Parametrized Composite Mixer (#84)

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## What is the current behavior you want to change?

The previous implementation had fixed values for **width**, **height**,
and **framerate** within the compositor's C class, which limited
flexibility and required code changes for adjustment.



## What is the new behavior provided by this change?

With this change, the **width**, **height**, and **framerate** values
for the compositor are now optionally parameterized. When creating a
Composite in Kurento, these values can be set directly; if a value of 0
is passed, the compositor defaults to a configuration stored in
Composite.conf.ini (located at
_kurento/server/module-elements/src/server/config/_).



## How has this been tested?

This feature was tested using automated unit tests in the Kurento
testing framework. The main tests, composite_setup and
composite_param_setup, validated media flow within a composite setup
both with parameters and without. They covered various configurations
(including width, height, and framerate settings) and verified that both
audio and video media were flowing as expected. The test suite ran
successfully, with 100% of tests passing.



## Types of changes
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Put an 'x' in all the boxes that apply:
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- [ ] Bug fix (non-breaking change which fixes an issue)
- [X] New feature / enhancement (non-breaking change which improves the
project)
- [ ] Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] My change requires a change to the documentation
- [ ] My change requires a change in other repository <!-- Explain which
one -->


## Checklist
<!--
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apply.
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- [X] I have read the [Contribution
Guidelines](https://github.com/Kurento/kurento/blob/main/.github/CONTRIBUTING.md)
- [X] I have added an explanation of what the changes do and why they
should be included
- [X] I have written new tests for the changes, as applicable, and have
successfully run them locally

server/module-elements/src/gst-plugins/kmscompositemixer.c

@@ -40,12 +40,12 @@ GST_DEBUG_CATEGORY_STATIC (kms_composite_mixer_debug_category);
 #define GST_CAT_DEFAULT kms_composite_mixer_debug_category
 
 #define KMS_COMPOSITE_MIXER_GET_PRIVATE(obj) (\
-  G_TYPE_INSTANCE_GET_PRIVATE (               \
-    (obj),                                    \
-    KMS_TYPE_COMPOSITE_MIXER,                 \
-    KmsCompositeMixerPrivate                  \
-  )                                           \
-)
+    G_TYPE_INSTANCE_GET_PRIVATE (               \
+        (obj),                                    \
+        KMS_TYPE_COMPOSITE_MIXER,                 \
+        KmsCompositeMixerPrivate                  \
+                                )                                           \
+                                             )
 
 #define AUDIO_SINK_PAD_PREFIX_COMP "audio_sink_"
 #define VIDEO_SINK_PAD_PREFIX_COMP "video_sink_"
@@ -97,7 +97,7 @@ struct _KmsCompositeMixerPrivate
   KmsLoop *loop;
   GRecMutex mutex;
   gint n_elems;
-  gint output_width, output_height;
+  gint output_width, output_height, output_framerate;
 };
 
 /* class initialization */
@@ -131,7 +131,7 @@ typedef struct _KmsCompositeMixerData
   kms_ref_struct_unref (KMS_REF_STRUCT_CAST (data))
 
 static void
-kms_destroy_composite_mixer_data (KmsCompositeMixerData * data)
+kms_destroy_composite_mixer_data (KmsCompositeMixerData *data)
 {
   g_slice_free (KmsCompositeMixerData, data);
 }
@@ -211,7 +211,7 @@ kms_composite_mixer_recalculate_sizes (gpointer data)
 }
 
 static gboolean
-remove_elements_from_pipeline (KmsCompositeMixerData * port_data)
+remove_elements_from_pipeline (KmsCompositeMixerData *port_data)
 {
   KmsCompositeMixer *self = port_data->mixer;
 
@@ -259,7 +259,7 @@ remove_elements_from_pipeline (KmsCompositeMixerData * port_data)
 }
 
 static GstPadProbeReturn
-cb_EOS_received (GstPad * pad, GstPadProbeInfo * info, gpointer data)
+cb_EOS_received (GstPad *pad, GstPadProbeInfo *info, gpointer data)
 {
   KmsCompositeMixerData *port_data = (KmsCompositeMixerData *) data;
   KmsCompositeMixer *self = port_data->mixer;
@@ -296,7 +296,7 @@ cb_EOS_received (GstPad * pad, GstPadProbeInfo * info, gpointer data)
 }
 
 static GstPadProbeReturn
-cb_latency (GstPad * pad, GstPadProbeInfo * info, gpointer data)
+cb_latency (GstPad *pad, GstPadProbeInfo *info, gpointer data)
 {
   if (GST_QUERY_TYPE (GST_PAD_PROBE_INFO_QUERY (info)) != GST_QUERY_LATENCY) {
     return GST_PAD_PROBE_OK;
@@ -358,6 +358,7 @@ kms_composite_mixer_port_data_destroy (gpointer data)
         self->priv->n_elems--;
         kms_composite_mixer_recalculate_sizes (self);
       }
+
       KMS_COMPOSITE_MIXER_UNLOCK (self);
 
       if (!result) {
@@ -379,6 +380,7 @@ kms_composite_mixer_port_data_destroy (gpointer data)
             (GDestroyNotify) kms_ref_struct_unref);
       }
     }
+
     gst_element_unlink (port_data->capsfilter, port_data->tee);
     g_object_unref (pad);
   } else {
@@ -394,6 +396,7 @@ kms_composite_mixer_port_data_destroy (gpointer data)
     if (port_data->link_probe_id > 0) {
       gst_pad_remove_probe (port_data->tee_sink_pad, port_data->link_probe_id);
     }
+
     KMS_COMPOSITE_MIXER_UNLOCK (self);
 
     gst_element_unlink (port_data->capsfilter, port_data->tee);
@@ -423,8 +426,8 @@ kms_composite_mixer_port_data_destroy (gpointer data)
 }
 
 static GstPadProbeReturn
-link_to_videomixer (GstPad * pad, GstPadProbeInfo * info,
-    KmsCompositeMixerData * data)
+link_to_videomixer (GstPad *pad, GstPadProbeInfo *info,
+    KmsCompositeMixerData *data)
 {
   GstPadTemplate *sink_pad_template;
   KmsCompositeMixer *mixer;
@@ -502,7 +505,7 @@ create_gint (gint value)
 }
 
 static void
-kms_composite_mixer_unhandle_port (KmsBaseHub * mixer, gint id)
+kms_composite_mixer_unhandle_port (KmsBaseHub *mixer, gint id)
 {
   KmsCompositeMixer *self = KMS_COMPOSITE_MIXER (mixer);
 
@@ -519,7 +522,7 @@ kms_composite_mixer_unhandle_port (KmsBaseHub * mixer, gint id)
 }
 
 static KmsCompositeMixerData *
-kms_composite_mixer_port_data_create (KmsCompositeMixer * mixer, gint id)
+kms_composite_mixer_port_data_create (KmsCompositeMixer *mixer, gint id)
 {
   KmsCompositeMixerData *data;
   GstPad *tee_src;
@@ -533,15 +536,13 @@ kms_composite_mixer_port_data_create (KmsCompositeMixer * mixer, gint id)
   data->removing = FALSE;
   data->eos_managed = FALSE;
 
-
   // Link AUDIO input
 
   padname = g_strdup_printf (AUDIO_SINK_PAD, data->id);
   kms_base_hub_link_audio_sink (KMS_BASE_HUB (mixer), data->id,
       mixer->priv->audiomixer, padname, FALSE);
   g_free (padname);
 
-
   // Link VIDEO input
 
   data->tee = kms_utils_element_factory_make ("tee", PLUGIN_NAME);
@@ -564,6 +565,7 @@ kms_composite_mixer_port_data_create (KmsCompositeMixer * mixer, gint id)
       gst_caps_new_simple ("video/x-raw",
       "width", G_TYPE_INT, mixer->priv->output_width,
       "height", G_TYPE_INT, mixer->priv->output_height,
+      "framerate", GST_TYPE_FRACTION, mixer->priv->output_framerate, 1,
       "pixel-aspect-ratio", GST_TYPE_FRACTION, 1, 1, NULL);
   g_object_set (data->capsfilter, "caps", filtercaps, NULL);
   gst_caps_unref (filtercaps);
@@ -581,48 +583,50 @@ kms_composite_mixer_port_data_create (KmsCompositeMixer * mixer, gint id)
       "sink");
   g_object_unref (tee_src);
 
-
   data->link_probe_id = gst_pad_add_probe (data->tee_sink_pad,
       GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM | GST_PAD_PROBE_TYPE_BLOCK,
       (GstPadProbeCallback) link_to_videomixer,
       KMS_COMPOSITE_MIXER_REF (data), (GDestroyNotify) kms_ref_struct_unref);
 
-
   // Link DATA input
 
   kms_base_hub_link_data_sink (KMS_BASE_HUB (mixer), data->id,
       mixer->priv->datamixer_sink, "sink_%u", TRUE);
 
-
   return data;
 }
 
 static gint
-get_stream_id_from_padname (const gchar * name)
+get_stream_id_from_padname (const gchar *name)
 {
   gint64 id;
 
-  if (name == NULL)
+  if (name == NULL) {
     return -1;
+  }
 
-  if (!g_str_has_prefix (name, AUDIO_SRC_PAD_PREFIX))
+  if (!g_str_has_prefix (name, AUDIO_SRC_PAD_PREFIX)) {
     return -1;
+  }
 
   id = g_ascii_strtoll (name + LENGTH_AUDIO_SRC_PAD_PREFIX, NULL, 10);
-  if (id > G_MAXINT)
+
+  if (id > G_MAXINT) {
     return -1;
+  }
 
   return id;
 }
 
 static void
-pad_added_cb (GstElement * element, GstPad * pad, gpointer data)
+pad_added_cb (GstElement *element, GstPad *pad, gpointer data)
 {
   gint id;
   KmsCompositeMixer *self = KMS_COMPOSITE_MIXER (data);
 
-  if (gst_pad_get_direction (pad) != GST_PAD_SRC)
+  if (gst_pad_get_direction (pad) != GST_PAD_SRC) {
     return;
+  }
 
   id = get_stream_id_from_padname (GST_OBJECT_NAME (pad));
 
@@ -636,14 +640,13 @@ pad_added_cb (GstElement * element, GstPad * pad, gpointer data)
 }
 
 static void
-pad_removed_cb (GstElement * element, GstPad * pad, gpointer data)
+pad_removed_cb (GstElement *element, GstPad *pad, gpointer data)
 {
   GST_DEBUG ("Removed pad %" GST_PTR_FORMAT, pad);
 }
 
 static gint
-kms_composite_mixer_handle_port (KmsBaseHub * mixer,
-    GstElement * mixer_end_point)
+kms_composite_mixer_handle_port (KmsBaseHub *mixer, GstElement *mixer_end_point)
 {
   KmsCompositeMixer *self = KMS_COMPOSITE_MIXER (mixer);
   KmsCompositeMixerData *port_data;
@@ -697,7 +700,8 @@ kms_composite_mixer_handle_port (KmsBaseHub * mixer,
           gst_caps_new_simple ("video/x-raw",
           "width", G_TYPE_INT, self->priv->output_width,
           "height", G_TYPE_INT, self->priv->output_height,
-          "framerate", GST_TYPE_FRACTION, 15, 1, NULL);
+          "framerate", GST_TYPE_FRACTION, self->priv->output_framerate, 1,
+          NULL);
       g_object_set (G_OBJECT (capsfilter), "caps", filtercaps, NULL);
       gst_caps_unref (filtercaps);
 
@@ -721,6 +725,7 @@ kms_composite_mixer_handle_port (KmsBaseHub * mixer,
       gst_element_sync_state_with_parent (capsfilter);
       gst_element_sync_state_with_parent (self->priv->videotestsrc);
     }
+
     gst_element_sync_state_with_parent (self->priv->videomixer);
     gst_element_sync_state_with_parent (self->priv->mixer_video_agnostic);
 
@@ -770,7 +775,7 @@ kms_composite_mixer_handle_port (KmsBaseHub * mixer,
 }
 
 static void
-kms_composite_mixer_dispose (GObject * object)
+kms_composite_mixer_dispose (GObject *object)
 {
   KmsCompositeMixer *self = KMS_COMPOSITE_MIXER (object);
 
@@ -783,7 +788,7 @@ kms_composite_mixer_dispose (GObject * object)
 }
 
 static void
-kms_composite_mixer_finalize (GObject * object)
+kms_composite_mixer_finalize (GObject *object)
 {
   KmsCompositeMixer *self = KMS_COMPOSITE_MIXER (object);
 
@@ -797,8 +802,55 @@ kms_composite_mixer_finalize (GObject * object)
   G_OBJECT_CLASS (kms_composite_mixer_parent_class)->finalize (object);
 }
 
+void
+kms_composite_mixer_set_property (GObject *object, guint property_id,
+    const GValue *value, GParamSpec *pspec)
+{
+  KmsCompositeMixer *compositeMixer = KMS_COMPOSITE_MIXER (object);
+
+  switch (property_id) {
+    case PROP_WIDTH:{
+      compositeMixer->priv->output_width = g_value_get_int (value);
+      break;
+    }
+    case PROP_HEIGHT:
+      compositeMixer->priv->output_height = g_value_get_int (value);
+      break;
+    case PROP_FRAMERATE:
+      compositeMixer->priv->output_framerate = g_value_get_int (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+      break;
+  }
+}
+
+void
+kms_composite_mixer_get_property (GObject *object, guint property_id,
+    GValue *value, GParamSpec *pspec)
+{
+  KmsCompositeMixer *compositeMixer = KMS_COMPOSITE_MIXER (object);
+
+  switch (property_id) {
+    case PROP_WIDTH:
+      g_value_set_int (value, compositeMixer->priv->output_width);
+      break;
+    case PROP_HEIGHT:{
+      g_value_set_int (value, compositeMixer->priv->output_height);
+      break;
+    }
+    case PROP_FRAMERATE:{
+      g_value_set_int (value, compositeMixer->priv->output_framerate);
+      break;
+    }
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+      break;
+  }
+}
+
 static void
-kms_composite_mixer_class_init (KmsCompositeMixerClass * klass)
+kms_composite_mixer_class_init (KmsCompositeMixerClass *klass)
 {
   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
   KmsBaseHubClass *base_hub_class = KMS_BASE_HUB_CLASS (klass);
@@ -811,6 +863,21 @@ kms_composite_mixer_class_init (KmsCompositeMixerClass * klass)
   gobject_class->dispose = GST_DEBUG_FUNCPTR (kms_composite_mixer_dispose);
   gobject_class->finalize = GST_DEBUG_FUNCPTR (kms_composite_mixer_finalize);
 
+  gobject_class->set_property = kms_composite_mixer_set_property;
+  gobject_class->get_property = kms_composite_mixer_get_property;
+
+  g_object_class_install_property (gobject_class, PROP_WIDTH,
+      g_param_spec_int ("width", "width",
+          "Width of the screen",
+          0, G_MAXINT, 0, G_PARAM_READWRITE | GST_PARAM_MUTABLE_READY));
+  g_object_class_install_property (gobject_class, PROP_HEIGHT,
+      g_param_spec_int ("height", "height",
+          "Height of the screen",
+          0, G_MAXINT, 0, G_PARAM_READWRITE | GST_PARAM_MUTABLE_READY));
+  g_object_class_install_property (gobject_class, PROP_FRAMERATE,
+      g_param_spec_int ("framerate", "framerate",
+          "Framerate of the screen",
+          0, G_MAXINT, 0, G_PARAM_READWRITE | GST_PARAM_MUTABLE_READY));
   base_hub_class->handle_port =
       GST_DEBUG_FUNCPTR (kms_composite_mixer_handle_port);
   base_hub_class->unhandle_port =
@@ -830,7 +897,7 @@ kms_composite_mixer_class_init (KmsCompositeMixerClass * klass)
 }
 
 static void
-kms_composite_mixer_init (KmsCompositeMixer * self)
+kms_composite_mixer_init (KmsCompositeMixer *self)
 {
   self->priv = KMS_COMPOSITE_MIXER_GET_PRIVATE (self);
 
@@ -841,13 +908,14 @@ kms_composite_mixer_init (KmsCompositeMixer * self)
   //TODO:Obtain the dimensions of the bigger input stream
   self->priv->output_height = 600;
   self->priv->output_width = 800;
+  self->priv->output_framerate = 15;
   self->priv->n_elems = 0;
 
   self->priv->loop = kms_loop_new ();
 }
 
 gboolean
-kms_composite_mixer_plugin_init (GstPlugin * plugin)
+kms_composite_mixer_plugin_init (GstPlugin *plugin)
 {
   return gst_element_register (plugin, PLUGIN_NAME, GST_RANK_NONE,
       KMS_TYPE_COMPOSITE_MIXER);

server/module-elements/src/gst-plugins/kmscompositemixer.h

@@ -57,6 +57,15 @@ typedef struct _KmsCompositeMixer KmsCompositeMixer;
 typedef struct _KmsCompositeMixerClass KmsCompositeMixerClass;
 typedef struct _KmsCompositeMixerPrivate KmsCompositeMixerPrivate;
 
+enum
+{
+  PROP_ZERO,
+  PROP_WIDTH,
+  PROP_HEIGHT,
+  PROP_FRAMERATE,
+  N_PROPERTIES
+};
+
 struct _KmsCompositeMixer
 {
   KmsBaseHub parent;

server/module-elements/src/server/config/Composite.conf.ini

@@ -0,0 +1,4 @@
+width=10
+height=10
+framerate=10
+; Default resolution and framerate