edl_composer

Edl Composer

The EDL composer node module can be used to create Edit Decision List. EDL, Edit Decision List, is a plain text format that describes a video sequence. It can be opened in a video editing software to reconnect media to assemble a video sequence. Originally extracted from autoEdit.io

Setup

Setup for Contributing

Clone the repo

git clone [e-mail]:pietrop/edl_composer.git

Install dependencies

npm install

And if you want to try it out

node example-usage.js

Setup for usage

To use in your project, the module can be found on npm as edl_composer so just run the following to add to your project.

npm install edl_composer

Usage

The EDL sequence should have the following attributes

var edlSq = {
    "title": "Demo Title of project",
    "events":  [
      { "id":1,
        "startTime": 10, // in seconds 
        "endTime": 20,
        "reelName":"SomeReelName",
        "clipName":"Something.mov",
        "offset": "00:00:28:08", //offset is optional default is "00:00:00:00"
        "fps": 25
      },
      { "id":2,
        "startTime": 45,
        "endTime": 55,
        "reelName":"SomeOtherReelName",
        "clipName":"SomethingElse.mov",
        "offset": "00:00:28:08",
        "fps": 29.97
      },
        { "id":2,
        "startTime": 45,
        "endTime": 55,
        "reelName":"NA",
        "clipName":"SomethingElse.mov",
        "offset": "00:00:28:08",
        "fps": 24
      }
    ]
}

And it can be parsed and composed into an EDL as following.

 
var edl = new EDL(edlSq);
console.log(edl.compose());

This returns a string that you can write to file or else.

TITLE: Demo Title of project
FCM: NON-DROP FRAME

001   SOMEREE  AA/V  C  00:00:00:00 00:00:00:00 00:00:00:00 00:00:10:00
* FROM CLIP NAME: Something.mov
FINAL CUT PRO REEL: SomeReelName REPLACED BY: SOMEREE

002   SOMEOTH  AA/V  C  00:00:00:00 00:00:00:00 00:00:10:00 00:00:20:00
* FROM CLIP NAME: SomethingElse.mov
FINAL CUT PRO REEL: SomeOtherReelName REPLACED BY: SOMEOTH

002    AX  AA/V  C  00:00:00:00 00:00:00:00 00:00:20:00 00:00:30:00
* FROM CLIP NAME: SomethingElse.mov

System Architecture

High level overview of system architecture

Understanding the EDL specs

Example EDL. For more on how to read an edl and understand the specs check this out.

TITLE: TEST PAPEREDIT
FCM: NON-DROP FRAME

001  Card01Ky AA/V  C        00:02:26:21 00:02:30:12 00:00:00:00 00:00:03:16
* FROM CLIP NAME:  KYLE_INTERVIEW.MOV
* COMMENT:
FINAL CUT PRO REEL: Card01_Kyle_Interview REPLACED BY: Card01Ky

002  Card01Ky AA/V  C        00:02:30:12 00:02:34:13 00:00:03:16 00:00:07:17
* FROM CLIP NAME:  KYLE_INTERVIEW.MOV
* COMMENT:
FINAL CUT PRO REEL: Card01_Kyle_Interview REPLACED BY: Card01Ky

003  Card02Je AA/V  C        00:00:26:12 00:00:27:00 00:00:07:17 00:00:08:05
* FROM CLIP NAME:  JEFF_INTERVIEW.MOV
* COMMENT:
FINAL CUT PRO REEL: Card02_Jeff_Interview REPLACED BY: Card02Je

004  Card02Je AA/V  C        00:00:28:22 00:00:32:00 00:00:08:05 00:00:11:08
* FROM CLIP NAME:  JEFF_INTERVIEW.MOV
* COMMENT:
FINAL CUT PRO REEL: Card02_Jeff_Interview REPLACED BY: Card02Je

005  Card01Ky AA/V  C        00:01:08:03 00:01:12:19 00:00:11:08 00:00:15:24
* FROM CLIP NAME:  KYLE_INTERVIEW.MOV
* COMMENT:
FINAL CUT PRO REEL: Card01_Kyle_Interview REPLACED BY: Card01Ky

Most important par is that

001  Card01Ky AA/V  C        00:02:26:21 00:02:30:12 00:00:00:00 00:00:03:16

I refer to the first part as edl head, which contains the title of the project

TITLE: {{projectTitle}}
FCM: NON-DROP FRAME

This is a edl line event, and group of lines I refer to it as the the edl body.

001  Card01Ky AA/V  C        00:02:26:21 00:02:30:12 00:00:00:00 00:00:03:16
* FROM CLIP NAME:  KYLE_INTERVIEW.MOV
* COMMENT:
FINAL CUT PRO REEL: Card01_Kyle_Interview REPLACED BY: Card01Ky

it might help to consider what are the variables we need to interpolate

{{line event number}}  {{reel name 7 digit abbreviation}} AA/V  C   {{clip in}} {{clip out}} {{tape/timeline in}} {{tape/timeline out}}
* FROM CLIP NAME:  {{clip name}}
* COMMENT:
FINAL CUT PRO REEL: {{reel full name}} REPLACED BY: {reel name 7 digit abbreviation}}

We could do more such as change the type of track AA/V and the type of cut C but since we are doing relativly simple edits we are not interested in this for now.

However let's consider the first line of the EDL event line in more details, because the timecodes part is where it can get confusing to understand what does what. It might be useful to understand a tiny bit of EDL history:

In the days of linear tape editing, EDLs were used to save and restore the timecode information for each edit performed on a computer-controlled editing system. Because timecode editing systems were expensive, many editors would perform offline edits with window dubs (low-quality copies of original footage with timecode visually superimposed, or burned, directly onto the image) and then create an EDL by hand for delivery to a computer-controlled editing system for the online edit.

• 001 line number
• Card01KyReel name (comes from camcorder metadata, usually name of the camcorder card). For files that don't have have (eg downloaded from youtube), needs to be set as AX.
• AA/V type of line event. audio and video in this case
• C type of edit, cut in this case, but could also be dissolve, however that would require two tracks in the same line
• clip in poin 00:02:26:21
• clip out point 00:02:30:12
• tape/timeline in point, starts with zero 00:00:00:00 on first line event, then is the timeline out point of the previous line event
• tape/timeline out point is duration of the clip(clip out point - clip in point) + tape/timeline in point of this line event. 00:00:03:16

What this means is that you have timecodes relative to the clip of the edl event line, in and out point, and then you have timecodes relative to the timeline of the sequence the edl is describing(that back in the day used to be referred to as tape).

Development env

How to run the development environment Coding style convention ref optional, eg which linter to use Linting, github pre-push hook - optional

• node
• npm

Build

How to run build

No build step

Tests

How to carry out tests

Minimal test using jest

npm test

Deployment

How to deploy the code/app into test/staging/production

No deployment just a node module