diff options
| author | Allan Sandfeld Jensen <allan.jensen@theqtcompany.com> | 2016-02-25 16:29:49 +0100 |
|---|---|---|
| committer | Allan Sandfeld Jensen <allan.jensen@theqtcompany.com> | 2016-04-12 12:52:34 +0000 |
| commit | cd06d901af2b7c707db430293ab6efae354f4742 (patch) | |
| tree | aee9da4229a64238a8846f0e21b05bce910007e0 /src/corelib/global | |
| parent | 1bd0ab7050304d9e8989cde77e486947c56b9696 (diff) | |
Implement ordered dithering for image format conversions
QImage::convertToFormat was ignoring its conversion flag argument, only
performing dithering when converting to indexed formats.
This patch updates the documentation and implements ordered dithering
for other conversions.
Change-Id: I807353d61669694185b7e595ef262d80d9fbb3f1
Reviewed-by: Gunnar Sletta <gunnar@sletta.org>
Diffstat (limited to 'src/corelib/global')
| -rw-r--r-- | src/corelib/global/qnamespace.qdoc | 22 |
1 files changed, 10 insertions, 12 deletions
diff --git a/src/corelib/global/qnamespace.qdoc b/src/corelib/global/qnamespace.qdoc index dfa7112043..03ebc1d106 100644 --- a/src/corelib/global/qnamespace.qdoc +++ b/src/corelib/global/qnamespace.qdoc @@ -737,27 +737,25 @@ \value MonoOnly The pixmap becomes monochrome. If necessary, it is dithered using the chosen dithering algorithm. - Dithering mode preference for RGB channels: + Dithering mode preference: - \value DiffuseDither (default) - A high-quality dither. - \value OrderedDither A faster, more ordered dither. + \value DiffuseDither (default) - A high-quality dither using error diffusion. + \value OrderedDither A faster, ordered dither. \value ThresholdDither No dithering; closest color is used. - Dithering mode preference for alpha channel: + Dithering mode preference for 1-bit alpha masks: \value ThresholdAlphaDither (default) - No dithering. - \value OrderedAlphaDither A faster, more ordered dither. - \value DiffuseAlphaDither A high-quality dither. + \value OrderedAlphaDither A faster, ordered dither. + \value DiffuseAlphaDither A high-quality dither using error diffusion. \omitvalue NoAlpha Color matching versus dithering preference: - \value PreferDither (default when converting to a pixmap) - Always dither - 32-bit images when the image is converted to 8 bits. - \value AvoidDither (default when converting for the purpose of saving to - file) - Dither 32-bit images only if the image has more than 256 - colors and it is being converted to 8 bits. - \omitvalue AutoDither + \value PreferDither Always dither images when converting to smaller color-spaces. + \value AvoidDither Only dither to indexed formats if the source image uses more + different colors than the size of the color table of the destination format. + \value AutoDither (default) - Only dither when down-converting to 1 or 8-bit indexed formats. \omitvalue ColorMode_Mask \omitvalue Dither_Mask |