Slowmotion Converter

Description

This project provides a watcher that watch a given folder and generate a slowmotion copy of any video appearing in it with a name matching a given pattern.

I developed this script to be able to have slow motion replays during sport streaming I'm used to broadcast in my roller derby league Roller Derby Toulouse.

How it works?

I use OBS and this software provides a functionality that allows you to capture the last few seconds stored in a buffer by hitting a hotkey (see documentation).

It saves a video file in a specific folder according to your setup.

Slowmotion Converter watch this folder and generate a copy of the freshly created replay with a different frame rate.

In OBS, I add a scene with a VLC source in which I put slow motion replay created like that.

How to use it?

Prerequisites

Docker method

First build the image:

$ docker build -t local/slowmotion-converter .

Then you can either run the container using cli commands or a docker-compose file.

Personnaly I prefer the docker-compose method.

Create your docker-compose.yml in the root folder of this project:

version: '3.0'

services:
  slowmotion-converter:
    container_name: slowmotion-converter
    image: local/slowmotion-converter
    tty: true
    restart: always
    volumes:
      - ./:/var/www
      - /PATH/TO/REPLAYS/LOCAL/FOLDER/:/var/www/vids/
      - /PATH/WHERE/YOU/WANT/SLOMO/FILES/:/var/www/rendered/

Then simply run it:

$ docker-compose up

Your converter is now running and watching to a folder you mounted as a volume.

Each time a replay will be saved in /PATH/TO/REPLAYS/LOCAL/FOLDER/ on you local machine, a slow motion version will be copied into /PATH/WHERE/YOU/WANT/SLOMO/FILES/.

You now only have to set up a VLC source in your replays scene in OBS.

ATTENTION: for this to work, your replay files name have to be prefixed by the token: replay_. Ex.: replay_20181215-130627.mp4

Non virtual method

!! This method has not been tested

Pre-requisites:

• nodeJS 11
• ffmpeg

Steps:

• Set up OBS to write replays into /PATH/TO/slowmotion-converter/vids/
• Run the watcher from its root folder: node index.js