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  • Rusty
    replied
    Thanks Timo,
    Originally posted by Timo View Post
    Median is not the Matrix-filter ( the one with the numbers )
    Both filters are usefull for to soften the image and/or remove noise ( especially 1-pixel-noise )

    By the way: i did a short explanation a few years ago for the matrix-filter ( but it is in german )

    http://www.mpeg-dvd.de/pdfs/matrix.pdf
    Google Translation (follow the magic footprints) in the PDF above! Pretty good.

    How does the matrix filter ...
    When matrix filter every single pixel of the video re-calculated. This
    happens in relation to the neighboring pixels. Each pixel that is not on the edge the video is therefore 8 neighboring pixels to influence the core pixels.
    I'm staying here at only example of the brightness, (Canopus in the matrix filter by selecting the "normalize checkbox), the operation is scheduled for Farbinhalt basically identical, but would more likely lead to confusion. To put it to further simplify, I am here only the values 1 (for black) and 0 (for
    white) dar. course, there are actually 255 values. The actual pixel is here
    black and has 3 black and 5 white neighboring pixels. The centerpiece of Pixels is his Value twice as high as the edge pixels.
    How is the new value now?
    The sum of all weighted Nachbarpixelhelligkeiten -> new target pixel brightness:
    0 × 0.1 1 × 0.1 × 0.1 0
    1 × 0.1 1 × 0.1 × 0.2 0
    0 × 0.1 0 × 0.1 × 0.1 1
    = 0.5
    Contrast slowdown
    Without action now would be the matrix filter with the following setting, since the Neighboring pixels with the value 0 in the filter is not changed.
    0 0 0
    0 1 0
    0 0 0
    In the case of our video content would look like this .........
    Would a matrix with the following filter settings, the effect of
    Contrast slowdown have:
    0 1 0
    1 1 1
    0 1 0
    Now would be the result with the following matrix filter of course, almost identical:
    1 0 1
    0 1 0
    1 0 1
    But the value of the algorithm is obviously something more complex than he simplifies is displayed. But I think of her understanding, it should be clear.
    The effect is the classic blur the edges are smoothed and Individual points adapt to the environment an.Durch adjust the values can now similar effects with different "levels" of smoothing achieve.
    0 7 0
    7 5 7
    0 7 0
    With negative values such as So here you could achieve An edge reinforcement:
    0 -2 0
    -2 1 -2
    0 -2 0
    I hope it was understandable :-)

    Leave a comment:


  • Timo
    replied
    Median is not the Matrix-filter ( the one with the numbers )
    Both filters are usefull for to soften the image and/or remove noise ( especially 1-pixel-noise )

    By the way: i did a short explanation a few years ago for the matrix-filter ( but it is in german )

    http://www.mpeg-dvd.de/pdfs/matrix.pdf

    Leave a comment:


  • GrassValley_BH
    replied
    I don't have a full grasp of what it does either, but it's supposed to remove some grainy-ness without impacting the entire frame like a full blur would.

    Leave a comment:


  • Philip
    replied
    Originally posted by GrassValley_BH View Post
    Most simple smoothing filters soften (blur) the video - that's how they smooth. You might wan to try the Median filter.
    Can the Median filter smooth out grain? I still have no clue what the Median filter does. One time I read a small explanation of it but it makes no sense to me. Is there a good explanation of the filter and what all those numbers in the little boxes mean. I never use it for anything cause I haven't a clue what it does.

    Leave a comment:


  • GrassValley_BH
    replied
    Most simple smoothing filters soften (blur) the video - that's how they smooth. You might wan to try the Median filter.

    Keyframing allows you to change parameters over time. For example, you might tint from blue to red to normal using Color Balance.

    Leave a comment:


  • Feralhog
    started a topic Video Filter Application Question. . .

    Video Filter Application Question. . .

    First I'd like to thank this forum and it's members for all your help. I'm amazed at the things I've learned by just reading this site and asking questions.

    I'm editing action video that was recorded by with high resolution security cameras (540 lines). The lighting in the building isn't the best in the world and the cameras are mounted 28 feet high and roughly 40 feet from the action.

    I'm not sure what the technical term is, I'm combining the two cameras into one m2p video file.

    I'm pan and zooming the video with 3D Picture in Picture and I'm having trouble finding the right filtering combination.

    Right now I'm using the color wheel set at H-20.82 deg. S+27. Bright 30 Contrast 10. The safe Color Box is checked, the Enable Key Frame is not Checked. (Not sure what enable key frame does?)

    Blend Filter with Sharpness and Loop slide. Sharpness set at 55, Loop Slide Horizontal Slide Speed 39, the initial position is 0. Vertical Slide Speed is 52, initial position is 73. Key Frame is checked and Polyline is checked.

    My video is grainy and there seems to be a lot of flickering. When I add one of the smooth filters, the flicker and grain go away but the picture is blurry.
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