# bipack

Script for simulating traveling mattes with ffmpeg. Achieve the effect of bipacked film with high contrast masks with a simple bash script.

[Read more about traveling mattes.](https://en.wikipedia.org/wiki/Matte_(filmmaking)#Bi-pack_process)

## Requirements

Uses `ffmpeg` to generate matte layers, apply mattes as alpha masks and render the final video.

Installation instructions for ffmpeg here: https://github.com/adaptlearning/adapt_authoring/wiki/Installing-FFmpeg

## Usage

`sh bipack.sh A.mp4 B.mp4 matte.mp4 output.mov`

This command will take video `A.mp4` and `B.mp4` as image sources while using `matte.mp4` as a high contrast matte which seperates the two image sources.

![bipack examples](img/example.jpg?raw=true "Examples")

## Explaination

This script started as a multi-command experiment that finally got reduced to a single command that leans heavily on ffmpeg's `maskmerge` filter: [Documentation](https://ffmpeg.org/ffmpeg-filters.html#maskedmerge)

Uses 1280x720 resolution and Apple ProRes 422 HQ as the output format, right now but change that easily in the script. Check it out!