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Re: Measuring colours accurately in mobile apps

for

From: Patrick H. Lauke
Date: Jun 23, 2021 1:03AM

We generally go down the "take a screenshot on device, then transfer it
to a desktop/laptop device for traditional testing with CCA or similar"
path, despite its potential flaws (for instance, even taking an
on-device screenshot can lead to specific colour profiles/adaptations on
the device being applied, making the colour drift slightly). And you're
exactly right, other methods like Zoom, Reflector, or similar will
compress the video leading to changes in colour, and should always be
avoided.

When emailing, if given the option, go for "original" rather than any
email client resizing. That should guarantee that it takes the raw
screenshot that was saved, without any further recompression.

There's no (legal/legit) way to grab an app from the app store/google
play store and then decompiling it (especially since these apps are
digitially signed etc when packaged).

When reporting on colour contrast failures (and luckily, we only do
failures, and don't list all colour combos including passes) we also
include wording that explains the values are approximate, based on
having to test what was available to us. If a client wants more
precision/certainty, we ask for actual accurate colour values they used,
or request that they give us access to a development build/XCode
project/similar to open in an actual development tool.

P
--
Patrick H. Lauke

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