Re: Colorchange during jpg->webp conversion
Bob Friesenhahn <[email protected]>
| Newsgroups | gmane.comp.video.graphicsmagick.help |
|---|---|
| Message-ID | <[email protected]> |
On Thu, 11 May 2017, Przemysław Sobala wrote: > Hi > I'm using GraphicsMagick 1.3.25 and libwebp 0.5.2 and I've noticed color > change when converting images from JPG to WEBP, eg.: > > gm convert http://d.wpimg.pl/1972545173--1156527689/paulina-sykut.jpg > gm.webp > > Please compare skin color in source jpg and target webp > (http://pasteboard.co/50Q0V8llI.png). > FFmpeg that uses the same libwebp doesn't make such noticeable color change. I think that GraphicsMagick and WebP are correctly saving the pixel values (looks good on an uncorrected display). It seems that you discovered that the ICC profile is necessary in order to display the image correctly. I think that there is a pull request for code to save/retrieve ICC profiles for WebP. WebP is primarly intended for small images such as would be displayed in a web browser and it intends to optimize file size as much as possible. Given this, adding ICC profiles could significanly bloat the saved file. Some ICC profiles are over 1MB in size (many ICC profiles are rather small as yours is only 560 bytes). If one is preparing images for web, then it is best to apply the ICC profile and convert the image to sRGB space. Bob -- Bob Friesenhahn [email protected], http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Graphicsmagick-help mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/graphicsmagick-help