Archive for August, 2012

Cineform and Alpha Channels

Friday, August 31st, 2012

The full (paid) version of GoPro-Cineform Neo (as I have) does support alpha channels.

(A colleague initially thought otherwise – but that impression turned out to be based on info from old forum threads)


Chroma Upsampling (Chroma Interpolation)

Friday, August 31st, 2012

Shooting green-screen onto a 4:2:0 chroma-subsampled format, intending of course to use it for chroma-keying.  Obvious disadvantage is green-ness of green-screen only gets sampled at quarter-resolution.  Not a show-stopper, given my target deliverable is standard definition, but anyhow, towards perfectionism, is there any way to up-sample to 4:4:4 i.e. full definition colour?

It does occur to me that something more sophisticated than chroma blur ought to be possible, broadly along the lines of edge-following methods employed in resizing. What’s out there?

  • Simplest method, that most people seem to use, is chroma-blur.  That’s only the chroma, not the luma.
  • Searching around, Graham Nattress has analysed the problem and seems to have produced a more mathematical approach.  But it’s only available (at time of writing) for Final Cut (which of course is Mac-only at present).

Some tools that “promise” upsampling, but I wonder by what methods:

  • GoPro-CineForm intermediate.  The codec settings include an option to up-sample to 4:4:4
  • Adobe Premiere, but only if a Color Corrector effect employed.
    • But the crucial thing here, regarding the usefulness of this, is whether it uses any better method than chroma blur.

Some questions:

  •  Does Adobe have anything built-in to do something Nattress-like nowadays?
  • DaVinci Resolve?
  • Boris?


Adobe Prelude – Usage in Newsroom Context

Monday, August 27th, 2012

I don’t work in or for a newsroom as such, but I do cover live events.

The Mars Underground (2011)

Saturday, August 25th, 2012

As a child I watched in awe the live Apollo moon-missions.  No single thing gave me more admiration for the USA than this, and I was not alone.  Desolate decades followed, of introverted application of far greater sums of money and amounts of energy on transient and unimpressive efforts, on earth and in low earth orbit, the potential just evaporating into nothingness.  Cynicism and opportunism of the new age questioned even that the moon missions had ever happened.  Not that hard to appreciate, given that nothing in space on such a brave and imaginative human scale had happened since.  Great robots and probes, but…

The practical possibility of exploratory missions to Mars was demonstrated decades ago.  Yet nothing happened.  The obstacle: neither technical nor financial, just establishment politics, inertia, entrenchment, fear.  Now, with the success of the “unlikely” technology of the Mars Science Laboratory (MSL) (“Curiosity”) landing, something has re-awoken.

It is time to recognise, remember and reiterate the potential.  Hopefully I’m contributing at least a tiny element to that spirit here, in my lowly video-technology blog.

This is the hope:


USB3, eSATA, Thunderbolt: Comparison: I like the look of eSATA

Sunday, August 12th, 2012

Mac OS Maintenance Tips for Speed

Saturday, August 11th, 2012

Mac OS: File Stocktaking: Equivalent of TREE (as in DOS)

Saturday, August 11th, 2012

How, on a Mac OS system, to do the equivalent of TREE in DOS:

  • find . -print | sed -e ‘s;[^/]*/;|____;g;s;____|; |;g’
    • And there is much more on ths in the article, including how to add this “command” to user profile.

My crude adaption of it, to list only the main directories in my [Media] area:

  • find . -type d \! -name “BPAV” \! -name “CLPR” \! -name “TAKR” \! -name “929*” -print | sed -e ‘s;[^/]*/;|____;g;s;____|; |;g’
    • Crude but delivered what I wanted.

Kinefinity’s KineRaw S35

Thursday, August 9th, 2012

Last night the thought came, if only I could justify getting a Sony F3…

Now possibly the answer to my dreams?  The forthcoming (next year, hopefully) KineRaw S35, by some people’s judgements, is broadly comparable to an Arri or RED but at half the price.  That’s broadly not exactly.  Yes, it’s from China..   I heard about it first from the highly informative NoFilmSchool (well worth joining).

This camera, nearing the end of its development and testing, shoots Raw (straight colours, no debayering), which to naive me sounds like big bandwidths and files, but as it happens, one of its options is to record to GoPro-Cineform RAW (10-bit log90) format.  This, if I read the article by Jake Seagraves (as of 9 August 2012) correctly, for a 2K frame, has typically the same bandwidth as GoPro-Cineform HDV (1440×1080), namely/numerically around 15 MB/sec (=120Mb/s).  I say typically because it is a Variable Bit Rate format, so obviously it depends on scene (including noise) complexity.   By comparison, HDV 1440×1080 m2t (long-GOP Mpeg2), like DV, are about 25Mb/s.  So Cineform is then about 5 times bigger than HDV and DV – the unavoidable cost of being “visually lossless”.

Some informative links I chanced upon:

  • Brief specs:
  • Main Site (still being edited at time of writing):
    • “…the Vimeo version is a shadow of the image quality the uncompressed footage can show since to post on Vimeo I need to compress MPEG4v2 and that mucks up the image with block artifacts…”
    • Yes I can pull the shadows up maybe 3 to 4 stops without major issues and perhaps 6 stops if you apply more forcefull noise reduction in post. The maximum would be about 8 stops of lift but probably not for Blu-ray use as compressed end use formats need noiseless result frames.
    • Some cameras use temporial noise reduction in the camera to get lower noise at high ISO, but these are raw recording cameras so you would use temporal noise reduction as well as area filters and chroma cleaners as a normal part of post production, so take that into account.
    •  35mm film scans are now ‘always’ de-grained and dust-busted with powerful software to get a usable result, most people don’t know how much grain ‘raw’ film scans can show because all they see are heavily digitally processed film scans. Likewise a True RAW recording Digital Cinema Camera gives you ‘raw’ DNG that are like raw film scans in that they should undergo de-grain and filtering to make the results look better, …
    • Cineform ™ is like RED ™’s REDCODE ™ in that it is wavelet compression
      • Sensor: the 2K model has a 4K sensor, downscaled by pixel-binning (hence all pixels get used).  Moire/Detail tradeoff optimizable by customizable Low-Pass-Filter (LPF).  CMOS hence rolling-shutter.
      • Exposure: Around 12 stops of latitude.  Base ISO is around 800, variable from 8 to 10,000 (above which noise becomes a problem).
      • Hardware: Has a fan, its speed/noise depending on temperature.  No battery of its own, just a (standard) power socket.
      • Audio: Two XLRs but they are only line-level (no mic, let alone phantom…)
      • Video: Two SDIs BUT these are only intended for monitoring, e.g. they only carry 8 bits.
      • Weight is around 4 kG.  Not as light as an F3 but not as heavy as an Arri.
      • Recording: Own-brand KineMag SSDs are only needed for “True Raw” DNG recording (800 MB/s), alternatives can be used for Cineform RAW recording (around 100Mb/s VBR).
      • Monitor outputs e.g. to feed SmallHD monitor (or others), include overlays for Waveform Monitor, Histogram (with separate colours), Zoom (e.g. for focus assist) up to 800%

Mac Pro Disk Failure & Recovery

Thursday, August 9th, 2012

Computer increasingly slow on start-up, eventually becomes sporadic in its ability to succeed, unexpected error messages…

Yes, it’s Disk Failure Time !  This time it was on my Mac Pro (desktop)

So I did these things:

  • Copied latest stuff to a portable (WD Passport) drive:
    • I copied documents, videos and downloads
    • I generated a list of installed applications, both 32-bit and 64-bit.
  • Opened up the machine to remove drives (and at the same time to hoover-out dust).
  • Procured a replacement hard drive
    • Google-search revealed my old drive to be obsolete, no longer (easily) available
    • Phoned a local computer tech wizardry shop, who fix Macs as well as PCs, and they had a suitable replacement drive (a WD SATA 1TB drive, twice the size of the old/failing one.
    • Bought that very disk.
  • Fitted the disk, as sole disk, and recovered both the Mac OS and Boot Camp > W7 partitions, according to the “DO” (not “DON’T”) branch of the instructions listed at
    • It took about an afternoon.  The longest stages were the actual restorings from backup.
  • For W7
    • The first thing I updated was the antivirus.  This was for the app as well as the database, and it wasn’t quick.  No reboot needed though.
    • Otherwise, two or three reboots were required, including first-use, windows updates critical, windows updates optional.