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<blockquote data-quote="bigj" data-source="post: 234419" data-attributes="member: 10940">Apparently the correct way to compensate is at the display side.i.e. you accept that the device (HTPC) is outputing whatever it is and then adjust your TV/Projector so that &lt;16 is absolute black and &gt; 235 is over white.The problem is that with an HTPC which is designed with other content (the GUI) authored to use full 0:255 you'd loose detail in dark GUI artwork and clamp the bright bits.The solution is to either author (or blit adjust) GUI for 16:235, which is unlikely! or to bite the bullet and expand the VMR texture from 16:235 to full 0:255. I hope MPII provides D3D colour transformations (brightness, contrast) that will allow this.The reason for using the device to adjust: Supposedly the expansion from 16:235 to 0:255 at the source end introduces banding. But I've not done any tests to confirm how bad this is (over allowing the device to do it.) Perhaps the device has &gt;8bit precision or has analog expansion? Anyway, at the end of the day I can't really see any alternative but to expand the VMR source for an HTPC.And I wonder if/why overlay expansion would be any better in this scenario (of overlay window within a GUI) - i.e. If using DVI then isn't that 8bit channel? so even overlay video over GUI is still 8bit total precision surely...(with the overlay content just being expanded from 16:235 to 0:255)?</blockquote>

[QUOTE="bigj, post: 234419, member: 10940"] Apparently the correct way to compensate is at the display side. i.e. you accept that the device (HTPC) is outputing whatever it is and then adjust your TV/Projector so that <16 is absolute black and > 235 is over white. The problem is that with an HTPC which is designed with other content (the GUI) authored to use full 0:255 you'd loose detail in dark GUI artwork and clamp the bright bits. The solution is to either author (or blit adjust) GUI for 16:235, which is unlikely! or to bite the bullet and expand the VMR texture from 16:235 to full 0:255. I hope MPII provides D3D colour transformations (brightness, contrast) that will allow this. The reason for using the device to adjust: Supposedly the expansion from 16:235 to 0:255 at the source end introduces banding. But I've not done any tests to confirm how bad this is (over allowing the device to do it.) Perhaps the device has >8bit precision or has analog expansion? Anyway, at the end of the day I can't really see any alternative but to expand the VMR source for an HTPC. And I wonder if/why overlay expansion would be any better in this scenario (of overlay window within a GUI) - i.e. If using DVI then isn't that 8bit channel? so even overlay video over GUI is still 8bit total precision surely...(with the overlay content just being expanded from 16:235 to 0:255)? [/QUOTE]

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