90s Video Footage What is this called? noise? jitter? hash? streaks?

[SupraGSX]

Hi all, I'm uncertain as to the technical term of what I'm seeing on this footage and that makes it difficult to find a filter to repair the problem. It looks like tiny two inch long streaks that pop up randomly and give a jitter or sense of movement on an otherwise static picture. The video is actually in pretty good quality other than this issue. It is very visible if you focus on the Monte Carlo on the front of Dale Earnhardt's car. An explanation of what I'm seeing along with a script to repair it would be a big help. I did have luck repairing it with Topaz using their reduce jittery motions filter. However, this filter is on or off with no settings for strength and while it helped with this specific issue it caused a lot of other issues such as blurring the entire frame at any camera scene change. This leads me to believe the problem is best fixed in avisynth. Thanks in advance for any help.

[johnmeyer]

The footage looks fine to me. I don't see anything that needs fixing. Yes, there is an infinitesimal amount of noise in the letter "M" on the front bumper of the car and if that is what you're talking about, I'd just live with it and enjoy the footage. It will be very hard to repair without introducing problems that are more severe than what you fix.

[jagabo]

Poor deinterlacing, overshoots at high contrast edges, flickery 30p... You can alleviate the problems a bit in software. But a new cap with a better VCR and proper capture device could do better.

[SupraGSX]

Unfortunately, I don't have untouched original footage. This is the best quality version of this race I could find and is all I have to work with. What can be done in software to help?

[SupraGSX]

Jagabo, could you share the script you used?

[rrats]

why's the video resized to 720p

[jagabo]

Jagabo, could you share the script you used?

I think it was this:

AviSource("The 1997 Winston.avi") 
Crop(160,0,-160,-0)
QTGMC(InputType=2)
RemoveDirtMC(20, false)

QTGMC was used to reduce some of the deinterlacing artifacts (and some of the overshoot streaks) and RemoveDirtMC to remove the bulk of the overshoot streaks.

[SupraGSX]

Thanks Jag. Just to clarify I haven't touched the footage it was uploaded on nascar's YouTube channel. There was actually also a 720p60 version and upon downloading that version it was just a version that had every frame repeated, so this is the one I went with. I like to clean up the audio and video and archive them because any day nascar could decide to pull them down and while these aren't perfect they are miles better quality than anything else available. Races are 3-4 hours long so it's not like any were recorded in sp mode. Gotta take what you can and try to make it as best as possible.

[jagabo]

I also made a version that only applies the RemoveDirt() to the most saturated parts of the picture:

##########################################################################
#
# Saturation, returns mask, 0 to 180
#
##########################################################################


function SaturationMask(clip c)
{
    U = UtoY(c)
    V = VtoY(c)
    mt_lutxy(U, V, expr="x 128 - abs 2 * dup *    y 128 - abs 2 * dup *   + 0.5 ^")
    PointResize(c.width, c.height)
}

##########################################################################


AviSource("The 1997 Winston.avi") 
Crop(160,0,-160,-0)

QTGMC(InputType=2)
satmask = SaturationMask().ColorYUV(gain_y=1000, off_y=-100).mt_expand().mt_expand().mt_expand().mt_expand().mt_expand().mt_expand()
Overlay(last, RemoveDirtMC(30, false), mask=satmask)

# FrameRateConverter() # optional double frame rate, motion interpolated

You'll probably have to play around with the threshold and such.

[SupraGSX]

Thanks again jagabo, I really appreciate the time.

[jagabo]

With racing video panning shots will flicker a lot at 30p. Doubling the frame rate with motion interpolation will eliminate that flicker. Unfortunately, it may sometimes lead to other distortions. But you may find the tradeoff worth it. I found that FrameRateConverter(BlkSize=24) worked better than the default for this particular clip. Also using InterFrame(cores=4) worked better than just FrameRateConverter().

[SupraGSX]

So would I use use interframe before or after framerateconverter? My understanding is interframe removes frames and I would be setting framerateconverter to double them correct? Or are you suggesting to pick one or the other?

[jagabo]

So would I use use interframe before or after framerateconverter?

Instead of.

My understanding is interframe removes frames and I would be setting framerateconverter to double them correct?

No, both are motion interpolated frame rate converters. In this case producing a new frame in-between the existing frames, doubling the frame rate.

Or are you suggesting to pick one or the other?

Yes, one or the other. Whichever works best. They both have lots of options for tuning their behavior.

Here's the video with Interframe:

[SupraGSX]

Jag, I just had a chance to play with this some more and you did amazing job. The viewability is much improved without all the shimmering. Thank you.

[jagabo]

Glad it worked out for you.