ICC Examin 1.0 on Android

ICC Examin allows since version 1.0 ICC Color Profile viewing on the Android mobile platform. ICC Examin shows ICC color profile elements graphically. This way it is much easier to understand the content. Color primaries, white point, curves, tables and color lists are displayed both numerically and as graphics. Matrices, international texts, Metadata are much easier to read.

* most profile elements from ICC specification version 2 and version 4
* additionally some widely used non standard tag are understood

ICC color profiles are used in photography, print and various operating systems for improving the visual appearance. A ICC profile describes the color response of a color device. Read more about ISO 15076-1:2010 Standard / Specification ICC.1:2010-12 (Profile version, color profiles and ICC color management under www.color.org .

The ICC Examin App is completely rewritten in Qt/QML. QML is a declarative language, making it easy to define GUI elements and write layouts with fewer code. In recent years the Qt project extended support from desktop platforms to mobiles like Nokias Meego, Sailfish OS, iOS, Android, embedded devices and more. ICC Examin is available as a paid app in the Google Play Store. Sources are currently closed in order to financially support further development. This ICC Examin version continues to use Oyranos CMS. New is the dependency to RefIccMAX for parsing ICC Profile binaries. In the process both the RefIccMAX library and the Oyranos Color Management System obtained changes and fixes in git for cross compilation with Android libraries. Those changes will be in the next respective releases.

The FLTK Toolkit, as used in previous versions, was not ported to the Android or other mobile platforms. Thus a complete rewrite was unavoidable. The old FLTK based version is still maintained by the same author.

Unbound RGB with littleCMS slow

The last days I played with lcms‘ unbound mode. In unbound mode the CMM can convert colours with negative numbers. That allows to use for instance the LMS colour space, a very basic colour space to the human visual system. As well unbound RGB, linear gamma with sRGB primaries, circulated long time as the new one covers all colour space, a kind of replacement of ICC or WCS style colour management. There are some reservations about that statement, as linear RGB is most often understood as “no additional info needed”, which is not easy to build a flexible CMS upon. During the last days I hacked lcms to write the mpet tag in its device link profiles in order to work inside the Oyranos CMS. The multi processing elements tag type (mpet) contains the internal state of lcms’ transform as a rendering pipeline. This pipeline is able to do unbound colour transforms, if no table based elements are included. The tested device link contained single gamma values and matrixes in its D2B0 mpet tag. The Oyranos image-display application renderd my LMS test pictures correctly, in opposite to the 16-bit integer version. However the speed was decreased by a factor of ~3 with lcms compared to the usual integer math transforms. The most time consuming part might be the pow() call in the equation. It is possible that GPU conversions are much faster, only I am not aware of a implementation of mpet transforms on the GPU.