KrashDev.com

The Software Engineering Portfolio for Nathan Karasch

Codable Media Mashup

A language. A command line tool. A quick and dirty video editor for the power user.

Overview

Codable Media Mashup (CoMM) is both a language and a command line tool used for slicing and splicing online videos together. The purpose is to allow people to quickly and efficiently make “highlights reel” or “compilation” types of movies using a collection of online videos. The traditional video editing process might look something like this:

  • Individually download the videos, and wait for them to complete.
  • Load them into a bulky video editing application, and wait for it to process each video for thumbnails.
  • Select clips from the various source videos, adjust the time sliders, wait for the CPU to catch up as the graphics card gets bogged down.
  • Waiting, waiting, waiting… you get the point.

By contrast, with a “codable” video editing experience, users can avoid the wait! Or at least most of it. For many people, video editing shouldn’t need a feature-heavy application. It just needs to put pieces of videos together. The less time spent doing it, the better! In addition to it being faster, all the downloading and processing is done in the same contiguous block of time. This allows the user to “set it and forget it” so they can work on something else until their video is complete.

Code Repository
github.com/KrashLeviathan/codable_media_mashup
Started
1 December 2017
Completed
11 December 2017

Potential use cases:

  • Game footage highlights from the season
  • Top ten funniest Seinfeld moments
  • Cat fail compilations
  • Caruso one-liners montage
  • Compilation of every time Neo says “No”, “Why”, or “I don’t understand”. Wake up Neo…

Project Complexity

This project involved creating a fully functioning interpreter that performs lexical analysis, grammar parsing, translation, and execution. Up until this point, we have only created lexers and parsers with ANTLR. The interpreter had to be able to provide helpful error messages and output useful log files as well, which involved understanding StandardError/StandardOutput redirection in a Java program running a bash script.

Creation, Analysis, and Evaluation

Creation began by defining what we wanted the language to do and writing the grammar from that definition. We focused on getting end-to-end integration and a working prototype before drilling down on the finer details of the program. Translation and execution were implemented by using a bash script as an intermediate language, and then running that script from within the Java application. The basic features of the program allow the user to define the output video file name and cache, download numerous videos, slice them into shorter clips, and then join those clips into a single video.

Once the initial prototype was functional, it was analyzed and improved upon in additional iterations. The repository was completely restructured and refactored to comply to better coding standards and to promote readability and maintainability. The process involved decoupling distinct modules, restructuring the file directory, updating build scripts, removing cruft, refactoring variables and functions, and adding comments and documentation.

The application and project goals were evaluated intermittently during development, and plans had to be adjusted to arrive at a satisfactory end result within the allotted time. We determined that it was more important to produce a stable application with a few core features and robust error handling than it was to make a buggy, unstable application with lots of features. Original plans for a client-server web application were shifted to target a command line application, and extra features were tabled to focus on the more essential pieces of functionality.

The result, Codable Media Mashup, is a fun new way to edit videos with a few easy commands!