On Tuesday 17 July 2012 Jul, you wrote: > What we presently have in a local branch is: > > 1) Grabbing embedded color profiles from PNG and JPEG images (eventually > support for more formats will come)
That would be excellent. > 2) Non-Automatic conversion of color profiles at load. This is done through > the constructor, where when loading an image you specify weather you preserve > the color profile or you convert to Screen. The default behavior keeps the > loaded image unchanged. Hm... I would prefer to be able to specify a working space here -- not just the screen target. That makes it possible to use a linear rgb profile to convert to real linear rgb and actually be able to do stuff with the pixels. > > What we don't have: > 1) Exporting images with embedded color profiles > 2) Modifying a color profile (access only to high level data such as > description and colorspace) > > The API looks as follows: > > enum QColorSpace {RGB, CMYK, Invalid} > > QColorProfile > ------------- > QString description() > QColorSpace colorspace() For my applications, I would also want to be able to get the original profile data out of QColorProfile, btw. Especially when using the QScreen api. > QImage > ------------- > QColorProfile colorProfile() > void setColorProfile(colorProfile) > void convertToColorProfile(colorProfile) > > QScreen > ------------- > QColorProfile colorProfile() > > Windows and Mac OS X have built in support for color profile conversion. For > linux X11 supports color profiles after loading several modules, otherwise > uses sRGB. This is where the Oyranos project comes in. On X11, you can use the X11 atom to check what the user has set -- that works for both oyranos and colord managed desktops. > All the color profile conversion takes place using the littleCMS library > which seems to be sort of standard for that job. Oyranos is also using it. yes, lcms2 is pretty much the standard. And it's small and excellent. > > ________________________________________ > From: development-bounces+alexandros.dermenakis=nokia....@qt-project.org > [development-bounces+alexandros.dermenakis=nokia....@qt-project.org] on > behalf of ext Boudewijn Rempt [b...@valdyas.org] > Sent: Monday, July 16, 2012 9:15 PM > To: development@qt-project.org > Subject: Re: [Development] Color Profile support on Qt > > On Monday 16 July 2012 Jul, Olivier Goffart wrote: > > All QPainter operations (at least in the raster engine) assume a linear > > color > > space. That means that the color conversion need to hapen last, right before > > being shown to the screen. After all kind of blending operations or anything > > done with QPainter. (That means it could even been done in the platform > > plugin) > > Are you really sure about that? It's extremely unlikely that one encounters a > linear light rgb png file in the wild, for instance, most assume sRGB. > Unmanaged RGB isn't automatically linear, either -- it most likely is just a > mess. > > -- > Boudewijn Rempt > http://www.valdyas.org, http://www.krita.org, http://www.boudewijnrempt.nl > _______________________________________________ > Development mailing list > Development@qt-project.org > http://lists.qt-project.org/mailman/listinfo/development > -- Boudewijn Rempt http://www.valdyas.org, http://www.krita.org, http://www.boudewijnrempt.nl _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development