GstBuffer * buffer,
+ GstClockTime * start, GstClockTime * end)
+{
+ /* no need to sync to a clock here, we schedule the samples based
+ * on our own clock for the moment. */
+ *start = GST_CLOCK_TIME_NONE;
+ *end = GST_CLOCK_TIME_NONE;
+}
+
+static gboolean
+gst_base_audio_src_query (GstBaseSrc * bsrc, GstQuery * query)
+{
+ GstBaseAudioSrc *src = GST_BASE_AUDIO_SRC (bsrc);
+ gboolean res = FALSE;
+
+ switch (GST_QUERY_TYPE (query)) {
+ case GST_QUERY_LATENCY:
+ {
+ GstClockTime min_latency, max_latency;
+ GstRingBufferSpec *spec;
+
+ GST_OBJECT_LOCK (src);
+ if (G_UNLIKELY (src->ringbuffer == NULL
+ || src->ringbuffer->spec.rate == 0)) {
+ GST_OBJECT_UNLOCK (src);
+ goto done;
+ }
+
+ spec = &src->ringbuffer->spec;
+
+ /* we have at least 1 segment of latency */
+ min_latency =
+ gst_util_uint64_scale_int (spec->segsize, GST_SECOND,
+ spec->rate * spec->bytes_per_sample);
+ /* we cannot delay more than the buffersize else we lose data */
+ max_latency =
+ gst_util_uint64_scale_int (spec->segtotal * spec->segsize, GST_SECOND,
+ spec->rate * spec->bytes_per_sample);
+ GST_OBJECT_UNLOCK (src);
+
+ GST_DEBUG_OBJECT (src,
+ "report latency min %" GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
+ GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));
+
+ /* we are always live, the min latency is 1 segment and the max latency is
+ * the complete buffer of segments. */
+ gst_query_set_latency (query, TRUE, min_latency, max_latency);
+
+ res = TRUE;
+ break;
+ }
+ default:
+ res = GST_BASE_SRC_CLASS (parent_class)->query (bsrc, query);
+ break;
+ }
+done:
+ return res;
+}
+
+static gboolean
+gst_base_audio_src_event (GstBaseSrc * bsrc, GstEvent * event)
+{
+ GstBaseAudioSrc *src = GST_BASE_AUDIO_SRC (bsrc);
+ gboolean res;
+
+ res = TRUE;
+
+ switch (GST_EVENT_TYPE (event)) {
+ case GST_EVENT_FLUSH_START:
+ GST_DEBUG_OBJECT (bsrc, "flush-start");
+ gst_ring_buffer_pause (src->ringbuffer);
+ gst_ring_buffer_clear_all (src->ringbuffer);
+ break;
+ case GST_EVENT_FLUSH_STOP:
+ GST_DEBUG_OBJECT (bsrc, "flush-stop");
+ /* always resync on sample after a flush */
+ src->next_sample = -1;
+ gst_ring_buffer_clear_all (src->ringbuffer);
+ break;
+ case GST_EVENT_SEEK:
+ GST_DEBUG_OBJECT (bsrc, "refuse to seek");
+ res = FALSE;
+ break;
+ default:
+ GST_DEBUG_OBJECT (bsrc, "dropping event %p", event);
+ break;
+ }
+ return res;
+}
+
+/* get the next offset in the ringbuffer for reading samples.
+ * If the next sample is too far away, this function will position itself to the
+ * next most recent sample, creating discontinuity */
+static guint64
+gst_base_audio_src_get_offset (GstBaseAudioSrc * src)
+{
+ guint64 sample;
+ gint readseg, segdone, segtotal, sps;
+ gint diff;
+
+ /* assume we can append to the previous sample */
+ sample = src->next_sample;
+
+ sps = src->ringbuffer->samples_per_seg;
+ segtotal = src->ringbuffer->spec.segtotal;
+
+ /* get the currently processed segment */
+ segdone = g_atomic_int_get (&src->ringbuffer->segdone)
+ - src->ringbuffer->segbase;
+
+ if (sample != -1) {
+ GST_DEBUG_OBJECT (src, "at segment %d and sample %" G_GUINT64_FORMAT,
+ segdone, sample);
+ /* figure out the segment and the offset inside the segment where
+ * the sample should be read from. */
+ readseg = sample / sps;
+
+ /* see how far away it is from the read segment, normally segdone (where new
+ * data is written in the ringbuffer) is bigger than readseg (where we are
+ * reading). */
+ diff = segdone - readseg;
+ if (diff >= segtotal) {
+ GST_DEBUG_OBJECT (src, "dropped, align to segment %d", segdone);
+ /* sample would be dropped, position to next playable position */
+ sample = ((guint64) (segdone)) * sps;
+ }
+ } else {
+ /* no previous sample, go to the current position */
+ GST_DEBUG_OBJECT (src, "first sample, align to current %d", segdone);
+ sample = ((guint64) (segdone)) * sps;
+ readseg = segdone;
+ }
+
+ GST_DEBUG_OBJECT (src,
+ "reading from %d, we are at %d, sample %" G_GUINT64_FORMAT, readseg,
+ segdone, sample);
+
+ return sample;
+}
+
+static GstFlowReturn
+gst_base_audio_src_create (GstBaseSrc * bsrc, guint64 offset, guint length,
+ GstBuffer ** outbuf)
+{
+ GstBaseAudioSrc *src = GST_BASE_AUDIO_SRC (bsrc);
+ GstBuffer *buf;
+ guchar *data;
+ guint samples, total_samples;
+ guint64 sample;
+ gint bps;
+ GstRingBuffer *ringbuffer;
+ GstRingBufferSpec *spec;
+ guint read;
+ GstClockTime timestamp, duration;
+ GstClock *clock;
+
+ ringbuffer = src->ringbuffer;
+ spec = &ringbuffer->spec;
+
+ if (G_UNLIKELY (!gst_ring_buffer_is_acquired (ringbuffer)))
+ goto wrong_state;
+
+ bps = spec->bytes_per_sample;
+
+ if ((length == 0 && bsrc->blocksize == 0) || length == -1)
+ /* no length given, use the default segment size */
+ length = spec->segsize;
+ else
+ /* make sure we round down to an integral number of samples */
+ length -= length % bps;
+
+ /* figure out the offset in the ringbuffer */
+ if (G_UNLIKELY (offset != -1)) {
+ sample = offset / bps;
+ /* if a specific offset was given it must be the next sequential
+ * offset we expect or we fail for now. */
+ if (src->next_sample != -1 && sample != src->next_sample)
+ goto wrong_offset;
+ } else {
+ /* calculate the sequentially next sample we need to read. This can jump and
+ * create a DISCONT. */
+ sample = gst_base_audio_src_get_offset (src);
+ }
+
+ GST_DEBUG_OBJECT (src, "reading from sample %" G_GUINT64_FORMAT, sample);
+
+ /* get the number of samples to read */
+ total_samples = samples = length / bps;
+
+ /* FIXME, using a bufferpool would be nice here */
+ buf = gst_buffer_new_and_alloc (length);
+ data = GST_BUFFER_DATA (buf);
+
+ do {
+ read = gst_ring_buffer_read (ringbuffer, sample, data, samples);
+ GST_DEBUG_OBJECT (src, "read %u of %u", read, samples);
+ /* if we read all, we're done */
+ if (read == samples)
+ break;
+
+ /* else something interrupted us and we wait for playing again. */
+ GST_DEBUG_OBJECT (src, "wait playing");
+ if (gst_base_src_wait_playing (bsrc) != GST_FLOW_OK)
+ goto stopped;
+
+ GST_DEBUG_OBJECT (src, "continue playing");
+
+ /* read next samples */
+ sample += read;
+ samples -= read;
+ data += read * bps;
+ } while (TRUE);
+
+ /* mark discontinuity if needed */
+ if (G_UNLIKELY (sample != src->next_sample) && src->next_sample != -1) {
+ GST_WARNING_OBJECT (src,
+ "create DISCONT of %" G_GUINT64_FORMAT " samples at sample %"
+ G_GUINT64_FORMAT, sample - src->next_sample, sample);
+ GST_ELEMENT_WARNING (src, CORE, CLOCK,
+ (_("Can't record audio fast enough")),
+ ("Dropped %" G_GUINT64_FORMAT " samples. This is most likely because "
+ "downstream can't keep up and is consuming samples too slowly.",
+ sample - src->next_sample));
+ GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_DISCONT);
+ }
+
+ src->next_sample = sample + samples;
+
+ /* get the normal timestamp to get the duration. */
+ timestamp = gst_util_uint64_scale_int (sample, GST_SECOND, spec->rate);
+ duration = gst_util_uint64_scale_int (src->next_sample, GST_SECOND,
+ spec->rate) - timestamp;
+
+ GST_OBJECT_LOCK (src);
+ if (!(clock = GST_ELEMENT_CLOCK (src)))
+ goto no_sync;
+
+ if (clock != src->clock) {
+ /* we are slaved, check how to handle this */
+ switch (src->priv->slave_method) {
+ case GST_BASE_AUDIO_SRC_SLAVE_RESAMPLE:
+ /* not implemented, use skew algorithm. This algorithm should
+ * work on the readout pointer and produces more or less samples based
+ * on the clock drift */
+ case GST_BASE_AUDIO_SRC_SLAVE_SKEW:
+ {
+ GstClockTime running_time;
+ GstClockTime base_time;
+ GstClockTime current_time;
+ guint64 running_time_sample;
+ gint running_time_segment;
+ gint last_read_segment;
+ gint segment_skew;
+ gint sps;
+ gint segments_written;
+ gint last_written_segment;
+
+ /* get the amount of segments written from the device by now */
+ segments_written = g_atomic_int_get (&ringbuffer->segdone);
+
+ /* subtract the base to segments_written to get the number of the
+ last written segment in the ringbuffer (one segment written = segment 0) */
+ last_written_segment = segments_written - ringbuffer->segbase - 1;
+
+ /* samples per segment */
+ sps = ringbuffer->samples_per_seg;
+
+ /* get the current time */
+ current_time = gst_clock_get_time (clock);
+
+ /* get the basetime */
+ base_time = GST_ELEMENT_CAST (src)->base_time;
+
+ /* get the running_time */
+ running_time = current_time - base_time;
+
+ /* the running_time converted to a sample (relative to the ringbuffer) */
+ running_time_sample =
+ gst_util_uint64_scale_int (running_time, spec->rate, GST_SECOND);
+
+ /* the segmentnr corrensponding to running_time, round down */
+ running_time_segment = running_time_sample / sps;
+
+ /* the segment currently read from the ringbuffer */
+ last_read_segment = sample / sps;
+
+ /* the skew we have between running_time and the ringbuffertime (last written to) */
+ segment_skew = running_time_segment - last_written_segment;
+
+ GST_DEBUG_OBJECT (bsrc,
+ "\n running_time = %"
+ GST_TIME_FORMAT
+ "\n timestamp = %"
+ GST_TIME_FORMAT
+ "\n running_time_segment = %d"
+ "\n last_written_segment = %d"
+ "\n segment_skew (running time segment - last_written_segment) = %d"
+ "\n last_read_segment = %d",
+ GST_TIME_ARGS (running_time), GST_TIME_ARGS (timestamp),
+ running_time_segment, last_written_segment, segment_skew,
+ last_read_segment);
+
+ /* Resync the ringbuffer if:
+ *
+ * 1. We are more than the length of the ringbuffer behind.
+ * The length of the ringbuffer then gets to dictate
+ * the threshold for what is concidered "too late"
+ *
+ * 2. If this is our first buffer.
+ * We know that we should catch up to running_time
+ * the first time we are ran.
+ */
+ if ((segment_skew >= ringbuffer->spec.segtotal) ||
+ (last_read_segment == 0)) {
+ gint new_read_segment;
+ gint segment_diff;
+ guint64 new_sample;
+
+ /* the difference between running_time and the last written segment */
+ segment_diff = running_time_segment - last_written_segment;
+
+ /* advance the ringbuffer */
+ gst_ring_buffer_advance (ringbuffer, segment_diff);
+
+ /* we move the new read segment to the last known written segment */
+ new_read_segment =
+ g_atomic_int_get (&ringbuffer->segdone) - ringbuffer->segbase;
+
+ /* we calculate the new sample value */
+ new_sample = ((guint64) new_read_segment) * sps;
+
+ /* and get the relative time to this -> our new timestamp */
+ timestamp =
+ gst_util_uint64_scale_int (new_sample, GST_SECOND, spec->rate);
+
+ /* we update the next sample accordingly */
+ src->next_sample = new_sample + samples;
+
+ GST_DEBUG_OBJECT (bsrc,
+ "Timeshifted the ringbuffer with %d segments: "
+ "Updating the timestamp to %" GST_TIME_FORMAT ", "
+ "and src->next_sample to %" G_GUINT64_FORMAT, segment_diff,
+ GST_TIME_ARGS (timestamp), src->next_sample);
+ }
+ break;
+ }
+ case GST_BASE_AUDIO_SRC_SLAVE_RETIMESTAMP:
+ {
+ GstClockTime base_time, latency;
+
+ /* We are slaved to another clock, take running time of the pipeline clock and
+ * timestamp against it. Somebody else in the pipeline should figure out the
+ * clock drift. We keep the duration we calculated above. */
+ timestamp = gst_clock_get_time (clock);
+ base_time = GST_ELEMENT_CAST (src)->base_time;
+
+ if (GST_CLOCK_DIFF (timestamp, base_time) < 0)
+ timestamp -= base_time;
+ else
+ timestamp = 0;
+
+ /* subtract latency */
+ latency =
+ gst_util_uint64_scale_int (total_samples, GST_SECOND, spec->rate);
+ if (timestamp > latency)
+ timestamp -= latency;
+ else
+ timestamp = 0;
+ }
+ case GST_BASE_AUDIO_SRC_SLAVE_NONE:
+ break;
+ }
+ } else {
+ GstClockTime base_time;
+
+ /* to get the timestamp against the clock we also need to add our offset */
+ timestamp = gst_audio_clock_adjust (clock, timestamp);
+
+ /* we are not slaved, subtract base_time */
+ base_time = GST_ELEMENT_CAST (src)->base_time;
+
+ if (GST_CLOCK_DIFF (timestamp, base_time) < 0) {
+ timestamp -= base_time;
+ GST_LOG_OBJECT (src,
+ "buffer timestamp %" GST_TIME_FORMAT " (base_time %" GST_TIME_FORMAT
+ ")", GST_TIME_ARGS (timestamp), GST_TIME_ARGS (base_time));
+ } else {
+ GST_LOG_OBJECT (src,
+ "buffer timestamp 0, ts %" GST_TIME_FORMAT " <= base_time %"
+ GST_TIME_FORMAT, GST_TIME_ARGS (timestamp),
+ GST_TIME_ARGS (base_time));
+ timestamp = 0;
+ }
+ }
+
+no_sync:
+ GST_OBJECT_UNLOCK (src);
+
+ GST_BUFFER_TIMESTAMP (buf) = timestamp;
+ GST_BUFFER_DURATION (buf) = duration;
+ GST_BUFFER_OFFSET (buf) = sample;
+ GST_BUFFER_OFFSET_END (buf) = sample + samples;
+
+ *outbuf = buf;
+
+ return GST_FLOW_OK;
+
+ /* ERRORS */
+wrong_state:
+ {
+ GST_DEBUG_OBJECT (src, "ringbuffer in wrong state");
+ return GST_FLOW_WRONG_STATE;
+ }
+wrong_offset:
+ {
+ GST_ELEMENT_ERROR (src, RESOURCE, SEEK,
+ (NULL), ("resource can only be operated on sequentially but offset %"
+ G_GUINT64_FORMAT " was given", offset));
+ return GST_FLOW_ERROR;
+ }
+stopped:
+ {
+ gst_buffer_unref (buf);
+ GST_DEBUG_OBJECT (src, "ringbuffer stopped");
+ return GST_FLOW_WRONG_STATE;
+ }
+}
+
+/**
+ * gst_base_audio_src_create_ringbuffer:
+ * @src: a #GstBaseAudioSrc.
+ *
+ * Create and return the #GstRingBuffer for @src. This function will call the
+ * ::create_ringbuffer vmethod and will set @src as the parent of the returned
+ * buffer (see gst_object_set_parent()).
+ *
+ * Returns: The new ringbuffer of @src.
+ */
+GstRingBuffer *
+gst_base_audio_src_create_ringbuffer (GstBaseAudioSrc * src)
+{
+ GstBaseAudioSrcClass *bclass;
+ GstRingBuffer *buffer = NULL;
+
+ bclass = GST_BASE_AUDIO_SRC_GET_CLASS (src);
+ if (bclass->create_ringbuffer)
+ buffer = bclass->create_ringbuffer (src);
+
+ if (G_LIKELY (buffer))
+ gst_object_set_parent (GST_OBJECT_CAST (buffer), GST_OBJECT_CAST (src));
+
+ return buffer;
+}
+
+static GstStateChangeReturn
+gst_base_audio_src_change_state (GstElement * element,
+ GstStateChange transition)
+{
+ GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
+ GstBaseAudioSrc *src = GST_BASE_AUDIO_SRC (element);
+
+ switch (transition) {
+ case GST_STATE_CHANGE_NULL_TO_READY:
+ GST_DEBUG_OBJECT (src, "NULL->READY");
+ GST_OBJECT_LOCK (src);
+ if (src->ringbuffer == NULL) {
+ gst_audio_clock_reset (GST_AUDIO_CLOCK (src->clock), 0);
+ src->ringbuffer = gst_base_audio_src_create_ringbuffer (src);
+ }
+ GST_OBJECT_UNLOCK (src);
+ if (!gst_ring_buffer_open_device (src->ringbuffer))
+ goto open_failed;
+ break;
+ case GST_STATE_CHANGE_READY_TO_PAUSED:
+ GST_DEBUG_OBJECT (src, "READY->PAUSED");
+ src->next_sample = -1;
+ gst_ring_buffer_set_flushing (src->ringbuffer, FALSE);
+ gst_ring_buffer_may_start (src->ringbuffer, FALSE);
+ /* Only post clock-provide messages if this is the clock that
+ * we've created. If the subclass has overriden it the subclass
+ * should post this messages whenever necessary */
+ if (src->clock && GST_IS_AUDIO_CLOCK (src->clock) &&
+ GST_AUDIO_CLOCK_CAST (src->clock)->func ==
+ (GstAudioClockGetTimeFunc) gst_base_audio_src_get_time)
+ gst_element_post_message (element,
+ gst_message_new_clock_provide (GST_OBJECT_CAST (element),
+ src->clock, TRUE));
+ break;
+ case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
+ GST_DEBUG_OBJECT (src, "PAUSED->PLAYING");
+ gst_ring_buffer_may_start (src->ringbuffer, TRUE);
+ break;
+ case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
+ GST_DEBUG_OBJECT (src, "PLAYING->PAUSED");
+ gst_ring_buffer_may_start (src->ringbuffer, FALSE);
+ gst_ring_buffer_pause (src->ringbuffer);
+ break;
+ case GST_STATE_CHANGE_PAUSED_TO_READY:
+ GST_DEBUG_OBJECT (src, "PAUSED->READY");
+ /* Only post clock-lost messages if this is the clock that
+ * we've created. If the subclass has overriden it the subclass
+ * should post this messages whenever necessary */
+ if (src->clock && GST_IS_AUDIO_CLOCK (src->clock) &&
+ GST_AUDIO_CLOCK_CAST (src->clock)->func ==
+ (GstAudioClockGetTimeFunc) gst_base_audio_src_get_time)
+ gst_element_post_message (element,
+ gst_message_new_clock_lost (GST_OBJECT_CAST (element), src->clock));
+ gst_ring_buffer_set_flushing (src->ringbuffer, TRUE);
+ break;
+ default:
+ break;
+ }
+
+ ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+
+ switch (transition) {
+ case GST_STATE_CHANGE_PAUSED_TO_READY:
+ GST_DEBUG_OBJECT (src, "PAUSED->READY");
+ gst_ring_buffer_release (src->ringbuffer);
+ break;
+ case GST_STATE_CHANGE_READY_TO_NULL:
+ GST_DEBUG_OBJECT (src, "READY->NULL");
+ gst_ring_buffer_close_device (src->ringbuffer);
+ GST_OBJECT_LOCK (src);
+ gst_object_unparent (GST_OBJECT_CAST (src->ringbuffer));
+ src->ringbuffer = NULL;
+ GST_OBJECT_UNLOCK (src);
+ break;
+ default:
+ break;
+ }
+
+ return ret;
+
+ /* ERRORS */
+open_failed:
+ {
+ /* subclass must post a meaningfull error message */
+ GST_DEBUG_OBJECT (src, "open failed");
+ return GST_STATE_CHANGE_FAILURE;
+ }
+
+}