geometrictransform: add headers with example launch lines

Add description headers for all geometrictransform elements so we can have
gst-launch-1.0 example launch lines for all of them.

gst/geometrictransform/gstbulge.c

@@ -41,6 +41,21 @@
  * Boston, MA 02110-1301, USA.
  */
 
+/**
+ * SECTION:element-bulge
+ * @see_also: geometrictransform
+ *
+ * Bugle is a geometric image transform element. It adds a protuberance in the
+ * center point.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! bulge ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
+
 #ifdef HAVE_CONFIG_H
 #  include <config.h>
 #endif

gst/geometrictransform/gstcircle.c

@@ -47,6 +47,20 @@
  * his code.
  */
 
+/**
+ * SECTION:element-circle
+ * @see_also: geometrictransform
+ *
+ * Circle is a geometric image transform element. It warps the picture into an
+ * arc shaped form.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! circle ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>

gst/geometrictransform/gstdiffuse.c

@@ -47,6 +47,20 @@
  * his code.
  */
 
+/**
+ * SECTION:element-diffuse
+ * @see_also: geometrictransform
+ *
+ * Diffuse is a geometric image transform element. It diffuses the image by
+ * moving its pixels in random directions.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! diffuse ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>

gst/geometrictransform/gstfisheye.c

@@ -41,6 +41,21 @@
  * Boston, MA 02110-1301, USA.
  */
 
+/**
+ * SECTION:element-fisheye
+ * @see_also: geometrictransform
+ *
+ * Fisheye is a geometric image transform element. It simulates a fisheye lens
+ * by zooming on the center of the image and compressing the edges.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! fisheye ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
+
 #ifdef HAVE_CONFIG_H
 #  include <config.h>
 #endif

gst/geometrictransform/gstkaleidoscope.c

@@ -47,6 +47,20 @@
  * his code.
  */
 
+/**
+ * SECTION:element-kaleidoscope
+ * @see_also: geometrictransform
+ *
+ * The kaleidscope element applies 'kaleidoscope' geometric transform to the
+ * image.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! kaleidoscope ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>

gst/geometrictransform/gstmarble.c

@@ -47,6 +47,20 @@
  * his code.
  */
 
+/**
+ * SECTION:element-marble
+ * @see_also: geometrictransform
+ *
+ * Marble is a geometric image transform element. It applies a marbling effect
+ * to the image.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! marble ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>

gst/geometrictransform/gstmirror.c

@@ -41,6 +41,21 @@
  * Boston, MA 02110-1301, USA.
  */
 
+/**
+ * SECTION:element-mirror
+ * @see_also: geometrictransform
+ *
+ * Mirror is a geometric transform element. It splits the image into two halves
+ * and reflects one over each other.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! mirror ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
+
 #ifdef HAVE_CONFIG_H
 #  include <config.h>
 #endif

gst/geometrictransform/gstperspective.c

@@ -47,6 +47,20 @@
  * http://docs.oracle.com/cd/E17802_01/products/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/PerspectiveTransform.html
  */
 
+/**
+ * SECTION:element-perspective
+ * @see_also: geometrictransform
+ *
+ * The perspective element applies a 2D perspective transform.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! perspective ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
+
 /* FIXME: suppress warnings for deprecated API such as GValueArray
  * with newer GLib versions (>= 2.31.0)
  *

gst/geometrictransform/gstpinch.c

@@ -47,6 +47,19 @@
  * his code.
  */
 
+/**
+ * SECTION:element-pinch
+ * @see_also: geometrictransform
+ *
+ * Pinch applies a 'pinch' geometric transform to the image.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! pinch ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>

gst/geometrictransform/gstrotate.c

@@ -47,6 +47,19 @@
  * his code.
  */
 
+/**
+ * SECTION:element-rotate
+ * @see_also: geometrictransform
+ *
+ * The rotate element transforms the image by rotating it by a specified angle.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! rotate angle=0.78 ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>

gst/geometrictransform/gstsphere.c

@@ -47,6 +47,19 @@
  * his code.
  */
 
+/**
+ * SECTION:element-sphere
+ * @see_also: geometrictransform
+ *
+ * The sphere element applies a 'sphere' geometric transform to the image.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! sphere ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>

gst/geometrictransform/gstsquare.c

@@ -41,6 +41,20 @@
  * Boston, MA 02110-1301, USA.
  */
 
+/**
+ * SECTION:element-square
+ * @see_also: geometrictransform
+ *
+ * The square element distorts the center part of the image into a square.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! square zoom=100 ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
+
 #ifdef HAVE_CONFIG_H
 #  include <config.h>
 #endif

gst/geometrictransform/gststretch.c

@@ -41,6 +41,20 @@
  * Boston, MA 02110-1301, USA.
  */
 
+/**
+ * SECTION:element-stretch
+ * @see_also: geometrictransform
+ *
+ * The stretch element stretches the image in a circle around the center point.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! stretch ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
+
 #ifdef HAVE_CONFIG_H
 #  include <config.h>
 #endif

gst/geometrictransform/gsttunnel.c

@@ -41,6 +41,21 @@
  * Boston, MA 02110-1301, USA.
  */
 
+/**
+ * SECTION:element-tunnel
+ * @see_also: geometrictransform
+ *
+ * Tunnel is a geometric image transform element. It applies a light tunnel
+ * effect.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! tunnel ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
+
 #ifdef HAVE_CONFIG_H
 #  include <config.h>
 #endif

gst/geometrictransform/gsttwirl.c

@@ -47,6 +47,19 @@
  * his code.
  */
 
+/**
+ * SECTION:element-twirl
+ * @see_also: geometrictransform
+ *
+ * The twirl element twists the image from the center out.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! twirl ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>

gst/geometrictransform/gstwaterripple.c

@@ -47,6 +47,19 @@
  * his code.
  */
 
+/**
+ * SECTION:element-waterripple
+ * @see_also: geometrictransform
+ *
+ * The waterripple element creates a water ripple effect on the image.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch-1.0 -v videotestsrc ! waterripple ! videoconvert ! autovideosink
+ * ]|
+ * </refsect2>
+ */
 
 #ifdef HAVE_CONFIG_H
 #  include <config.h>