Or, if
your objective is highest possible quality (perhaps for output display on a television), then choose the
maximum resolution supported for your aspect ratio.
Table 6-3: Popular Video Aspect Ratios
Aspect ratio Description
16:9 (1.78:1) Widescreen TV. Widescreen aspect ratio usually used by HDTV and widescreen
televisions.
4:3 (or 1.33:1) Standard TV. Traditional ???box??? aspect ratio standard for TV.
2:35:1 Cinemascope widescreen. A ???super widescreen??? aspect ratio used in Cinemascope
and Panavision motion pictures.
Chapter 6: Advanced Programming Topics: Canvas and Video
149
Some newer video tools and devices support anamorphic encoding . When a video is anamorphic encoded,
it does not have a single hardcoded aspect ratio. Instead, the output device processes the anamorphic
pixel aspect ratio (PAR) information stored in the video and displays it based on its native aspect ratio.
However, currently iPhone and iPod touch cannot handle PAR and will display any anamorphic videos
in a distorted manner. Therefore, avoid anamorphic encoded videos.
Exporting for Wi-Fi and EDGE
If users of your application will access the videos over both Wi-Fi and EDGE networks, you will want to
export two different versions of the video ??” one that is optimized for Wi-Fi and one optimized for
EDGE.
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