Default Demosaic Filter

When using a RAW capture source compressed to CineForm RAW (like the SI-2K), the development from RAW to 4:4:4 RGB involves selecting a demosaicing/debayer filter. There are a range of different filters to select from to create the look you need on a shot by shot bases.

Note: On Slumdog Millionaire they used a range of CineForm demosaicing filters to get the best sharpness per shoot -- better than post sharpening filters they stated.

With GoPro CineForm Studio Premium and Professional most CineForm RAW clips will show the debayer filter set to "Default". Default maps to "CF Advanced Detail 1" for 16/32-bit rendering or "Bilinear" for fast 8-bit playback. Yet some tools might render using 8-bit, and it is unlikely you want a bilinear demosaic for render (lower quality and not sharp.) If you set your clip's metadata to use a particular demosaic type, it will use that in all decodes (8 thru 32-bit, playback and rendering.) For smaller projects you can use the cut and custom-paste to quickly selectively paste just the debayer type to all your clips, but that becomes impractical for feature length projects. There is a registry control that sets the default demosaic of 8 and 16/32-bit decoding modes (for Advanced PC users.)

The registry is located
HKEY_CURRENT_USER/Software/CineForm/ColorProcessing/Default

You might see 0x0000ffff set or similar like 0x0000f7f3. The "ffff" part are the hexdecimal lower 16-bits that control the what Active Metadata features are active (globally.) These are reflected in this FirstLight control:

AMMask.png


<a href="http://techblog.cineform.com/wp-content/uploads/2010/06/AMMask.png"><img class="alignnone size-full wp-image-3037" title="AMMask" src="http://techblog.cineform.com/wp-content/uploads/2010/06/AMMask.png" alt="" width="158" height="180" /></a>

The upper bits 'AB" in 0x00ABffff control the demosaicing filters. The 'A' section selects the debayer filter for 16/32-bit decodes and the B section for 8-bit.

The filter number match how they appear in FirstLight:
<ul>
<li>1 - BiLinear</li>
<li>2 - Matrix 5x5 Adaptive</li>
<li>3 - CF Advanced Smooth</li>
<li>4 - CF Advanced Detail 1</li>
<li>5 - CF Advanced Detail 2</li>
<li>6 - CF Advanced Detail 3</li>
<li>7 - CF Simple Smooth</li>
<li>8 - CF Simple Detail 1</li>
<li>9 - CF Simple Detail 2</li>
</ul>
If you want "CF Advanced Detail 3" (number 6) to be you global default edit the "Default" registry entry to be 0x0066ffff.  For "CF Simple Detail 2" set 0x0099ffff etc.

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