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  1. I have a Blu-Ray that is very soft/blurry looking in 1080p.

    I decided to try downscaling it to 720p with Spline36Resize and its still pretty soft.

    I also tried something called DebilinearM for downscaling. I made sure I was using the correct native resolution. Even spline36 with a sharpener did not get this crisp looking. Overall Debilinear did an amazing job at sharpening it, but it has a side effect I really really hate. For some reason it looks like it is adding grain or artifacts all over the image and when zoomed in I think it looks terrible.

    I think Debilinear uses dithering or something that is adding this grain or artifacts. I could be wrong but I was wondering if anyone can help me get this sharper without the grain or artifacts being so obvious. Is there a way to turn off the dithering if that's what its doing?


    Here are some screenshots.

    (Spline36)
    https://i.imgur.com/GPPf9Dd.png

    (Debilinear)
    https://i.imgur.com/8WCc6cn.png

    (Flip Through Comparison)
    http://screenshotcomparison.com/comparison/116393
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  2. It looks to me like Debilinear is simply accentuating noise that's already in the image. Isn't that what you expect from a sharpener?
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  3. Originally Posted by jagabo View Post
    It looks to me like Debilinear is simply accentuating noise that's already in the image. Isn't that what you expect from a sharpener?
    Yeah, when the strength is set too high I expect that usually and try to not make it too strong.

    The thing is, I can use spline36resize and LimitedSharpenFaster(ss_x=1.00, ss_y=1.00, strength=20, overshoot=0, undershoot=0, soft=0, edgemode=0) it looks almost as sharp, but has barely any of the added in artifacts/grain that debilinearm makes extremely obvious. Because of that, so far I have gone with just not using debilinearm even though I like how it sharpens.

    I guess the dithering is something you cant turn off with debilinear? I thought about playing with the .avsi file and manually making changes, but I would probably break it.
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  4. Originally Posted by killerteengohan View Post
    I guess the dithering is something you cant turn off with debilinear?
    The docs don't show any controls for it.

    Originally Posted by killerteengohan View Post
    I thought about playing with the .avsi file and manually making changes
    debilinear is a dll file, not an AVSI script.
    Last edited by jagabo; 8th Jul 2018 at 22:55.
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  5. Originally Posted by jagabo View Post
    Originally Posted by killerteengohan View Post
    I guess the dithering is something you cant turn off with debilinear?
    The docs don't show any controls for it.

    Originally Posted by killerteengohan View Post
    I thought about playing with the .avsi file and manually making changes
    debilinear is a dll file, not an AVSI script.

    DebilinearM however is not just a DLL file. As you can see it mentions dither in it and that's where I got the idea that it's dithering causing this and trying to not use dithering if possible. Seeing as how it has masking in it, I thought it might be possible so figured Id ask around here for ideas.


    /* DebilinearM v1.3.1

    DebilinearM is a wrapper function for the Debilinear and Debicubic plugins that masks parts of the frame that aren't upscaled,
    such as text overlays, and uses a regular resize kernel to downscale those areas. It works by downscaling the input
    clip to the target resolution with Debilinear or Debicubic, upscaling it again, comparing it to the original clip,
    and masking pixels that have a difference greater than the specified threshold.

    ##### Requirements #####

    Plugins:
    Debicubic
    Debilinear
    Dither
    MaskTools2

    Scripts:
    ResizeX

    Color formats:
    YV12
    */

    function DebilinearM(clip input, int target_width, int target_height, int "thr", int "expand", int "inflate",
    \ string "kernel", int "taps", float "a1", float "a2", bool "cubic", float "b", float "c",
    \ bool "chroma", bool "lsb_inout", int "showmask") {

    # Default settings and other variable assignment
    thr = Default(thr, 10)
    expand = Default(expand, 1)
    inflate = Default(inflate, 2)
    kernel = Default(kernel, "Spline36")
    cubic = Default(cubic, false)
    chroma = Default(chroma, true)
    lsb_inout = Default(lsb_inout, false)
    showmask = Default(showmask, 0)

    Assert(target_width > 0, "DebilinearM: target width must be greater than 0")
    Assert(target_height > 0, "DebilinearM: target height must be greater than 0")
    Assert(thr >= 0 && thr <= 255, "DebilinearM: thr must be in the range 0 to 255")
    Assert(showmask > -1 && showmask < 3, "DebilinearM: showmask must be 0, 1, or 2")

    w = input.Width()
    h = lsb_inout ? input.Height()/2 : input.Height()

    uvint = chroma ? 3
    \ : 1

    # Resizing
    input_8bit = lsb_inout ? input.DitherPost(mode=-1) : input

    cubic ?
    \ Eval("""
    dbi = chroma ? input.Debicubic(target_width,target_height, b=b, c=c, lsb_inout=lsb_inout)
    \ : input.DebicubicY(target_width,target_height, b=b, c=c, lsb_inout=lsb_inout)
    dbi_8bit = chroma ? input_8bit.Debicubic(target_width,target_height, b=b, c=c)
    \ : input_8bit.DebicubicY(target_width,target_height, b=b, c=c)
    dbi2 = lsb_inout ? dbi_8bit.ResizeX(w,h, kernel="Bicubic", a1=b, a2=c, chroma=chroma)
    \ : dbi.ResizeX(w,h, kernel="Bicubic", a1=b, a2=c, chroma=chroma)
    """)
    \ : Eval("""
    dbi = chroma ? input.Debilinear(target_width,target_height, lsb_inout=lsb_inout)
    \ : input.DebilinearY(target_width,target_height, lsb_inout=lsb_inout)
    dbi_8bit = chroma ? input_8bit.Debilinear(target_width,target_height)
    \ : input_8bit.DebilinearY(target_width,target_height)
    dbi2 = lsb_inout ? dbi_8bit.ResizeX(w,h, kernel="Bilinear", chroma=chroma)
    \ : dbi.ResizeX(w,h, kernel="Bilinear", chroma=chroma)
    """)

    rs = input.ResizeX(target_width,target_height, kernel=kernel, taps=taps, a1=a1, a2=a2, chroma=chroma, lsb_in=lsb_inout, lsb=lsb_inout)

    # Masking
    diffmask = mt_lutxy(input_8bit,dbi2, "x y - abs", U=uvint, V=uvint).mt_binarize(threshold=thr, U=uvint, V=uvint)
    diffmask = showmask == 2 ? diffmask.DebilinearM_expand(expand=expand, U=uvint, V=uvint)
    \ .DebilinearM_inflate(inflate=inflate, U=uvint, V=uvint)
    \ : diffmask.ResizeX(target_width,target_height, kernel="Bilinear", chroma=chroma)
    \ .mt_binarize(threshold=3, U=uvint, V=uvint)
    \ .DebilinearM_expand(expand=expand, U=uvint, V=uvint)
    \ .DebilinearM_inflate(inflate=inflate, U=uvint, V=uvint)

    merged = lsb_inout ? Dither_merge16_8(dbi,rs,diffmask, u=uvint, v=uvint)
    \ : mt_merge(dbi,rs,diffmask, U=uvint, V=uvint)

    return showmask > 0 ? diffmask
    \ : merged
    }

    # DebicubicM alias
    function DebicubicM(clip input, int target_width, int target_height, int "thr", int "expand", int "inflate",
    \ string "kernel", int "taps", float "a1", float "a2", float "b", float "c",
    \ bool "chroma", bool "lsb_inout", int "showmask") {

    return DebilinearM(input,target_width,target_height,thr,e xpand,inflate,kernel,taps,a1,a2,true,b,c,chroma,ls b_inout,showmask)
    }


    # Helper functions
    function DebilinearM_expand(clip input, int "expand", int "U", int "V") {
    return expand > 0 ? DebilinearM_expand(input.mt_expand(mode="both", U=U, V=V), expand-1)
    \ : input
    }

    function DebilinearM_inflate(clip input, int "inflate", int "U", int "V") {
    return inflate > 0 ? DebilinearM_inflate(input.mt_inflate(U=U, V=V), inflate-1)
    \ : input
    }

    I got the idea to use this from here. Perhaps its information can help some? There are some things they were showing that I didn't quite fully get since I have no Vapoursynth experience.

    https://kageru.moe/blog/article/resolutions/#c_basics
    Last edited by killerteengohan; 9th Jul 2018 at 13:36.
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  6. Is it true that spline36resize is not meant for mod16 video?? I read that when working on mod16 video that spline36 creates more artifacts in the video.
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  7. Member
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    Originally Posted by killerteengohan View Post
    Is it true that spline36resize is not meant for mod16 video?? I read that when working on mod16 video that spline36 creates more artifacts in the video.
    Interesting. Where did you read that?
    Interesting, because most standard video DVD/BD retail format dimensions from 352 to 1920 are mod16, except for 1080 which is mod8.
    - My sister Ann's brother
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  8. You know that sharpness don't exist, it's just a trick, a perception, to fool your brain and contaminate the image with noise.

    Take this for example, witch one is sharper?

    If you choose the one in the right, it just has more white noise to the edges, here is the image differential to prove it.

    Is rather better to leave the sharpness of the video intact and adjust the sharpness on your TV instead. Some TV's like to push sharpness way too high and when you play a video with sharpness applied to it, it looks much worse.
    Just to let you know, don't go crazy with it.

    More info:
    https://www.cambridgeincolour.com/tutorials/image-sharpening.htm
    https://www.cambridgeincolour.com/tutorials/unsharp-mask.htm
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  9. Originally Posted by amaipaipai View Post
    You know that sharpness don't exist
    Sharpness does exist. Which is sharper?

    Click image for larger version

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  10. Originally Posted by jagabo View Post
    Sharpness does exist. Which is sharper?
    Which one is darker, A or B?
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  11. Originally Posted by amaipaipai View Post
    You know that sharpness don't exist, it's just a trick, a perception, to fool your brain and contaminate the image with noise.
    In some cases this is true, but if it is only a trick, it is one heck of a trick.

    I transfer film, and sharpening makes a HUGE difference in the ability to see details. Here's the proof that I posted years ago in the following doom9.org thread:

    The power of Avisynth: restoring old 8mm films

    I used the crude early version of that film restoration script, and here is the "before/after" I created and posted in that thread:



    You are welcome to state that the massive improvement in the ability to resolve the vertical railings on that porch is just perception, but I think that opinion would be in the minority. Also, while you are absolutely correct that image noise can create a perception of more sharpness when that noise is present (or added) in moving images, noise had nothing to do with this result.

    Finally, I did this work myself, so I can guarantee that this result is real, and was done with the script posted earlier in that doom9 thread by "VideoFred."

    P.S. Here's a link to a "before/after" video showing all aspects of the film restoration I've been doing. This thread is about sharpening, so pay attention to the first few examples, especially the one taken of the sign:

    https://www.youtube.com/watch?v=tBAHzO7rJS0
    Last edited by johnmeyer; 11th Jul 2018 at 18:04. Reason: added video link
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  12. Member Cornucopia's Avatar
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    Yes, evidence of exceptions to the rule do not necessarily completely disprove the rule.

    Scott
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  13. Originally Posted by Cornucopia View Post
    Yes, evidence of exceptions to the rule do not necessarily completely disprove the rule.

    Scott
    While I'll admit to NOT being a fan of sharpening for video, what it does with film is FM ("M" stands for magic and "F" stands for, well, you know ...).
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  14. Originally Posted by johnmeyer View Post
    In some cases this is true, but if it is only a trick, it is one heck of a trick.
    It is.
    Doesn't matter how hard I try to convince you that in the above picture A and B spot has the EXACT same color, you won't agree with me, don't matter what I say. To do a sharpness effect you sample it, invert it, extract the differential of both and apply it, this is sharpness in a nutshell. Here another example of it:


    If you take a gray background, draw a light gray line and zoom in to the pixel level, you can't make the light gray line any sharper that already is, this is not different from video, photo, etc.


    Sharpening tools may increase acutance but it also decrease the signal-to-noise ratio. For restoration propose, and I'm not a specialist on the matter, you don't want to add more noise to something that already has a lot. I'm sure that for general propose, there is no problem to add sharpen effects to your material or if you use it at your home, but in relation to restoration I personally, would never use any sharpness tools to restore anything.

    Looking at your samples, it looks great, it really do!
    But this stuff it's like when you learn how to ride a bike, even if you want it to, you can't unlearn it. Aside the looks, I see that the noise has increased and around the dark borders like around the stairs, I can spot white lines and dots around it, if you pay attention, this white line is on the top of everything that is black.

    This one bellow it's the one I did, I don't apply sharpness to anything, download it and look at your computer.


    For restoration I love the job they did with Richard III:
    https://www.youtube.com/watch?v=mN49grFTKxY

    Restoration is an art, I see that restoration and shapness don't go along together.
    https://www.youtube.com/watch?v=3TEgrdAlofk
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  15. Member Cornucopia's Avatar
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    Adding sharpness usually/often is the last step in most restoration processes. It is often warranted, if done within reason.

    Your talk about acutance should be based on receptor scanning limitations. A "perfectly" sharp border transition is one that goes from dark to light (or vice-versa) instantaeously (like a square wave). But neither our eyes nor our photochemical or electronic sensors can scan & react instantaneously. It's more like a sine wave.
    So in order to compensate for that subjective loss of sharpness, wave overshoot aka edge enhancement is done, to subjectively restore the sense of sharpness.

    But, that shouldn't discount true differences in sharpness, because there are some transitions that actually ARE sine-wave-like, and square-wave transitions in comparison ARE truly sharper AND truly better SNR than those.
    Plus, one should never conflate sharpness (or more accurately, acutance) with contrast. They are inter-related, but refer to different characteristics. Contrast refers to the dynamic range (whether global or local), while sharpness & acutance refer to the edge slope and/or overshoot. Yes, higher contrast steepens the slope, thus giving the perception of greater sharpness, and oversharpened edges (with overshoot) have by their nature greater contrast. But they can be manipulated somewhat independently. A squarewaved dark gray to light gray is considered less sharp than a squarewaved black to white, specifically because of the greater contrast, even though both would be considered perfectly sharp.
    Grain or noise (or dither) is another semi-independent factor. You are wrong when you say that noise is antithetical to restoration (both visually & audibly). It just needs to be controlled, applied judiciously.

    @johnmeyer, I was actually somewhat agreeing with you back there. But part of that miracle could be due to you just getting closer to that squarewave slope (because of film's inherently higher potential innate resolution in those days), not necessarily because of OVERsharpening (though your example did exhibit some).


    (Btw, that lady karaoke restoration example would be less aggravating in its proper AR comparison, plus it was clear you may not have increased accutance but you did play with contrast)

    Scott
    Last edited by Cornucopia; 12th Jul 2018 at 00:47.
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  16. I quote a science study abstract from the Society of Photo-Optical Instrumentation Engineers (SPIE)
    https://www.spiedigitallibrary.org/conference-proceedings-of-spie/7240/1/Analysis-of-s...78.short?SSO=1
    Originally Posted by SPIE
    Motivated by the reported increase in sharpness by image noise, we investigated how noise affects sharpness perception. We first used natural images of tree bark with different amounts of noise to see whether noise enhances sharpness. Although the result showed sharpness decreased as noise amount increased, some observers seemed to perceive more sharpness with increasing noise, while the others did not. We next used 1D and 2D uni-frequency patterns as stimuli in an attempt to reduce such variability in the judgment. The result showed, for higher frequency stimuli, sharpness decreased as the noise amount increased, while sharpness of the lower frequency stimuli increased at a certain noise level. From this result, we thought image noise might reduce sharpness at edges, but be able to improve sharpness of lower frequency component or texture in image. To prove this prediction, we experimented again with the natural image used in the first experiment. Stimuli were made by applying noise separately to edge or to texture part of the image. The result showed noise, when added to edge region, only decreased sharpness, whereas when added to texture, could improve sharpness. We think it is the interaction between noise and texture that sharpens image.
    I was the one that did not.
    You are discussing about a subjective matter, I'm not. Again, take that A and B spot, witch one is darker?
    It doesn't matter how your biological or electronic receptor understand that image, it would be wrong both ways, even if you print it out and overlay the papers on top of each other your brain still would not understand.

    Don't get me wrong, I'm not against the use of the sharpness at all.
    I just believe that there's not a place for it in restoration. It make no sense - to me - to add noise, decrease the signal-to-noise ratio in something that you want to restore back to it's pristine condition, sorry, that math don't add up to me.

    This is the overshot you was talking about:

    Even if you control it and add a small amount of it, you are still add noise to he picture and is impossible to reach a ideal condition, it wont happen and if you do it, something has to give. This is the price you pay for adding a sharpness effect just for acutance, you contaminate your material just for looks knowing that it's doing a damage to it.

    To my understanding, and respecting yours, this is the same if you take perfect peace of music, increase the noise floor a little bit because you perceive that doing that, it gives a warmer feeling to it. Or if you take low quality mp3 file, boost the high frequency, people will perceive the sound more crisp at the high notes, hence it sound better! And we know that this is not the case, we can't create a perception of more resolution with sharpness without a real increase in resolution, we can't create something out of nothing.

    Again, all this talk is related to restoration. If you like to do this to your photos and videos, keep doing it, just don't go crazy about it.
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  17. Member Cornucopia's Avatar
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    What you're forgetting about in your example is that the "ideal" is often arrived at (or very closely approached) in the real world by averaging an overshoot/undershoot WITH a weak sine. They're much more useful than you give them credit for. Including as pertains to restoration.

    Also, adding dither (a form of noise) is a very important and well-documented way of improving the (or more rightly, not losing the original) dynamic range by randomizing the quantizer so it doesn't create distortion (often in audio) and/or banding (often in video).

    As I mentioned previously, sharpening is almost ALWAYS best done as one of the very last steps in the process (and where, if you intend to work on a project further, you would want to save a copy that was not sharpened yet). You keep making it seem as if people are routinely sharpening as one of their first elements in their chain. That is indicative of not understanding what's going on in the process. There are exceptions (as witnessed by johnmeyer), and those usually happen right at the capture stage.

    Scott
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  18. Originally Posted by Cornucopia View Post
    ... As I mentioned previously, sharpening is almost ALWAYS best done as one of the very last steps in the process (and where, if you intend to work on a project further, you would want to save a copy that was not sharpened yet). You keep making it seem as if people are routinely sharpening as one of their first elements in their chain. That is indicative of not understanding what's going on in the process. There are exceptions (as witnessed by johnmeyer), and those usually happen right at the capture stage.

    Scott
    Just to be clear, the sharpening in my current film restoration script is done very near the end. I heavily modified the original script used to produce the results in that doom9.org link I provided above to eliminate the problem of having five different sharpening steps scattered throughout the script. Some of them were done early in the process, and the artifacts got magnified later in the script. In fact, if you want to see what violence sharpening can do, click on the link in my previous post and look at all the other results I posted, all of which are awful. Here is one of the pictures from that thread to show you how terrible unfettered sharpening can be:



    However, once I eliminated about 90% of the sharpening, and placed the sharpening at the very end, as Scott suggested, my heavily modified version of the OP's script was able to consistently "reveal" detail that was not clear in the original, but with very few obnoxious artifacts. That before/after video I linked to above shows the results. While a few of the clips in that video do exhibit a small amount of the classic sharpening white halo, if you look carefully at the original, some of those were already in the original, due to backlighting and other natural reasons why halos sometimes exist in nature. Also, there is none of the bloated grain that you see in the example above.

    Finally, it seems that as this thread has been pulled off topic, that some are now arguing about how many angels fit on the head of the pin, i.e., really esoteric stuff that doesn't have one bit of practical value, certainly not for the OP. It is sometimes fun to show off one's knowledge and training, but what's the point?
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  19. I believe you are still trying to win an argument by your acutance, again, if you are doing a production or post-production and want to apply a sharpness just for looks, do it.
    My regards is with restoration.

    This back and forth are going no where, I've shown enough proof that sharpness doesn't exist, it's a trick to fool your mind, the same with the A and B experiment, it doesn't matter how you take it, it is what it is. My area is signal processing not video/photo/audio restoration, but even then, there is an understanding that you don't add noise and decrease the signal-to-noise ratio you want to restore, we are looking for the best and clear signal possible and you can't achieve this with a sharpness effect because it contaminate the material with noise.

    What people are looking in to, is to restore image definition with shapness, that is impossible!

    When you want to restore something, you want to get rid of the noise and not add more.

    I follow the nyquist–shannon sampling theorem that say that the sampling frequency must be greater than twice the maximum frequency one wishes to reproduce, to achieve that, if I want to work at some material for 2k, I scan it in 4k and so on.

    The concept used are well known on the market, without the use or need for sharpness.
    https://www.image-engineering.de/library/technotes/749-the-concept-of-noise-reduction
    https://vimeo.com/84135659
    Last edited by amaipaipai; 13th Jul 2018 at 03:27. Reason: Added extra link
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    The discussion may be perceived to be a little off topic but a good discussion and interesting articles on the underlying theories and methods. Thank you. John, your restoration scripts are impressive.
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  21. Yes!
    John scripts are amazing!
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  22. Originally Posted by wim72 View Post
    The discussion may be perceived to be a little off topic but a good discussion and interesting articles on the underlying theories and methods. Thank you. John, your restoration scripts are impressive.
    Thanks! I have tried very hard to do things that are helpful and practical. Since I am an engineer by training, and not a scientist, I'll admit to having a tough time finding anything useful (i.e., something that can be put into practice) in all these posts about sharpening. How can I use any of this information to make my film and video look better?

    By contrast, VideoFred, over in doom9.org, is a really practical guy who built a very interesting film transfer system, entirely of his own design and then, using dozens of AVISynth functions, created a script has helped lots of people improve their film transfers.

    If you haven't seen the results if his work, click on the following link and play his three minute video. It is pretty astonishing to me, even after all this time (this was posted eight years ago) and even after all the restoration work I've done myself. He is still the master, and I am a humble pupil. Despite all the negatives about sharpening, based on theory and not practice, I ask this simple question: would you rather watch the "before" or the "after" in Fred's examples?

    Here's the link:

    Improved Avisynth 8mm film restoring script

    https://vimeo.com/13173031

    The fruit basket still amazes me.
    Last edited by johnmeyer; 13th Jul 2018 at 17:07. Reason: typos
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  23. Originally Posted by johnmeyer View Post
    Since I am an engineer by training, and not a scientist, I'll admit to having a tough time finding anything useful (i.e., something that can be put into practice) in all these posts about sharpening. How can I use any of this information to make my film and video look better?

    By contrast, VideoFred, over in doom9.org, is a really practical guy who built a very interesting film transfer system, entirely of his own design and then, using dozens of AVISynth functions, created a script has helped lots of people improve their film transfers.
    You know that I'm not a big fan of people flashing titles as arguments, I'm sure the good VideoFred agree with me because I never saw him doing it.

    Any way, if you read between the lines, there is no practical way to do this.
    You use VideoFred script, that is not practical, someone had to sit down, use his own time, experience and knowledge to craft the script peace by peace before it got to a final version, FOR FREE.

    If you read between the lines all the knowledge are laid down for anyone to see, with samples, with links, with data with the example of the nyquist–shannon sampling theorem, with the videos I've shared showing how the top professionals on the market do it.

    Take the example of that karaoke lady, I use QTGMC to deinterlace it, have you saw the size and complexity of that script?
    The load and work is so heavy that it took 6 days, non-stop, to denterlace 2 hrs material, not because my computer can't handle DV source, but because I've used a Blackmagic hardware to capture that in 4k resolution, so I could have a decent 2k material to work with (nyquist–shannon sampling theorem). That's not practical at all for a regular people that are just looking in to a way to convert a VHS to DVD.

    That CD back cover for example, it took 1.5 hours just to scan it using a HP Scanjet G4050 with a professional license of VueScan and there's no Photoshop plug-in or whatever image software to do that with a single click, or a magic wand, that work was done in Gimp by the way. As you can see, it's not practical, at all.

    There's no one solution fits all scenario.

    The process to achieve that was also told already, to sample the material, invert, boost the sharpness to increase noise, mask it and extract it. This is well know for years, but is not practical! You can look at this documents that is not new.
    https://pdfs.semanticscholar.org/9767/d662310dd07f5c4740794fdbaa731fc1ed70.pdf
    https://www.researchgate.net/profile/Bvignesh_Waran/post/How_to_do_local_contrast_enha...s-07-00597.pdf

    Can this be translated to a Avisynth script?
    Sure it can, a person will have to take his time, knowledge to craft something like the good old VideoFred did. I've given my share of knowledge to point whoever would do this to the right direction. A few months back I was trying to learn avisynth scripting to do some of this, but I gave up.
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  24. Originally Posted by amaipaipai View Post
    Originally Posted by johnmeyer View Post
    Since I am an engineer by training, and not a scientist, I'll admit to having a tough time finding anything useful (i.e., something that can be put into practice) in all these posts about sharpening. How can I use any of this information to make my film and video look better?

    By contrast, VideoFred, over in doom9.org, is a really practical guy who built a very interesting film transfer system, entirely of his own design and then, using dozens of AVISynth functions, created a script has helped lots of people improve their film transfers.
    You know that I'm not a big fan of people flashing titles as arguments, I'm sure the good VideoFred agree with me because I never saw him doing it ...
    Given your post just a few days ago here (everyone is encouraged to click on this link):

    "I was a former Sony Engineer in Japan ..."

    that statement is actually quite funny. As for my statement, I was merely trying to differentiate between a scientist, who tries to discover how the world works, and an engineer, who takes the science and tries to actually build something. Scientists research; engineers build.

    The rest of your post makes no sense to me, which I'm sure you will tell me is because I'm too dumb to understand. Regardless, I've said what I needed to say, and made an attempt to help the OP which, after all, is what this is supposed to be about. Feel free to continue, on your own, as I expect you will.
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  25. Originally Posted by johnmeyer View Post
    Given your post just a few days ago here (everyone is encouraged to click on this link):

    "I was a former Sony Engineer in Japan ..."

    that statement is actually quite funny. As for my statement, I was merely trying to differentiate between a scientist, who tries to discover how the world works, and an engineer, who takes the science and tries to actually build something. Scientists research; engineers build.
    Oh, I remember you.
    Yes, I don't like smart ass, garbage people like you that try to talk people down because you think you are better than others just because you have a EE degree, that you don't have, and try to shove it at peoples faces, just because garbage people like you think are better that others. I didn't told you that I'll get your ignorance and beat your ass with it?

    I'll refresh your memory:
    https://forum.videohelp.com/threads/387943-No-display-nor-sound-while-playing-the-VHS-...er#post2511275

    Did you saw me been rude to you after that event?
    https://forum.videohelp.com/threads/388166-Panasonic-VCR-issues-what-could-it-be

    Didn't you learn your lesson?
    Are you still want to be a jerk?

    You say you have a Electronic Engineer Degree and can't understand basic math, how come? Bitch?
    That's why it makes no sense to you, you are the first "Engineer" that can't read math and proves how you are full of shit.

    I also invite people to look at all my posts, there's no post you can find me been rude to any one in this forum but to idiots like you and the other guy that uses fallacy as arguments.
    Last edited by amaipaipai; 14th Jul 2018 at 00:38.
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  26. Member Cornucopia's Avatar
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    I find it ironic that you do all this boasting, but don't understand that you CANNOT get any more resolution out of DV footage, whether you transfer as DV, or convert to analog and capture with a 4k card, regardless of your pronouncement of Nyquist theorem backing.

    Btw, that NR paper is interesting and has some good ideas, but it is quite flawed in its assumption of the breakdown of noise vs signal in its reading of low vs high contrast. There are known examples of high contrast noise as well as examples of low contrast (but still valuable) signal variations. Part of that may be due to NIH bias - it is a for-profit "proprietary" process after all.

    Scott
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  27. Originally Posted by Cornucopia View Post
    I find it ironic that you do all this boasting, but don't understand that you CANNOT get any more resolution out of DV footage, whether you transfer as DV, or convert to analog and capture with a 4k card, regardless of your pronouncement of Nyquist theorem backing.

    Btw, that NR paper is interesting and has some good ideas, but it is quite flawed in its assumption of the breakdown of noise vs signal in its reading of low vs high contrast. There are known examples of high contrast noise as well as examples of low contrast (but still valuable) signal variations. Part of that may be due to NIH bias - it is a for-profit "proprietary" process after all.

    Scott
    I never told that the idea was to get more resolution out of a DV footage, the idea it's to use a basic principle, already been used by professionals in this area, to have the most amount of pixels possible to work with, as I have already posted this video to show exactly that:
    https://vimeo.com/84135659

    You notice at the beginning around 0:54s when he say that the film took a week to scan a 90 min negative, you do this because you need the biggest amount of pixels to work with, and once you are done cleaning, repairing and noise removing, when you shrink it back to 2k, you get a very smooth and pristine end result, this is the Nyquist theorem in action. This are the details hidden in plain site that only people that work with this know about.

    The basics found on those papers works, you can see it on the imagem from my old image of Vanilla Ice back cover CD, here is the basic algorithm.


    And of course is for profit! People want to get paid for their hard labor.
    This tools are available for Blackmagic Davinci and many others, don't know if it will ever come to Avisynth because someone will have to do a really hard work to put this together.
    Last edited by amaipaipai; 14th Jul 2018 at 02:51.
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  28. Here a few illustrations showing this HI/LOW filters and all this discussions in video for easy understanding.
    https://www.youtube.com/watch?v=oeqQSkTFiYw
    https://www.youtube.com/watch?v=E0PqWW-exIg

    With all this used together, people can replicate what I did with the karaoke lady and the back CD cover, and be used to restore old tapes, films, etc.
    I hope now this is clear enough.
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