After Effects – Flickering problem with noise effect

[Kalleheikki Kannisto]

Possibly an export setting: If you are exporting with a format that uses lossy compession and keyframes 25 frames apart, it could look distracting.

[Patrick Mckenna]

Thanks for the reply.

Yeah, it’s definitely something in the export settings in Premiere. The AE file on the timeline in the Premiere looks fine but it is when it is exported from Premiere that has the flicker. Do you know what settings would be my best option??? The one I used (that causes the flicker at 1 second intervals) are Format: H.264 and Preset: Match Source – High Bitrate (it exports as .mp4). Any suggestion which might be a better export setting for this particular AE file??

[Kalleheikki Kannisto]

It depends largely on where you want to show the result. H.264 is a good format for many things, and you can adjust the Target Bitrate, Maximum Bitrate (higher) and Key Frame Distance (lower) settings to improve the quality for local viewing on a computer. But, if you’re gonna upload the video on YouTube for instance, you may end up having the same original problem show up once YouTube has processed the file no matter what format you use. Some people recommend variable bit rate, 2-pass encoding for the bitrate settings for best results on YouTube.

[Patrick Mckenna]

Hi Kalle,
Thanks for the responses. I’m a bit lost here. Am I wrong in saying that the issue I’m having is a problem that can’t be fixed?? I can’t grasp what the issue is. The noise and Venetian blinds effect that I added to the footage in After Effects seem to be very simple effects and the composition is nothing too complicated. I would expect that Premiere would be more than capable to export out a flawless video file of the comp, even if it were for YouTube.

[Kalleheikki Kannisto]

Premiere is perfectly capable of outputting your video at the highest quality, uncompressed. The problem comes from compressing the video with lossy compression for faster web viewing. You can create a perfect video for local viewing, but it is possible that the issues you’re experiencing with the default H.264 settings will reappear even if you upload an uncompressed video to YouTube, as YouTube will process it, recompressing any uploaded video to decrease file size. Premiere can output a perfect video, the question is what does YouTube do with it when you upload it.

A video with lots of detail that changes significantly from frame to frame, such as in the case of the video you describe, with noise and the venetian blinds effect, is challenging to compress.

The point being, YouTube does not display the same version of the video as you upload, it re-compresses it. Vimeo is a better option for high-quality video, but there are other limitations to it, such as how many HD videos you can upload with a free account.

I’m not saying the problem will occur. It may occur, for the above reasons.

[Patrick Mckenna]

Thanks for the reply Kalle.
It isn’t my intention to upload the file to YouTube. The clip in question is part of a short film that I’m working on. But my concern is that, hypothetically, I were to upload this composition to YouTube, will it mean that the H.264 codec that YouTube uses will cause this glitch and there’s nothing that can be done about it?

[Kalleheikki Kannisto]

I don’t know what settings YouTube uses to compress, but what I would do is take a small clip of the type you’re having trouble with, dial in the H.264 settings at your end until they look good, upload it on YouTube and see what happens. Maybe they won’t recompress if the settings (file format, file size vs video length) are already within their expected range.

Anyways, since that’s not your intended platform, you can simply increase the quality settings until the problem goes away. I would start by decreasing the distance between keyframes (H.264 keyframes, that is) to somewhere between 5 and 10.