AutoCropper plugin (3 Viewers)

[ziphnor]

A first tentative version has been added to SVN and should be available with the next snapshot. Manual mode (where you press a key to crop) should be pretty reliable(but dont shoot me if you encounter a bug!) while Auto mode is more experimental and (currently) very resource demanding.

 

[eloo]

milestone

Hi, congrats, I have been following this thread for months and I look forward to testing this feature. As a danish user, this is much appreciated!

 

[ziphnor]

Looking forward to have someone testing it

You will find the plugin under Plugins->Process Plugins. The configuration screen has a link to a wiki page explaining the necessary setup steps (ie, you need to assign some keys to some actions to get it working).

If you try out the auto mode, please recall that its experimental, but that being said, please report your experience.

 

[risu]

I'm using purevision codecs and using manual autocrop ends somewhat weird aspect ratios if source video isn't letterboxed 16:9. Even when it is, I always have to use stretch zoom mode to fill up my widescreen. As it requires stretch zoom (probably only with widescreen resolutions) it would be good if it changed the zoom mode automatically when cropping. Even an option in plugins to do so would be good. Or if possible then set the anamorfic flag so codec adapts?

On rare ocasions they send someting like 2:35:1 in letterbox. So this leads to that I'd also like to see this plugin to have a limit for distording of the aspect ratio, say limiting the autocrop to stop when zoomed over 10% of aspect ratio of the display. I'd rather have little bars on side/top/bottom than watch too distorded image. Any other than that, seems to work just fine. As for manual autocrop on letterboxed 16:9 it works as it should (if we count strecth-issue out). Good work ziphnor =).

 

[maysider]

nice, but

really needed feature, but I do not want to stretch cropped picture, then it is useless for me
And would be nice, if there is possibility to define sensitivity (perhaps for every TV channel (because of the different logos)

 

[ziphnor]

ASPECT CORRECTNESS:
I must admit that the aspect ratios (zoom modes) dont act as i thought they would on cropped material(thats the problem with testing the cropper on a 4:3 PC monitor . I do plan to look into this to make it possible to get aspect correct cropping.

As a quick fix, i will probably add an option to restrict the crop to 16:9. The plan was to include this in the first release, but i started wondering what would happen if something weird like anamorphic letterboxed material showed

Im open to ideas on the best way to handle these issues.

ABOUT LOGOS:
If you have problems with logos, then you need to adjust the top(or bottom) start/end scan parameters (and yes i know the help doesnt explain this, it will soon). The cropper will include EVERYTHING it scans and finds not to be black bars(ie also logos). The default settings exclude all logos used on danish TV channels by not scanning the place on the screen they occupy. For example, if the logo is in the top right corner and is included with the current settings, then decrease the Top Scan End parameter, to avoid scanning the part of the frame containing the logo. The top scan start/end parameters tell the cropper how much of each line in the image to scan, for example if you set it to 0% - 50% it will in the search for the top part of the image scan the left half of the frame.

 

[Seidelin]

Great work

I just installed the autocropper, and I love it!
The only issue I can see is, that it appears that the cropper doesn't adjust the width of the picture, resulting in stretched pictures when subtitles are placed low in the picture.
Haven't tried the automatic cropping yet, but the manual one is good enough for me.

To correct the aspect ratio correctly, the width of the picture should be modified by this formula:
relative Width=0.75/CroppedHeight
If relative width is larger than 1, then CroppedHeight should be adjusted up to minimal sensible crop height which is 0.75.

By CroppedHeight I mean the number of lines shown divided by number of lines in full frame. Relative Width is a number less or equal to 1. If relative width is 0.9 then there should be 5% black frame on both sides of cropped picture.

Good work Ziphnor. Hope you can use my input.
Seidelin

 

[ziphnor]

Update on Aspect Correct Cropping:
Well, i found out WHY the 'Normal' zoom mode doesnt give aspect correct cropping as i was hoping. The source(ie bit of original frame to use) and target rectangle(ie part of screen to scale to) are computed first without looking at the crop settings and then the cropping is applied to the source rectangle only.

This can either be solved by making the zoom modes aware of the crop settings, or by adjusting the target rectangle to maintain correspondence with the new dimensions of the source rectangle. I think im going to go with the latter option.

I could also implement the whole thing as a new zoom mode, but basically i think that is mixing to different things. One thing is removing the black bars, and another is deciding how you want to show the result.

Im very busy with family stuff in this holiday though, so dont expect changes this year [For the temporally challenged, not that there is very little left of this year ]

 

[illStyle]

A new zoom mode would be a very good idea! Something like "auto" or "intelligent zoom" or something like that.

Simon

 

[ziphnor]

A new zoom mode would be a very good idea! Something like "auto" or "intelligent zoom" or something like that.

I dont really like that idea. As i said, i believe its mixing the cropping functionality with the aspect ratio/zoom mode functionality.

I would rather make it so that 'Normal' + autocropper gives aspect correct cropping while "Stretch" + autocropper crops and then stretches to fit.

The problem is that if you have broadcast with only a single line(or part of a single line) of subs in the black bar, then some people will want to stretch it, even though it wont be aspect correct, while others wont, meaning i would have to add two zoom modes, and both of them would have to be toggeable between auto and manual which would be confusing.

Im open to discussion though, i dont want to implement this one way and then change it, so please post arguments for the different approaches.