Coloured Squares around High-Contrast areas after export ???

[Brad Elliott]

The artifacting that you are seeing is usually caused by the following:
1) The data rate
2) Colors/whites are too hot

No matter what the pixel dimensions of your file the data rate generally has the largest control over quality/size of your finished file.

I have had problems with compression that couldn’t be easy explained and thought it was the codec that I was being asked to use. After checking my sequence in a waveform and vectorscope it was determined the whites and reds were too hot. Adding a broadcast safe filter and making some color adjustments solved the problem.

Where will your final deliverable be used?

[Charlie Reader]

Hi Brad,

Sorry for getting back to me and apologies for my late response.

I used Handbrake to encode the master, using constant quality rather than setting a bitrate target. I also used scopes when grading the video so am fairly sure that it’s all broadcast legal, although saying that I set black to 0/0.3 as it isn’t going on television (only internet release), but this hasn’t been a problem for any of my videos before using the same compression settings.

I will try what you said anyway though!

Thank you

[Jeff Greenberg]

Handbrake is a great automated tool for ripping DVDs. And while it ‘works’, it’s not the tool I’d ever pick of choice. The Constant quality settings aren’t always what you’d really like.

What it looks like happened is that you exceeded the data rate needs (handbrake guessed them wrong.) Do you have other tools? I’m assuming you have compressor, because you’re handling a ProRes 4444 file. How about giving it to compressor and using the Youtube setting? Just compress that one scene (did you know you can set an in/out in compressor? It’s great to test a difficult section of your video.) to test.

Last, I have seen problems like this with a corrupted QuickTime file or corrupted render, but that’s not terribly likely.

Best,

Jeff I. Greenberg
Author/Master Instructor/Speaker/Consulting
My contact info and more
New! Come see me speak @ NAB/Post Production World!