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Finding subtle logos - tone on tone

Posted: Sat Apr 18, 2009 10:28 pm
by fmanji
Hi all,

First of all I have to say that I love using Comskip, it works great for most shows, and in most situations.

However, there are some situations where it can be quite challenging to find logo's.

In Canada, our logos tend to be quite small <5%, and quite often they change or are VERY subtle, in 24 there is a tone-on-tone logo, that can be difficult to detect using standard settings, I have found that making chages to two setting, seems to help a fair deal:

edge_level_threshold=x
edge_radius=y

My question is, is it better to decrease edge_level_threshold to find a subtle logo, or increase edge_radius, which method is preferred and would tend to give less false positives?

Also specifically for 24, I have found that setting validate_scenechange=0 help when thee is no logo to be found.

Hopefully someone is having the same issues with logos?

Re: Finding subtle logos - tone on tone

Posted: Mon Apr 20, 2009 8:21 am
by erik
For very faint logo's reducing edge_level_threshold makes most sense.
Increasing edge_radius increases the chance for finding a transition but not specific for faint logo's
There is however one golden rule: If it works, use it.
Setting validate_scenechange=0 works when you need the occasional scene change detected to have good commercial boundary detection. be aware that it may lead to false positives (show detected as commercial) but for 24 that seems not to become a problem.

Re: Finding subtle logos - tone on tone

Posted: Mon Apr 20, 2009 5:57 pm
by fmanji
For what it's worth, and if it helps others, here is what I have found.

Set edge_level_threshold=4
leave edge_radius alone (2)

Also for Canada I have found that it is just fine to set the logo max percentage of screen at 3%, it results in more accurate logo detection...