HD For Indies

UPDATE SATURDAY MORNING on StEM footage actual resolution

FedEx guy was busy this week - I got two key things:

1.) The DCI StEM footage - this is the Digital Cinema Initiative Standard Evaluation Material. It is a little mini-movie they shot on film and carefully scanned at 4K (4096x3072) and carefully color corrected and saved out as 16 bit RGB TIFF files. I bought the 2K (2048x1536) version since that's as much data as I can reasonably work with.

UPDATE SATURDAY MORNING: It's 2K wide (2048), but only 857 or so pixels tall. BUMMER! This is about half the vertical resolution I was expecting. It's 2.4:1 aspect ratio, widest cinema aspect used. So for HD, I've got to letterbox it. So all the anamorphic scaling stuff below is WRONG. I just dropped it into a 1920x1080 comp, let the sides crop off, and let there be black top & bottom. Sniff

My plan is to convert that to various HD formats: 720p, 1080p, and 1080i sizes at 4:2:2 YUV and 4:4:4 RGB color space, and at 8 and 10 bit color depth. Probably about a terabyte of test files by the time I get done. Then I plan to convert it to various codecs (uncompressed, DVCPRO HD, HDV, and maybe DNxHD if I can figure out how) to see how it all holds up. The footage was all shot to specifically test for the things that digital tends to screw up on, so should be very interesting to see the results. It just dawned on me - this stuff might be logarithmic instead of linear, I'll have to deal with that, too. My "punt" position that I'm pretty sure will work:

1.) Batch all 16bit RGB TIFF files to 16 bit PSD (Photoshop) files, because I don't think After Effects can handle 16 bit TIFFs (need to verify)

2.) Import the numbered RGB PSD files into After Effects as a clip

3.) Drop those into a 1920x1080 comp and scale them to fit (they are anamorphic 2048x1536). I'll also create a 1280x720 comp.

4.) If the footage is linear, I'll have to install and figure out eLin (from Red Giant Software) to "de-log" the footage into a linear colorspace. I think that's something eLin can do, I'm not absolutely positive though.

5.) From there, I can render out all my 1920x1080 stuff:
1920x1080 @ 24fps 8 bit 4:2:2 uncompressed
1920x1080 @ 24fps 10 bit 4:2:2 uncompressed
1920x1080 @ 24fps 10 bit 4:4:4 uncompressed
1920x1080 @ 60i 8 bit 4:2:2
1920x1080 @ 60i 10 bit 4:2:2

....and so forth and so on. Those will be my digital masters for codec testing, to see how much each codec shreds the footage from the original.

I'd like to try messing with Cleaner for it's superior scaling algorithm, but I fear it's YUV conversion - I've seen some wierd results when working with DVCPRO HD codec. Also, I don't think it can handle 16 bit anything.

I'd like to use Compression Master, but again I don't think it could use the 16 bit source to compress down to.

I might end up making some kind of interstitial at 10 bit from AE at full size and do the scaling and codec writing from Compression Master or Cleaner, again I'll have to make a short test and fool with it...lots.

Debabelizer has an excellent scaling algorithm as well, but I don't know if it handles 16 bit anything either.

If anyone has any clues on any of this, I'd LOVE to hear from you at mike AT hdforindies DOT com.



2.) I also have sitting patiently on the shelf a SyncRAID XL card that I want to doodle with and see what kind of realworld performance numbers I can obtain from it. I'm thinking that might end up being a card in my server as a secure RAID 5 type setup to backup all this test data I'm generating. I have 5 160 GB drives sitting around, I could get 600 GB of protected RAID out of that. If I don't make all the 1080i variants, I could fit it all on there. Hmm....

-mike