This is caused when you converted interlaced footage to Progressive, without deinterlacing it. That artifacting is “burned in.” Meaning that it’s baked into the clip…you can’t deinterlace it now. The only way to get rid of it is to convert it again, this time deinterlacing it when you convert, or before you convert. If you have this in your timeline and you export to YouTube..then you need to deinterlace it on your timeline, THEN export.
Shane
Little Frog Post
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