unwanted blur at frame edge

[Arne_LGN]

I applied (Gaussian) blur to a png-file that shows two white squares. The white surfaces (before being blurred) run until the top edge of the 'film' frame, but Ae blurs the top edge of the white squares as if there is some space between the top edge of the squares and the top edge of the film frame. Any way to avoid this to happen? I could work with masks, but it gets messy at the top corners of the white squares (they move around, it's a png-sequence).

[Rick Gerard · Accepted solution]

This problem is a lot easier to diagnose if you include a screenshot with the modified properties of the layers giving you problems revealed. Just select the layer and press the U key twice. I'm guessing that the edge of the comp frame matches the edge of the png file. If that is the case then turning on Repeat Edge Pixels would simply remove the blur because there is no detail in the white squares. You could check out how Repeat Edge Pixels works by loading a photograph into the timeline, moving it to the edge, applying a fair amount of blur and then cycling the option on and off. From all indications the effect is working as designed.

If you can't solve the problem by scaling the images vertically or there is something else going on in your composition let us know and provide a screenshot that tells us something about what you are doing in the comp. Otherwise you'll have to replace these white squares with ones that extend beyond the edge of the frame. I would just use shape layers.

[Dave_LaRonde]

Looks like you added the blur to an adjustment layer.  Don't.

[Arne_LGN]

Hi David,

I didn't use any adjustment layer, I applied the blur effect directly to the png-sequence.

[Rick Gerard]

If the png sequence is the same size as the comp frame you have two . If the image sequence has a transparent background then you have to add a black solid to the bottom of the timeline, pre-compose, then add your blur to the pre-comp and turn on repeat edge pixels. This will sharpen up the edges but blur the detail. If the image sequence has a solid background then turning on Repeat edge pixels will fix the problem. Like I said before, a screenshot showing exactly what's going on in the project and with the footage would help us nail down a solution.

[Arne_LGN]

Hi Rick, turning on 'repeat edge pixels' worked fine. Thanks!