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  1. Member
    Join Date: Aug 2011
    Location: CA
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    What I mean is, there are of course filters for hue, brightness, saturation, etc. They work over the entire screen though. Is there software yet of affecting a specific area of the screen?
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  2. For a stationary area you can use an alpha mask. For something moving you might be able to build an alpha mask from the video itself using brightness, color, etc. For something more complex you'll need an NLE with tracking and a lot of patience.
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  3. The same area throughout? As an example of filtering just a specific area, is this the kind of thing you had in mind?

    A=Last
    B=A.Crop(184,0,-250,-228).Greyscale()
    Overlay(A,B,184,0)


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  4. Member
    Join Date: Aug 2011
    Location: CA
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    Yes, pretty much that.

    I assume that's AviSynth, with the overlay filter.

    I just need to figure out the coordinates. 0 is the very center right?
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  5. Member
    Join Date: Sep 2007
    Location: Canada
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    Originally Posted by smike View Post
    Yes, pretty much that.

    I assume that's AviSynth, with the overlay filter.

    I just need to figure out the coordinates. 0 is the very center right?
    The overlay syntax for coordinates is x=some number, y=some number

    x=0, y=0 would mean top left hand corner
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  6. I took the original color video (A) and cropped it by 184 from the left, nothing from the top, 250 pixels from the right and 224 pixels from the bottom. I then greyscaled that rectangle (turned the saturation to zero). To overlay the now black and white rectangle (B) over the original color video you need only the left and top values to designate the location.

    You can use any filters you like on any sized rectangle you create. You can also feather or blend the filtered part into the non-filtered main video.
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  7. just use the free NLE, AviUtl. Working in a GUI and doesn't need to guess around the coordinates.
    (v1.4 will be release soon on videohelp.com, for the time being, grab from my site:
    http://mavericktse.is-a-geek.com/wordpress/archives/1426)
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  8. Originally Posted by MaverickTse View Post
    just use the free NLE, AviUtl. Working in a GUI and doesn't need to guess around the coordinates.
    Look, I'm enjoying learning about AviUtl and plan on testing out your new logo remover filter when I begin my next project soon , but there's no need to denigrate a 'competitor'. Guess around? Please. There are a number of ways to crop in AviSynth that don't involve guessing. I didn't 'guess' anything but cropped as much as I wanted and did it the first time without guessing and retrying again and again. Come back and claim to be better when you have the full range of filters that AviSynth does. AviUtil can do a few things better and/or more easily than AviSynth; AviSynth can do many many things better and/or more easily than AviUtil. At least for the things I use AviSynth for (video 'restoration', mostly) there's no contest.
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  9. manono, i am not trying to saying anything bad for tools like avisynth. Yet, the OP did not state clearly what he want, so I will just offer another alternative.(as GUI)Make no mistake, i am not the author of aviutl, i just translated it and promote it
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  10. Using an any arbitrary shape instead of a rectangle:

    Code:
    # get an image to use as an alpha mask
    # blur it to soften edges
    circle=ImageSource("mask.png", start=0, end=23, fps=23.976).ConvertToYV12(matrix="PC.601").Blur(1.0).Blur(1.0).Blur(1.0)
    
    # get the main video
    ImageSource("Test.jpg", start=0, end=23, fps=23.976).ConvertToYV12()
    
    # make it all greyscale then discolor it
    # to eliminate manono's greyscale block
    # (you wouldn't normally do this to your video source)
    ColorYUV(cont_u=-256, cont_v=-256) # greyscale
    ColorYUV(off_u=-20, off_v=20) # to orange
    
    # overlay a greyscale version of the video onto the "original" image using the mask
    Overlay(last, GreyScale(last), mask=circle)
    Name:  greycircle.jpg
Views: 69
Size:  46.6 KB

    The mask was just a white circle on a black background. I created the mask image by importing one frame of the video into a paint program, drawing a white circle over the woman's face, then turning the rest of the image black.
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