Hello,
I have a show that did not pass the quality control at Discovery. Vidchecker report a few sequences for PSE problems. These are scenes of a live show, with a lot of strobes/flashing light. This is a final show, already cut, I can't go back to the original and change the edit.
What kind of color correction can I apply to avoid failing QC test ? Would lowering luminance or adding a "deflicker" or something helps ? Are there any plugins for this kind of job ?
Thanks,
What about slomo of 50%. I assume you've tried the stock frame/interlace/pull-down FX in AVID
Or:
Boris FX | BCC Flicker Fixer
Or: (not sure what works with AVID)
Best Video Flicker Removal Tools - Fixes Flickering Videos Quickly and Easily - (multimediasavvy.com)
I have a couple of friends who work at Discovery and they repackage shows for foriegn markets. I could ask them for any ideas, but they're generally are not allowed to use 3rd party plug-ins or have the latest MC. Us in our own world can.
Dan Powell - Take One Digital Media
If you can't slow it down a bit, drop the luminance and add a vignette if possible. Also may help to resize the frame slightly. Use a combination of these and hopefully you should get a pass. Vidcheck is checking for flashes over a certain percentage of the screen, so sometimes enlarging that helps, adding the vignette is also a way to "trick" vidcheck by decreasing the luma at the edges of the screen. Tweak until you have a pass. HTH
Andi
Also, depending on what type of fails you are getting (red flashes are a big one) then lowering the saturation may also help. Don't be surprised if the end result ends up looking total c**p, this is simply the trade off you have to accept when trying to get something to pass. I have seen Die Hard totally butchered in the UK in order to get the muzzle flashes from the rifles to pass the Harding (UK PSE manufacturer and probably the algorithm your vidcheck is using). Don't be surprised if you have to really be quite brutal in order to get a pass.
Also, they should be able to supply you with a copy of the Vidcheck report which will give you the exact frames and exact errors which you can use to pinpoint what's the problem. Sorry for the stream of consciousness, things keep popping up in the ol' noggin. I used to deal with this a lot as the UK have been very hot on PSE for years.
All right, will do! It's just a pain to have to resend a 90 min show for 5 clips and wait every time.
I know Netflix only check for PSE for animation, not features or docs.
Thanks a lot
Is there no way you can send them just the sections and ask them to run them? (make sure you give handles either side as vidcheck is also temporal and will take in to account how long a clip is too).
You could also contact Telestream for a trial of vidcheck?
http://www.telestream.net/telestream-support/vidchecker/download.htm
Good luck mate, I know what a pain it is!
I agree with Andi. Talk to the folks at Discovery about sending just the offending sections. I have done that in the past. You may need to find the right person to help, but it is possible.
Good luck,
Jef
_____________________________________________
Jef Huey
Senior Editor
Reducing luminance or saturation usually does the trick. I upload the offending sections (rather than the full episode) to Telestream Cloud QC to check the fixes.
That cloud service uses VidCheck and will generate a VidCheck report. There is no subscription sign up anymore, just pay for the minutes used.
https://www.telestream.net/telestream-cloud/quality-control.htm
I used to have to do a fair amount of Harding fixes for UK broadcast programmes.
As well as the suggestions mentioned earlier, you could try clamping the luminance, rather than reducing the whole picture level. I found that by setting luma clipping to around 50-60%, this would pass the re-test.
Using this method gave good results with things like camera flashguns. As long as your overall picture levels weren't too high, only highlights are really noticeably clamped, whilst the flashes were so momentary, that the limiting wasn't a problem.
PSE errors could also be triggered by repeated patterning, such as a chain-link fence. I found a bit of selective defocussing helped here.
Of course, picture cuts can also seen as a luminance change. Since these PSE checkers are counting the number of luminance changes per second, sometimes moving a cut a few frames earlier/later fixed the problem.
Using the Vidchecker cloud service is a good way to do your own tests for sure.
HArding now have an Avid plugin that allows anaylsis directly in the timeline. Pretty neat I have to say.
Broadcast & Post Production Consultant / Trainer Avid Certified Instructor VET (Retired Early 2022)
Still offering training and support for: QC/QAR Training - Understanding Digital Media - Advanced Files * Compression - Avid Ingest - PSE fixing courses and more.
Mainly delivered remotely via zoom but onsite possible.
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