David Esp Video Technical Blog

Boris RED 5.0.6: Retiming & Velocity experiments continued.

A new day, restarted the Boris RED 5 (Engine), started a fresh project, altered many settings.

No success.  Always the same issue: if frame-interpolation happens, due to pseudo-increased framerate or pseudo-slomo, then exported frames are in the wrong order.  Only if neither framerate increased nor velocity reduced does it look correct.

I give up until a fix or workaround appears…

Steps:

• Project 1080@25fps, Source 1080i50 (in AVI-Cineform) acting as input to Source Layer of Optical Flow filter:
  • Optical Flow: [Velocity 100%, Fields: Upper, Input FrameRate 25fps, FLow Quality: Medium.
    • Render: [MovieType: AVI-VFW, Field: Upper, Scale: Full, Quality: High, FrameRate: 25.00, Compression: Uncompressed, 1920×1080]
      • Result:
        • As expected
          • Looked and played basically OK.
          • Slight blurring and (on close inspection on fast zoom-out) combing – which here is good news since this is what would be expected for interlaced material being viewed on a progressive player.
        • File Size: 235 MB
      • Render Time: 15 seconds (measured on iPhone Clock>Stopwatch)
    • Render: (same but this time Progressive)
      • Result:
        • Broadly as expected, maybe a tiny bit dissapointed (or possibly my expectations are excessive)
          • Looked and played basically OK
          • No combing visible
          • However on fast-zoom-out there was what looked like frame blending going on, I guess that might indicate where the Optical Flow gave up and fell back to that cruder method (?).
        • File Size 25 MB (same as previous)
      • Render Time: 14 seconds
    • Render: (same but FPS not as Project (uncheck, each time) but rather 100fps.
      • Result:
        • Same as previous
        • The desired export FPS setting appears to have been ignored.
• Project: (same as previous but 100fps)
  • Optical Flow: (same as previous)
    • Render: (same as previous, except this time no need to un-check “as Project”)
      • Result:
        • Correct image but incorrect frame order, resulting in a “shuttling” effect.
          • Looks like it goes forwards with frame-blending then backwards with proper optical flow.
            • Guess: Maybe it’s a software bug where the interpolated frames are computed by both methods, in the observed opposite orders, but subsequently not recombined properly (?).
• Check for Product Updates:
  • http://www.borisfx.com/register/download/esd_red.php?id=1617952
    • Should have done this earlier…
    • Latest for 64-bit is the one I have, namely 5.0.6
    • There exists also 5.0.9a but its ReadMe only lists fixes for Edius (irrelevant to me) and the dropdown for it mentions 32-bit but not 64-bit, leaving me uncertain whether I should apply it.
      • I’ll play safe and refrain from applying it.
      • I emailed Boris Support (with screenshot of dropdown) for their clarification.
• Project: (same as previous but 100fps)
  • Tried various other options in Optical Flow, but always the same frame-ordering error:
    • [Optical Flow Quality] = [Medium], [High] and [Best]
    • [Blending] = [Frame Blending Only], [Bi-Directional Mix], [Nearest Mix]
    • [Optical Flow Mix] = 0 and 100
  • Also, in Render settings, tried disabling [Better Quality Field Rendering]
• Determined that:
  • The “wrong frame order” effect only happens when Optical Flow is attempting to interpolate frames as part of increasing the pseudo fps or slow-motion.
  • It does not happen when there is no change made to both framerate and velocity.
• I give up!
  • Until Boris or anyone fixes it or indicates a workaround…

This entry was posted on Wednesday, January 4th, 2012 at 12:10 and is filed under Boris, retiming, velocity. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.