Interactive Rich Media

Subtitles are textual versions of the dialog in films and television programs, usually displayed at the bottom of the screen. They can either be a form of written translation of a dialog in a foreign language, or a written rendering of the dialog in the same language, with or without added information to help viewers to follow the dialog.

There exist a great number of subtitle formats and programs to create subtitles. An efficient and convenient subtitle editing tool that supports all the subtitle formats you need and has all the features you would want from such a tool is Subtitle Workshop 4 (beta 4) from URUWorks. It even includes spell check function and an advanced video preview feature.

DVD authoring is the process of creating a DVD video that can be played on a DVD player. DVD authoring software must conform to the specifications set by the DVD Forum group in 1995. The specifications are complicated due to the number of companies that were involved in creating them.

There are a lot of DVD authoring, encoding and burning programs available: professional, commercial, proprietary, free of charge and open source software. Among the free programs, I prefer  DVD Flick (only for Windows available), developped by Dennis Meuwissen (pseudo : Exl).

The size of a video image is measured in pixels for digital video, or horizontal scan lines and vertical lines of resolution for analog video. In the digital domain standard-definition television resolution is specified as 720/704/640 ×480 for NTSC and 768/720 × 576 for PAL or SECAM. However in the analog domain, the number of visible scanlines remains constant (486 NTSC/576 PAL) while the horizontal measurement varies with the quality of the signal: approximately 320 pixels per scanline for VCR quality, 400 pixels for TV broadcasts, and 720 pixels for DVD sources. Aspect ratio is preserved because of non-square “pixels”.
New high-definition televisions are capable of resolutions up to 1920 ×1080 )pixels per scan line by 1080 scan lines).
Aspect ratio describes the dimensions of video screens and video picture elements. All popular video formats are rectilinear, and are described by a ratio between width and height. The screen aspect ratio of a traditional television screen is 4:3. High definition televisions use an aspect ratio of 16:9.

Some common used video resolutions and aspect ratios are :

• 128 : 96 > 4 : 3
• 176 : 144 > 11 : 9
• 240 : 176 > 4 : 3
• 320 : 240 > 4 : 3
• 352 : 288 > 11 : 9
• 480 : 270 > 16 : 9
• 640 : 480 > 4 : 3
• 720 : 480 > 3 : 2

To keep the aspect ratio of a video without distortion when changing the resolution, you often need to crop or to padd the video (delete or add pixels on top, bottom, left and right side). I use the great video-tool Super from eRightSoft to do this job.