filters.xml

<?xml version="1.0" encoding="utf-8"?>
<form>
    <config>
        <inlinehelp button="show"/>
    </config>
    <field name="directory"
           label="PLG_SYSTEM_CGWEBP_DIRECTORY" description="PLG_SYSTEM_CGWEBP_DIRECTORY_DESC"
           type="text" required="required" />
    <field name="extensions" label="PLG_SYSTEM_CGWEBP_EXTENSIONS" type="checkboxes" required="required">
        <option value="jpg|jpeg|JPG|JPEG">JPG/JPEG</option>
        <option value="png|PNG">PNG</option>
    </field>
    <field name="quality" type="cgrange" 
           label="PLG_SYSTEM_CGWEBP_QUALITY" description="PLG_SYSTEM_CGWEBP_QUALITY_DESC" 
           first="1" last="100" default="60" step="1" required="required" />
    <field name="stored_time" type="hidden" label="PLG_SYSTEM_CGWEBP_STORED_TIME"
           description="PLG_SYSTEM_CGWEBP_STORED_TIME_DESC" />
    <field name="excluded" type="textarea" default="" label="PLG_SYSTEM_CGWEBP_EXCLUDES"
           description="PLG_SYSTEM_CGWEBP_EXCLUDES_DESC" rows="3" cols="20" filter="raw"/>
</form>