SheerVideo User Manual
Apple QuickTime Player
SheerVideo's breakthrough speed and power make it possible to stream standard-definition video
to or from an ordinary (in other words, slow) hard disk in real time on an ordinary personal computer.
SheerVideo also makes it possible to stream the highest-definition HD video over a Firewire 800 bus.
Here we offer some tips for achieving these feats and for maximizing your enjoyment of SheerVideo's performance with QuickTime Player,
especially for situations, such as capture and playback, where real-time performance is critical.
First, some general speed tips. Make sure that:
- your disk has enough unfragmented free space that your entire video can be stored in a single contiguous region of the disk.
- your video application isn't competing for processing time with other, unnecessary processes, especially processes such as web browsers that keep the computer busy while they're idling in the background.
- your video is in a "flattened", self-contained movie without any edits that would force the disk head to thrash around.
- your video content is clean, with an absolute minimum of uncompressible noise such as dithering, fixed pattern noise, filter noise, tape noise, film grain noise, transmission noise, etc.
In addition, note that the current release of SheerVideo does perfect-fidelity encoding and decoding only,
and does not support any operation that would cause loss of image information other than pixel-format conversion.
Thus SheerVideo does NOT do:
- scaling, shearing, or other geometric transformations
Therefore, for optimal speed performance, you should view SheerVideo QuickTime movies:
- with your Displays Control Panel set to Millions of Colors
- with the window set to View > Actual Size (full resolution)
with the transformation set to the identity transformation by
Window > Show Movie Properties: Video Track: Size: Reset
- with the entire window visible on a single screen
- with no other windows covering any of the SheerVideo window
- with a null mask: Window > Show Movie Properties: Video Track: Mask: Clear
- with the transparency set to Window > Show Movie Properties: Video Track: Transparency: None or Dither Copy
Note: SheerVideo is not yet optimized for MMX on the PC.
Also, most encoding and decoding paths involving conversion between color spaces, chroma subsampling rates, or precision
are not yet optimized for the G4 or G5.