Motion tracker: add steps parameter. Patch by Balazs Durakovacs

Differential Revision: https://phabricator.kde.org/D21375

data/effects/tracker.xml

 <!DOCTYPE kpartgui>
 <effect tag="opencv.tracker" id="opencv.tracker" condition="results" sync_in_out="1">
-	<name>Motion Tracker</name>
-	<description>Select a zone to follow its movements</description>
-	<author>Jean-Baptiste Mardelle</author>
-	<parameter type="geometry" name="rect" default="50%,50%:25%x25%" fixed="1" opacity="false" conditional="1">
-		<name>Rectangle</name>
-	</parameter>
-        <parameter type="list" name="algo" default="KCF" paramlist="KCF;MIL;BOOSTING;TLD" conditional="1">
-	   <paramlistdisplay>KCF,MIL,Boosting,TLD</paramlistdisplay>
-		<name>Tracker algorithm</name>
-	</parameter>
-        <parameter type="list" name="shape" default="0" paramlist="0;1;2">
-	   <paramlistdisplay>Rectangle,Ellipse,Arrow</paramlistdisplay>
-		<name>Frame shape</name>
-	</parameter>
-	<parameter type="constant" name="shape_width" max="100" min="-1" default="1" suffix="pixels">
-		<name>Shape width</name>
-	</parameter>
-	<parameter type="color" name="shape_color" default="0xff0000ff">
-		<name>Shape color</name>
-	</parameter>
-        <parameter type="constant" name="blur" max="200" min="0" default="0">
-		<name>Blur</name>
-	</parameter>
-        <parameter type="list" name="blur_type" default="0" paramlist="0;1">
-	   <paramlistdisplay>Median Blur,Gaussian Blur</paramlistdisplay>
-		<name>Blur type</name>
-	</parameter>
-        <parameter type="readonly" name="results" value="">
-            <name>Tracking data</name>
-            <comment>Click to copy to clipboard</comment>
-	</parameter>
+    <name>Motion Tracker</name>
+    <description>Select a zone to follow its movements</description>
+    <author>Jean-Baptiste Mardelle</author>
+    <parameter type="geometry" name="rect" default="50%,50%:25%x25%" fixed="1" opacity="false" conditional="1">
+        <name>Rectangle</name>
+    </parameter>
+    <parameter type="list" name="algo" default="KCF" paramlist="KCF;MIL;BOOSTING;TLD" conditional="1">
+        <paramlistdisplay>KCF,MIL,Boosting,TLD</paramlistdisplay>
+        <name>Tracker algorithm</name>
+    </parameter>
+    <parameter type="constant" name="steps" default="5" min="0" max="120">
+        <name>Keyframes spacing</name>
+        <comment>Defines the frequency of stored keyframes. A keyframe is created every steps frames.</comment>
+    </parameter>
+    <parameter type="list" name="shape" default="0" paramlist="0;1;2">
+        <paramlistdisplay>Rectangle,Ellipse,Arrow</paramlistdisplay>
+        <name>Frame shape</name>
+    </parameter>
+    <parameter type="constant" name="shape_width" max="100" min="-1" default="1" suffix="pixels">
+        <name>Shape width</name>
+    </parameter>
+    <parameter type="color" name="shape_color" default="0xff0000ff">
+        <name>Shape color</name>
+    </parameter>
+    <parameter type="constant" name="blur" max="200" min="0" default="0">
+        <name>Blur</name>
+    </parameter>
+    <parameter type="list" name="blur_type" default="0" paramlist="0;1">
+        <paramlistdisplay>Median Blur,Gaussian Blur</paramlistdisplay>
+        <name>Blur type</name>
+    </parameter>
+    <parameter type="readonly" name="results" value="">
+        <name>Tracking data</name>
+        <comment>Click to copy to clipboard</comment>
+    </parameter>
     <parameter type="filterjob" filtertag="opencv.tracker" consumer="null" consumerparams=" all=1 terminate_on_pause=1">
         <name conditional="Reset">Analyse</name>
         <jobparam name="conditionalinfo">Filter is in preview mode. Click Analyse to see real effect</jobparam>
-		<jobparam name="key">results</jobparam>
-		<jobparam name="finalfilter">opencv.tracker</jobparam>
+        <jobparam name="key">results</jobparam>
+        <jobparam name="finalfilter">opencv.tracker</jobparam>
         <jobparam name="displaydataname">Motion tracking</jobparam>
-	</parameter>
+    </parameter>
 </effect>