Work

Digital Subtitling - An Industry Need

During the development of MATRIX, a few of CHROME Imaging's beta testers and clients told us that one of the biggest bottlenecks in their film deliveries was the subtitling phase. Until now, most, if not all, subtitling is done through an archaic system of loading text files into a special optical film printer, printing a transparent subtitle reel and then optically transferring it to a copy of the underlying film. This process is time-consuming and expensive because of the specialized materials required, the cost of development chemicals, and the little room for error. A digital subtitling system, on the other hand, is much more flexible and gives a greater degree of freedom for the choice of font, colors, etc. Digital subtitling solutions that exist today are mainly geared towards the broadcast market and do not support the special color characteristics or the resolution that the film industry works with. Users often resort to using tools that are not meant for subtitling in order to get their job done.

Designing Subtitles

The first step in designing a robust and "production-proof" subtitling tool for film was to collect a list of user requirements and problems with existing workflows. Among others, these were:

High cost of optical subtitling equipment.
Long work process
Little or no choice of color, size and font of on-screen text.
Crude rendering of subtitles (in the case of laser processing)
No way to efficiently separate subtitles from similar-color backgrounds (e.g. white titles on white backround)
Little or no integration with digital acquisition systems.
No room for error

parameters

Next, I listed all the possible parameters and settings that would be required for subtitles. These were then categorized (see image above) in order to get a clear picture of how the UI and subtitle file format will be structured. Following a content/presentation paradigm, all subtitle information was eventually divided into two main parts:

Subtitle text and timing information
Subtitle display and style.

These are directly reflected in the UI as two panels of options - one containing an editable table of subtitle text and timing information (Subtitles) as well as another panel strictly containing display information (Display). This system ensures that all subtitle diplay properties such as font size, color, etc. will remain constant throughout. The only editable settings per subtitle are its position in the image and its style (e.g. using italics for a subtitle during voice-overs).

User-defined title margins
Access to all system fonts and styles
Character and line spacing adjustment
Automatic calculation of font size depending on image resolution
Customizable outline, shadow and background box effects to separate text from background
Global antialiasing option

The MATRIX Subtitle File Generator

One main issue that was not accounted for during the design process was the fact that typing possible thousands of subtitles is a very time-consuming process. Users would type subtitles directly in the MATRIX software, rendering the system useless to others and "hogging" valuable production time. This sparked off the development of the MATRIX Subtitle File Generator, a web-based application that enables users to input formatted subtitle information and convert it to an XML-based that can be loaded into MATRIX. With this tool, facilities could create subtitle files on a laptop or small computer and eventually load the resulting XML file into MATRIX.

This seemingly simple PHP app lets users enter lines of subtitle text, start time and end time information. All lines of subtitle info are then processed for information and populate a downloadable XML. This application features rigorous syntax error checking, making sure that all information is correctly formatted. Additionally all time values are checked for correct formatting and validity against a preset film speed.

Try it! (login required)

Real-world Application

Since the MATRIX subtitling tool was introduced, post facilities have the ability to deliver subtitling projects in a fraction of the time it would take with traditional methods. Over a dozen trailers and films have been subtitled, with visible differences in text quality and readablility.