On Fri, Oct 17, 2014 at 10:26 AM, Larry Gritz <[email protected]> wrote:

> That's another possibility I would entertain -- automatically upgrading
> the subsampling when a sufficiently high quality is requested.
>

This seems too magical to me. Those who are setting subsampling levels are
probably expert users and probably thus want what they are asking for
explicitly.

I set the default quality for jpeg output (if no "quality" attribute is
> found) quite high, 98. I'm also happy to revisit whether that's too much. I
> can't say it was a principled reason for that particular value.
>

Back when we used 8-bit jpegs in production, they were quality 98, and we
moved over time from 4:2:0 to 4:4:4. When we used "16-bit" jpegs (actually
12-bits internally) we used 4:4:4 and quality of 75. Some tests determined
that quality of 75 in 16/12-bit looked as good as 98 in 8-bit.

Anyway, just data points using jpeg images in animation production.

I'd vote the default to be 4:2:0 since that's what most devices write.
Those who want 4:4:4 are more likely to understand these settings.

--jono
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