Sunday, April 28, 2013

Codecs and Bit Depth (as a reminder)

COLOR SCIENCE
RGB Codecs sample each base color, with no Chroma subsampling.
Ex. ProRes4444, HDCAM SR Dual Link.
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Y'CbCr Codecs use Luma sampling + Chroma subsampling.
Vertical and Horizontal resolution is indicated by the last two numerals:

4.4.4 use uncompressed Chroma subsampling 

4.2.2 use compressed, (1/2 vertical and 1/2 horizontal resolution) Chroma subsampling (Ex. ProResHQ, ProRes422, ProResLT, ProResProxy, ACV-Intra 100, XDCam422, Canon MXF422, DVCProHD and DVCPro50, DBeta)

Prosumer also use 4.2.0 (HDV, AVCHD, AVC-Intra 50, DVCam PAL, Mpeg2-DVD) or 4.1.1 variants (DV, DVCPro, DVCam NTSC)

Reduced Chroma subsampling makes smaller file sizes = More storage efficiency, but creates image artifacts (halo, color bleeding/smudging on edges.)

BIT DEPTH
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8 bit Codecs are 24 bits image files.
RGB 8 bits for each base color, intensity range: [0-255].
A pixel that's [0,0,0] is black, a pixel that's [255, 255, 255] is white.

Y',Cb,Cr has a different intensity range [16-235] to allow for super white/black.
Limited range problematic especially for gradients (stepping.)

Ex. 8 bit Codecs:
Uncompressed 8bit, HDV, DBeta, ProResProxy, DV, DVCPro, DVCam, Mpeg2. 

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10 bit Codecs are 32 bits image files = 10 bits for each base color (RGB) +2 spare bits. Intensity range: [0-1023]

Y',Cb,Cr has a different intensity range [64-940] to allow for super white/black.

Ex. 10bit Codecs:
Uncompressed 10bit, ProRes4444, ProResHQ, ProRes422, ProResLT, AVC-Intra 100, Canon MXF422.

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10 bit LOG (Cineon, DPX) is equivalent to 12 bit Linear, but values are Log-curve compressed to match the film emulsion sensitivity to light which is logarithmic. This allows for a wider dynamic range by rolling-off the highlights that would be otherwise clipped in 8, 10, even 16 bit linear capture. Film print density range higher than 1080 values
Intensity range: [0-?] for each color. (Eq. 12 ƒ-stops.) Ex. Film scans.

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12 bit Codecs
Intensity range: [0-?] for each color. Ex. RED One.

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16 bit Codec are 48 bits image files. 
Intensity range: [0-65535] for each color.

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Floating point is only for processing images, not storage. Better, more precise maths for calculation = higher quality results. Intensity range: [?-?] (Eq. 25 ƒ-stops.)

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ACES "unlimited" (Eq. 30 ƒ-stops.)

Tuesday, April 23, 2013

Canon 5D MarkIII funky TimeCode

I believe the Canon 5D MarkIII has a funky TimeCode track, which wreaks havoc in FCP7 Log & Capture.  L&C wrongly shows clips with a duration of 23h+, or does not transcode some clips, what the heck?

Some people use an 3rd party app to convert the h264 to ProRes. But some apps loose TC (Compressor, Mpeg Streamclip), read it wrong (Brorsoft Video Converter), or have the user insert TC by hand (Grinder). I don't like it. 5DtoRgb works fine, but for an online/offline workflow, multicam situation, a 3rd party app is not ideal - I prefer Log&Transfer and to stay within FCP.

After reading Oliver Peters' blog I had the idea that Canon's TC track was to blame.
http://digitalfilms.wordpress.com/2010/10/09/easy-canon-5d-post-–-round-iii/

So I made a copy of the files, ran them through VideoToolShed's QTChange and the Refresh TC Track tool.  http://www.videotoolshed.com/product/42/qtchange

Bingo! The new set of file is perfectly recognized and transfers smoothly with Log&Capture, including TC.  Thank you Oliver, thank you Bouke.

Monday, March 25, 2013

Panasonic AF100 Post

Macs can read SD cards, so no driver required. Same as with P2 cards.
This camera uses AVCHD, so it's already populated by default in the FCP7 Log & Transfer.
Panasonic white paper here:
ftp://ftp.panasonic.com/pub/panasonic/Drivers/PBTS/papers/Editing%20AVCHD%20with%20Final%20Cut%20Pro%207.pdf

I prefer ProRes 422. But I'll use LT for some projects. Or Proxy for offline/online.

Sony EX3, EX1 XDCAM Post

Sony software for working with XDCAM footage:
https://www.servicesplus.sel.sony.com/sony-software.aspx

You need to create a pro account in order to download some of it.  There are plug-ins for Avid and FCP7 (via Log&Transfer), a clip browser and a SXS card driver.
Someone had listed the steps on his own blog/website (links do not work anymore though, so go direct to Sony Service Plus link above.)
http://www.pauljoy.com/2009/03/2230/

Monday, March 4, 2013

AME Settings

AME Settings
Adobe Media Encoder is rather fast at transcoding. Results seem decent. So why not use it more.  The Export Settings is not very intuitive  though.

1- Check "Render at Maximum Depth" box if you want 10bit processing, else it's limited to 8bit.
2- Don't bother converting between frame rates, it's crap.
3-The "Aspect" drop-down menu selections are for the OUTPUT. Can't see how to force the Source AR.  Do you?  Someone?  Adobe?
3- Don't forget to set the Audio properly in the Audio tab - I use 24bit but it's 16bit by default.

Thursday, February 28, 2013

Apple Cinema Tools Inverse TK

For the life of me I can not get proper inverse TK on this clip. I tried several times, I selected a few different A frames, no luck.

Wait a minute... That little check box that you're supposed to leave selected...

Well, since my result is crap, I fall into the category "does not produce the correct result" don't I?

Let's try to uncheck the bugger...

And you know what? That was it! It works! Done clean, beautiful!

Why the misleading? Why oh, why?


Friday, February 8, 2013

Apple Motion Retiming

In Apple Motion, to properly retime footage, import Media, drop into the timeline. Click+Option at the end of the clip and extend to the desired length. (Trim bracket turns into stopwatch.)
Select the Media, open Properties tab. Expand Timing property.  In Frame Blending select: Optical Flow.

When rendering the .mov, don't forget to check Frame Blending.