SheerVideo User Manual
QuickTime SettingsHigh-Quality Mode
SheerVideo Perfect-Fidelity Playback: The Sheer codecs are designed to be strictly nondestructive, and try to prevent QuickTime or the application from inadvertently losing image information by accidentally choosing the wrong destination pixel format for the codec, and thus reducing the sample precision, changing the chroma sampling, or converting the color space without increasing the sample precision.
However, SheerVideo does permit destructive pixel-format conversion for cases when the user needs this capability. This capability is controlled internally by QuickTime's codec accuracy parameter, whose value can be stored in the QuickTime movie file, and in application user interfaces is typically represented by a High Quality Mode checkbox or Quality pop-up menu. Most applications default to medium-quality or low-quality playback, because this usually results in greater speed.
To ensure that an open SheerVideo QuickTime movie, slide show, or image sequence is decoded to a compatible pixel format for perfect-fidelity playback, the playback accuracy needs to be set to "normal quality" or "high quality".
To permit high-precision Sheer movies to be played back on low-precision platforms, set the playback accuracy to "medium quality" or "low quality".