/* GStreamer Tuner
* Copyright (C) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
*
* tuner.c: tuner design virtual class function wrappers
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "tuner.h"
#include <string.h>
/**
* SECTION:gsttuner
* @short_description: Interface for elements providing tuner operations
*
* <refsect2>
* <para>
* The GstTuner interface is provided by elements that have the ability to
* tune into multiple input signals, for example TV or radio capture cards.
* </para><para>
* The interpretation of 'tuning into' an input stream depends on the element
* implementing the interface. For v4lsrc, it might imply selection of an
* input source and/or frequency to be configured on a TV card. Another
* GstTuner implementation might be to allow selection of an active input pad
* from multiple input pads.
* </para><para>
* That said, the GstTuner interface functions are biased toward the
* TV capture scenario.
* </para><para>
* The general parameters provided are for configuration are:
* <itemizedlist>
* <listitem>Selection of a current #GstTunerChannel. The current channel
* represents the input source (e.g. Composite, S-Video etc for TV capture).
* </listitem>
* <listitem>The #GstTunerNorm for the channel. The norm chooses the
* interpretation of the incoming signal for the current channel. For example,
* PAL or NTSC, or more specific variants there-of.
* </listitem>
* <listitem>Channel frequency. If the current channel has the ability to tune
* between multiple frequencies (if it has the GST_TUNER_CHANNEL_FREQUENCY flag)
* then the frequency can be changed/retrieved via the
* gst_tuner_set_frequency() and gst_tuner_get_frequency() methods.
* </listitem>
* </itemizedlist>
* </para>
* <para>
* Where applicable, the signal strength can be retrieved and/or monitored
* via a signal.
* </para>
* </refsect2>
*/
/* FIXME 0.11: check if we need to add API for sometimes-supportedness
* (aka making up for GstImplementsInterface removal) */
/* FIXME 0.11: replace signals with messages (+ make API thread-safe) */
enum
{
NORM_CHANGED,
CHANNEL_CHANGED,
FREQUENCY_CHANGED,
SIGNAL_CHANGED,
LAST_SIGNAL
};
static guint gst_tuner_signals[LAST_SIGNAL] = { 0 };
G_DEFINE_INTERFACE (GstTuner, gst_tuner, G_TYPE_INVALID);
static void
gst_tuner_default_init (GstTunerInterface * iface)
{
static gboolean initialized = FALSE;
if (!initialized) {
/**
* GstTuner::norm-changed:
* @tuner: The element providing the GstTuner interface
* @norm: The new configured norm.
*
* Reports that the current #GstTunerNorm has changed.
*/
gst_tuner_signals[NORM_CHANGED] =
g_signal_new ("norm-changed",
GST_TYPE_TUNER, G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstTunerInterface, norm_changed),
NULL, NULL,
g_cclosure_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_TUNER_NORM);
/**
* GstTuner::channel-changed:
* @tuner: The element providing the GstTuner interface
* @channel: The new configured channel.
*
* Reports that the current #GstTunerChannel has changed.
*/
gst_tuner_signals[CHANNEL_CHANGED] =
g_signal_new ("channel-changed",
GST_TYPE_TUNER, G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstTunerInterface, channel_changed),
NULL, NULL,
g_cclosure_marshal_VOID__OBJECT, G_TYPE_NONE, 1,
GST_TYPE_TUNER_CHANNEL);
/**
* GstTuner::frequency-changed:
* @tuner: The element providing the GstTuner interface
* @frequency: The new frequency (an unsigned long)
*
* Reports that the current frequency has changed.
*/
gst_tuner_signals[FREQUENCY_CHANGED] =
g_signal_new ("frequency-changed",
GST_TYPE_TUNER, G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstTunerInterface, frequency_changed),
NULL, NULL,
g_cclosure_marshal_generic, G_TYPE_NONE, 2, GST_TYPE_TUNER_CHANNEL,
G_TYPE_ULONG);
/**
* GstTuner::signal-changed:
* @tuner: The element providing the GstTuner interface
* @channel: The current #GstTunerChannel
* @signal: The new signal strength (an integer)
*
* Reports that the signal strength has changed.
*
* See Also: gst_tuner_signal_strength()
*/
gst_tuner_signals[SIGNAL_CHANGED] =
g_signal_new ("signal-changed",
GST_TYPE_TUNER, G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstTunerInterface, signal_changed),
NULL, NULL,
g_cclosure_marshal_generic, G_TYPE_NONE, 2, GST_TYPE_TUNER_CHANNEL,
G_TYPE_INT);
initialized = TRUE;
}
/* default virtual functions */
iface->list_channels = NULL;
iface->set_channel = NULL;
iface->get_channel = NULL;
iface->list_norms = NULL;
iface->set_norm = NULL;
iface->get_norm = NULL;
iface->set_frequency = NULL;
iface->get_frequency = NULL;
iface->signal_strength = NULL;
}
/**
* gst_tuner_list_channels:
* @tuner: the #GstTuner (a #GstElement) to get the channels from.
*
* Retrieve a #GList of #GstTunerChannels available
* (e.g. 'composite', 's-video', ...) from the given tuner object.
*
* Returns: A list of channels available on this tuner. The list is
* owned by the GstTuner and must not be freed.
*/
const GList *
gst_tuner_list_channels (GstTuner * tuner)
{
GstTunerInterface *iface;
g_return_val_if_fail (GST_IS_TUNER (tuner), NULL);
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->list_channels) {
return iface->list_channels (tuner);
}
return NULL;
}
/**
* gst_tuner_set_channel:
* @tuner: the #GstTuner (a #GstElement) that owns the channel.
* @channel: the channel to tune to.
*
* Tunes the object to the given channel, which should be one of the
* channels returned by gst_tuner_list_channels().
*/
void
gst_tuner_set_channel (GstTuner * tuner, GstTunerChannel * channel)
{
GstTunerInterface *iface;
g_return_if_fail (GST_IS_TUNER (tuner));
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->set_channel) {
iface->set_channel (tuner, channel);
}
}
/**
* gst_tuner_get_channel:
* @tuner: the #GstTuner (a #GstElement) to get the current channel from.
*
* Retrieve the current channel from the tuner.
*
* Returns: the current channel of the tuner object.
*/
GstTunerChannel *
gst_tuner_get_channel (GstTuner * tuner)
{
GstTunerInterface *iface;
g_return_val_if_fail (GST_IS_TUNER (tuner), NULL);
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->get_channel) {
return iface->get_channel (tuner);
}
return NULL;
}
/**
* gst_tuner_list_norms:
* @tuner: the #GstTuner (*a #GstElement) to get the list of norms from.
*
* Retrieve a GList of available #GstTunerNorm settings for the currently
* tuned channel on the given tuner object.
*
* Returns: A list of norms available on the current channel for this
* tuner object. The list is owned by the GstTuner and must not
* be freed.
*/
const GList *
gst_tuner_list_norms (GstTuner * tuner)
{
GstTunerInterface *iface;
g_return_val_if_fail (GST_IS_TUNER (tuner), NULL);
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->list_norms) {
return iface->list_norms (tuner);
}
return NULL;
}
/**
* gst_tuner_set_norm:
* @tuner: the #GstTuner (a #GstElement) to set the norm on.
* @norm: the norm to use for the current channel.
*
* Changes the video norm on this tuner to the given norm, which should be
* one of the norms returned by gst_tuner_list_norms().
*/
void
gst_tuner_set_norm (GstTuner * tuner, GstTunerNorm * norm)
{
GstTunerInterface *iface;
g_return_if_fail (GST_IS_TUNER (tuner));
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->set_norm) {
iface->set_norm (tuner, norm);
}
}
/**
* gst_tuner_get_norm:
* @tuner: the #GstTuner (a #GstElement) to get the current norm from.
*
* Get the current video norm from the given tuner object for the
* currently selected channel.
*
* Returns: the current norm.
*/
GstTunerNorm *
gst_tuner_get_norm (GstTuner * tuner)
{
GstTunerInterface *iface;
g_return_val_if_fail (GST_IS_TUNER (tuner), NULL);
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->get_norm) {
return iface->get_norm (tuner);
}
return NULL;
}
/**
* gst_tuner_set_frequency:
* @tuner: The #GstTuner (a #GstElement) that owns the given channel.
* @channel: The #GstTunerChannel to set the frequency on.
* @frequency: The frequency to tune in to.
*
* Sets a tuning frequency on the given tuner/channel. Note that this
* requires the given channel to be a "tuning" channel, which can be
* checked using GST_TUNER_CHANNEL_HAS_FLAG (), with the proper flag
* being GST_TUNER_CHANNEL_FREQUENCY.
*
* The frequency is in Hz, with minimum steps indicated by the
* frequency_multiplicator provided in the #GstTunerChannel. The
* valid range is provided in the min_frequency and max_frequency properties
* of the #GstTunerChannel.
*/
void
gst_tuner_set_frequency (GstTuner * tuner,
GstTunerChannel * channel, gulong frequency)
{
GstTunerInterface *iface;
g_return_if_fail (GST_IS_TUNER (tuner));
g_return_if_fail (GST_IS_TUNER_CHANNEL (channel));
g_return_if_fail (GST_TUNER_CHANNEL_HAS_FLAG (channel,
GST_TUNER_CHANNEL_FREQUENCY));
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->set_frequency) {
iface->set_frequency (tuner, channel, frequency);
}
}
/**
* gst_tuner_get_frequency:
* @tuner: The #GstTuner (a #GstElement) that owns the given channel.
* @channel: The #GstTunerChannel to retrieve the frequency from.
*
* Retrieve the current frequency from the given channel. As for
* gst_tuner_set_frequency(), the #GstTunerChannel must support frequency
* operations, as indicated by the GST_TUNER_CHANNEL_FREQUENCY flag.
*
* Returns: The current frequency, or 0 on error.
*/
gulong
gst_tuner_get_frequency (GstTuner * tuner, GstTunerChannel * channel)
{
GstTunerInterface *iface;
g_return_val_if_fail (GST_IS_TUNER (tuner), 0);
g_return_val_if_fail (GST_IS_TUNER_CHANNEL (channel), 0);
g_return_val_if_fail (GST_TUNER_CHANNEL_HAS_FLAG (channel,
GST_TUNER_CHANNEL_FREQUENCY), 0);
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->get_frequency) {
return iface->get_frequency (tuner, channel);
}
return 0;
}
/**
* gst_tuner_signal_strength:
* @tuner: the #GstTuner (a #GstElement) that owns the given channel.
* @channel: the #GstTunerChannel to get the signal strength from.
*
* Get the strength of the signal on this channel. Note that this
* requires the current channel to be a "tuning" channel, i.e. a
* channel on which frequency can be set. This can be checked using
* GST_TUNER_CHANNEL_HAS_FLAG (), and the appropriate flag to check
* for is GST_TUNER_CHANNEL_FREQUENCY.
*
* The valid range of the signal strength is indicated in the
* min_signal and max_signal properties of the #GstTunerChannel.
*
* Returns: Signal strength, or 0 on error.
*/
gint
gst_tuner_signal_strength (GstTuner * tuner, GstTunerChannel * channel)
{
GstTunerInterface *iface;
g_return_val_if_fail (GST_IS_TUNER (tuner), 0);
g_return_val_if_fail (GST_IS_TUNER_CHANNEL (channel), 0);
g_return_val_if_fail (GST_TUNER_CHANNEL_HAS_FLAG (channel,
GST_TUNER_CHANNEL_FREQUENCY), 0);
iface = GST_TUNER_GET_INTERFACE (tuner);
if (iface->signal_strength) {
return iface->signal_strength (tuner, channel);
}
return 0;
}
/**
* gst_tuner_find_norm_by_name:
* @tuner: A #GstTuner instance
* @norm: A string containing the name of a #GstTunerNorm
*
* Look up a #GstTunerNorm by name.
*
* Returns: A #GstTunerNorm, or NULL if no norm with the provided name
* is available.
*/
GstTunerNorm *
gst_tuner_find_norm_by_name (GstTuner * tuner, gchar * norm)
{
GList *walk;
g_return_val_if_fail (GST_IS_TUNER (tuner), NULL);
g_return_val_if_fail (norm != NULL, NULL);
walk = (GList *) gst_tuner_list_norms (tuner);
while (walk) {
if (strcmp (GST_TUNER_NORM (walk->data)->label, norm) == 0)
return GST_TUNER_NORM (walk->data);
walk = g_list_next (walk);
}
return NULL;
}
/**
* gst_tuner_find_channel_by_name:
* @tuner: A #GstTuner instance
* @channel: A string containing the name of a #GstTunerChannel
*
* Look up a #GstTunerChannel by name.
*
* Returns: A #GstTunerChannel, or NULL if no channel with the provided name
* is available.
*/
GstTunerChannel *
gst_tuner_find_channel_by_name (GstTuner * tuner, gchar * channel)
{
GList *walk;
g_return_val_if_fail (GST_IS_TUNER (tuner), NULL);
g_return_val_if_fail (channel != NULL, NULL);
walk = (GList *) gst_tuner_list_channels (tuner);
while (walk) {
if (strcmp (GST_TUNER_CHANNEL (walk->data)->label, channel) == 0)
return GST_TUNER_CHANNEL (walk->data);
walk = g_list_next (walk);
}
return NULL;
}
/**
* gst_tuner_channel_changed:
* @tuner: A #GstTuner instance
* @channel: A #GstTunerChannel instance
*
* Called by elements implementing the #GstTuner interface when the
* current channel changes. Fires the #GstTuner::channel-changed signal.
*/
void
gst_tuner_channel_changed (GstTuner * tuner, GstTunerChannel * channel)
{
g_return_if_fail (GST_IS_TUNER (tuner));
g_return_if_fail (GST_IS_TUNER_CHANNEL (channel));
g_signal_emit (G_OBJECT (tuner),
gst_tuner_signals[CHANNEL_CHANGED], 0, channel);
}
/**
* gst_tuner_norm_changed:
* @tuner: A #GstTuner instance
* @norm: A #GstTunerNorm instance
*
* Called by elements implementing the #GstTuner interface when the
* current norm changes. Fires the #GstTuner::norm-changed signal.
*
*/
void
gst_tuner_norm_changed (GstTuner * tuner, GstTunerNorm * norm)
{
g_return_if_fail (GST_IS_TUNER (tuner));
g_return_if_fail (GST_IS_TUNER_NORM (norm));
g_signal_emit (G_OBJECT (tuner), gst_tuner_signals[NORM_CHANGED], 0, norm);
}
/**
* gst_tuner_frequency_changed:
* @tuner: A #GstTuner instance
* @channel: The current #GstTunerChannel
* @frequency: The new frequency setting
*
* Called by elements implementing the #GstTuner interface when the
* configured frequency changes. Fires the #GstTuner::frequency-changed
* signal on the tuner, and the #GstTunerChannel::frequency-changed signal
* on the channel.
*/
void
gst_tuner_frequency_changed (GstTuner * tuner,
GstTunerChannel * channel, gulong frequency)
{
g_return_if_fail (GST_IS_TUNER (tuner));
g_return_if_fail (GST_IS_TUNER_CHANNEL (channel));
g_signal_emit (G_OBJECT (tuner),
gst_tuner_signals[FREQUENCY_CHANGED], 0, channel, frequency);
g_signal_emit_by_name (G_OBJECT (channel), "frequency_changed", frequency);
}
/**
* gst_tuner_signal_changed:
* @tuner: A #GstTuner instance
* @channel: The current #GstTunerChannel
* @signal: The new signal strength
*
* Called by elements implementing the #GstTuner interface when the
* incoming signal strength changes. Fires the #GstTuner::signal-changed
* signal on the tuner and the #GstTunerChannel::signal-changed signal on
* the channel.
*/
void
gst_tuner_signal_changed (GstTuner * tuner,
GstTunerChannel * channel, gint signal)
{
g_return_if_fail (GST_IS_TUNER (tuner));
g_return_if_fail (GST_IS_TUNER_CHANNEL (channel));
g_signal_emit (G_OBJECT (tuner),
gst_tuner_signals[SIGNAL_CHANGED], 0, channel, signal);
g_signal_emit_by_name (G_OBJECT (channel), "signal_changed", signal);
}