linux-kernel - Re: [PATCH v4 09/12] [media] vivid: Local optimization

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Message-ID: <CAPybu_1XseCtoQdZ+k2mPYD4FrvsxxuDZPF00gZGJJowvy+o5Q@mail.gmail.com>
Date:	Mon, 18 Jul 2016 21:41:53 +0200
From:	Ricardo Ribalda Delgado <ricardo.ribalda@...il.com>
To:	Philipp Zabel <p.zabel@...gutronix.de>
Cc:	Jonathan Corbet <corbet@....net>,
	Mauro Carvalho Chehab <mchehab@...nel.org>,
	Hans Verkuil <hverkuil@...all.nl>,
	Markus Heiser <markus.heiser@...marit.de>,
	Laurent Pinchart <laurent.pinchart@...asonboard.com>,
	Helen Mae Koike Fornazier <helen.koike@...labora.co.uk>,
	Antti Palosaari <crope@....fi>,
	Shuah Khan <shuahkh@....samsung.com>,
	linux-doc@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>,
	linux-media <linux-media@...r.kernel.org>
Subject: Re: [PATCH v4 09/12] [media] vivid: Local optimization

Hi Philipp:

On Mon, Jul 18, 2016 at 4:16 PM, Philipp Zabel <p.zabel@...gutronix.de> wrote:

> I had the best looking result with this variant, btw:
>
>         y >>= 4;
>         cb >>= 4;
>         cr >>= 4;
>         if (tpg->real_quantization == V4L2_QUANTIZATION_LIM_RANGE) {
>                 y = clamp(y, 16, 235);
>                 cb = clamp(cb, 16, 240);
>                 cr = clamp(cr, 16, 240);
>         } else {
>                 y = clamp(y, 1, 254);
>                 cb = clamp(cb, 1, 254);
>                 cr = clamp(cr, 1, 254);
>         }

I like this variant much better than mine. I have applied to my local
tree. So it will be what I post on v5

Thanks for you comments :)


btw: it is scary what the compiler optimizations are capable of doing these days


-- 
Ricardo Ribalda