Date: Sat, 11 Jan 2014 18:22:57 +0000
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Jean-Francois Moine <moinejf@free.fr>
Cc: dri-devel@lists.freedesktop.org, Rob Clark <robdclark@gmail.com>,
        Dave Airlie <airlied@gmail.com>, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2 16/28] drm/i2c: tda998x: change the video
	quantization
Message-ID: <20140111182257.GE15937@n2100.arm.linux.org.uk>
References: <20140109120500.6abc6cd2@armhf>
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On Thu, Jan 09, 2014 at 12:05:00PM +0100, Jean-Francois Moine wrote:
> This patch changes the video quantization to RGB/YUV.

Strong NAK, this patch is definitely incorrect.

The Cubox (which I assume is the platform you're generating these patches
for) produces RGB at it's output, which are the RGB values from the
framebuffer.  Being a computer-like "IT" source, these RGB values have the
full range, from zero to 255, rather than the limited range of 16 to 235.

With limited range, a value of 16 is black and 235 is white.  However, the
values in the framebuffer will be zero for black and 255 for white.

A VQR value of 1 gives limited range of 16 to 235, whereas zero gives
full range.  The value of zero is correct here.

-- 
FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up.  Estimation
in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad.
Estimate before purchase was "up to 13.2Mbit".
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