Yellow streaks on rendered video

[Vaporetto Italiano_- 2255]

Hi,

I notice some yellow spots and streaks in some parts of my videos (see photo attached). They're very visible when I stop the video, but almost impreceptible when I watch it. What could this be? They are not present in the original video.

The video is shot and edited on a Mac at 25fps.

Thank you!

Francesco

[Peru Bob]

It could be a watermark of a third party effect that is in trial mode.

[Vaporetto Italiano_- 2255]

Thanks for your reply. It doesn't appear for the all lenght of the video, but a few times and just for a fraction of a second. Could a trade Mark do this?

Thank you again!

[R Neil Haugen]

Banding of the image, perhaps? They are very subtle, and seem to be across the areas where there is a slight brightness gradient.

What is the media ... perchance 8 bit long-GOP mp4?

[Vaporetto Italiano_- 2255]

Yes, but they don't appear in the original video 😍

[R Neil Haugen]

Of course they don't appear in the original video ... if banding or macroblocking, it's when you do anything to the file, tonal or color changes, or re-encode again. Then the banding and macroblocking become visible.

So back to my questions which you didn't answer ... what is the media, especially, is it 8 bit long-GOP mp4?

And btw, Mark's comments are about the same thing.

[Vaporetto Italiano_- 2255]

It is 8 bit long-GOP mp4. Thank you for your reply!

[Vaporetto Italiano_- 2255]

Unpdate. If I paly the video with VLC, instead of Quick Time, the yellow stripes appear in different parts of the video and are less frequent. I really thank you for your help!

[Vaporetto Italiano_- 2255]

No, now they appear with both players aaha

[R Neil Haugen]

Oh yea ... 8 bit long-GOP, so there's not that much data left from the compression process. And when you have any 'smooth gradients', especially in lighter areas, this can happen. And will if you do much tonal/color correction at all.

Sometimes you can minimize this appearing in an export, by going to higher profile, level, and bitrate settings at export if you export to H.264 again. It's a real bugger to work with though.

The exposure and contrast settings of the camera, and lighting, really need to be spot-on to get good media to work with from cameras limited to that format. If it's got anything higher quality, use it.

[Maks Histibe]

Hi Francesco,

It sounds like this could be an issue related to color or compression artifacts, especially if the yellow spots are visible in still frames but not as much in playback. Sometimes, exporting settings or preview renders can cause slight color inconsistencies, particularly in compressed formats. Here are a few things to check:

1. Render Settings: Ensure the render settings match the original quality and color profile of your footage.
2. Playback Resolution: If you’re viewing at a lower playback resolution, it can sometimes alter colors or cause artifacts.
3. Export Format: Try exporting in a higher quality format (like ProRes) and see if the artifacts persist.

Let me know if these help or if you see any patterns based on playback or export settings!

[Vaporetto Italiano_- 2255]

Thank you very much! I'm not an export, so how do I check the color profile in the original video? 😰

[R Neil Haugen]

Click the clip in the bin, right-click Properties.