schema_version: 0.3
type: filter
identifier: mask_start
title: Setup a filter mask
version: 4
copyright: Meltytech, LLC
creator: Dan Dennedy
license: LGPLv2.1
language: en
tags:
  - Video
description: >
  This filter works in conjunction with the mask_apply filter to make filter
  masking easier. This filter makes a snapshop of the frame before applying
  a filter, typically one to affect the alpha channel defining the mask. Then,
  the mask_apply filter uses a transition to composite the current frame's
  image over the snapshot. The typical use case is to add filters in the
  following sequence: mask_start, zero or more filters, mask_apply.

parameters:
  - identifier: filter
    title: Filter
    description: The name of a filter
    type: string
    argument: yes
    default: frei0r.alphaspot
    mutable: yes

  - identifier: filter.*
    type: properties
    description: >
      Properties to set on the encapsulated filter