water pixelation

I'm probably not using the proper terminology, so I was unable to find a reference to the topic...sorry.

When color correcting in FCP, I can get the colors to appear as desired. However, the application of the CC filter, the contrast filter, etc., yield patchy pixelated zones in the background water column (the problems are further augmented by compression). Can anyone direct me to a source that addresses controlling the apparent filtration artifact?

Sounds like you're talking about "macroblocking". Search "blocking" or "blockiness". It's also known as tiling, mosaicing, pixelating, quilting or checkerboarding. But you might be talking about "banding", which is a common compression artifact on blue water.

First thing to try is more bitrate.

What format is your footage? What codec are you editing with?

Thanks for the synonyms. That was very helpful. I think that I got some improvements with the Reduce Banding filter, although the effect was incomplete at youtube levels of compression with H.264.

The issue almost entirely disappeared while exporting with 422 hq (same as import) through QT Movie, whereas it was quite noticeable with QT Conversion (which I would now expect).

Any suggestion as to optimal parameters for the Reduce Banding filter? This would seem to be my best hope for a decent result on the higher compression exports.

Sounds like you're talking about "macroblocking". Search "blocking" or "blockiness". It's also known as tiling, mosaicing, pixelating, quilting or checkerboarding. But you might be talking about "banding", which is a common compression artifact on blue water.

 

First thing to try is more bitrate.

 

What format is your footage? What codec are you editing with?

Thanks for the synonyms. That was very helpful. I think that I got some improvements with the Reduce Banding filter, although the effect was incomplete at youtube levels of compression with H.264.

 

The issue almost entirely disappeared while exporting with 422 hq (same as import) through QT Movie, whereas it was quite noticeable with QT Conversion (which I would now expect).

 

Any suggestion as to optimal parameters for the Reduce Banding filter? This would seem to be my best hope for a decent result on the higher compression exports.

Sounds like it is an encoding issue based on your targets if you really are not seeing it on 422HQ Exports for the most part. If you are loading to youtube there are tricks to make things look better, though there is compression going on there. If the video is short enough and small enough you may be able to upload a less compressed version. I do not have some setting I found worked well in front of me, but will try to post them. FWIW, if you export from FC as self contained then use Compressor, you can often save some time on test encodes....

Great suggestions. Thanks for the further insight.

Sounds like it is an encoding issue based on your targets if you really are not seeing it on 422HQ Exports for the most part. If you are loading to youtube there are tricks to make things look better, though there is compression going on there. If the video is short enough and small enough you may be able to upload a less compressed version. I do not have some setting I found worked well in front of me, but will try to post them. FWIW, if you export from FC as self contained then use Compressor, you can often save some time on test encodes....

Search for a post Steve Douglas put up about encoding in Compressor for Vimeo and You Tube etc. Those are the settings that I still use and they give a good balance between file size and quality for uploaded video content.

Cheers, Simon

Here is the url for my article on compressing for Vimeo or Youtube. http://www.kenstone.net/fcp_homepage/vimeo...or_douglas.html

Always avoid using reference movies or 'send to Compressor'. Also, avoid using the Quicktime Conversion. Just export your film short as a self contained QT mov file and then bring into your Compressor app. As a compromise you might want to have DVD Studio Pro markers checked rather than regular chapter markers. Not sure why you feel the need to use Pro Res HQ unless you are shooting on a Red One or a cam of that quality. HQ creates huge files and HQ will not necessarily provide any better quality for you that regular pro res 422 or even LT. I see banding most often in the blue of water in WA shots. Banding is caused during compression. It's a compression error (higher bit rates help). Blue skies are problematic as well as underwater shots.

Remember that filters reduce the resolution of clips ever so slightly so be prudent about their use.

Hope the article works for you

Steve

Thanks, everyone, for the input. Thanks, Steve, for the link to the article.

I'll be out of contact for a while as of tomorrow, but I'll report back in due course.

Happy holidays!!!

Here is the url for my article on compressing for Vimeo or Youtube. http://www.kenstone.net/fcp_homepage/vimeo...or_douglas.html

 

Always avoid using reference movies or 'send to Compressor'. Also, avoid using the Quicktime Conversion. Just export your film short as a self contained QT mov file and then bring into your Compressor app. As a compromise you might want to have DVD Studio Pro markers checked rather than regular chapter markers. Not sure why you feel the need to use Pro Res HQ unless you are shooting on a Red One or a cam of that quality. HQ creates huge files and HQ will not necessarily provide any better quality for you that regular pro res 422 or even LT. I see banding most often in the blue of water in WA shots. Banding is caused during compression. It's a compression error (higher bit rates help). Blue skies are problematic as well as underwater shots.

 

Remember that filters reduce the resolution of clips ever so slightly so be prudent about their use.

Hope the article works for you

Steve