VHS colour saturation issues (screenshots included)

[meshead]

Not sure how to resolve this issue. There seems to be a lot of blue and not a lot of other colour. I am begining to think it can only be saved by taking the colour out completely, but in certain frames you can tell ther correct colours are in there somewhere. Please advise!

[titigrom]

Hello !

Excuse for my english because I'm french.
It's an old video you've got. What capture device did you use ? Is the video source correct when it's viewed on TV or is your snapshot like original ? It seems to be very bright and unfortunately it is difficult to find a way to solve this issue.

I don't know if there's a video software which includes a filter called "chromatic correction" : you said sometimes you had colors that appeared. And I tried to correct a little your snapshot with an imaging software. See the result yourself.

Voilà, I 've given you few hopes.

[jagabo]

VirtualDub's ColorMill filter can do color corrections like titigrom posted.

I don't know how you're capturing but if you can do anything to reduce the over bright captures you'll be in much better shape. Otherwise, you can bring out a little more detail in the overly bright areas by changing the luminance while the video is still in the YUV colorspace. AviSynth can do that with the ColorYUV() filter.

[meshead]

Yes titigrom Je suis tres heureux avec vos resultats. Your English is very good. I am using VirtualDub and AviSynth. But i also have access to Premiere Pro CS3. Unfortunately the capture is the same as the results I get when watching it on the telly through a VHS player. I guess over the years it just deteriated I will look for a chromatic filter for VirtualDub. How exactly did you get the results in your picture? It looks much much better!

Thanks for your help!

[redwudz]

My attempt looks about the same as titigrom's. I put it in VirtualDub Mod and used the ColorMill filter: http://fdump.narod.ru/rgb.htm The brights are way too high and there's not much there to work with. Of course it's different with a video as it's changing all the time. I would give it a try though. You may at least get the colors a little closer.



EDIT: And to get those results, I just played with the different settings. Nothing scientific or ordered.

And welcome to our forums, meshead and titigrom

[meshead]

Yes, unfortunately, in this scene in particular there seems to be a lot of light pollution. Like you say, there's not a lot I can do about this. Thankfully it is only very bad in this scene, and not really an issue in the majority of the tape. I will give ColorMill a go, but i can't seem to access the website at the moment....i will keep trying

[redwudz]

It's a very slow website for the ColorMill filter. You might try a Google search and find it somewhere else, or just keep trying.

[SatStorm]

Try also the MSU filters

MSU Old Colour Restoration

MSU Colour Enchancement

MSU SmartBrightness

[meshead]

with filters on in virtual dub i cannot do a 'direct stream copy' 'full processing mode' takes up a huge amount of disk space, but i would rather not re-encode the video. Is it possible to apply these filters without re-encoding?

[meshead]

here's a little screenshot of the sort of results i'm getting with colormill

[titigrom]

Wow ! I'm surprised by the replies and Happy to help people meshead

So many ideas and discoveries I made about some features of VirtualDubMod and filters which were unknown to me.

And yes, old tapes are often problematic with brigthness. I have some videos from 80's that looks like yours, meshead.

with filters on in virtual dub i cannot do a 'direct stream copy' 'full processing mode' takes up a huge amount of disk space, but i would rather not re-encode the video. Is it possible to apply these filters without re-encoding?

Sorry to tell you that, but it's necessary for VirtualDub (or VirtualDubMod) to re-encode your video if you want to apply any filter (Full Processing Mode). And the file size after the processing depends on your source. Low quality and noisy source often makes file size bigger...

You must know if you are looking for the best result or a little file size and thus poor quality of the video. And you said huge amount of disk space -> use a video compression (Xvid, etc.)

[Marvingj]

ColorMill filter will work along with a color corrector hardware. I've done it before. You should be OK..

[redwudz]

Video editing or filtering does use a lot of disk space. If you wanted to preserve the quality for a re-encode to MPEG for a DVD, you might want to use a lower compression codec, such as HuffyUV or DV-AVI. DV will use about 13GB per hour, HuffyUV a lot more. Xvid's not really a good choice, you will lose a fair amount of quality just with the encode to it, then the encode to MPEG.

Some options, depending on your software, is frameserving the filtered video directly to the MPEG encoder and not creating a in-between file. That will save quite a bit of hard drive space. VD or VD Mod can do that. I frameserve to TMPGEnc encoder, but other encoders should also be able to read the file.

One guide for VD frameserving: https://www.videohelp.com/oldguides/virtualdubframeserve

A better method would be using AVISynth for the filtering and frameserving. It's much quicker and more flexible, but has a fair bit of a learning curve.

[jagabo]

Levels and Colormill in VirtualDubMod:



Looks like faded 1960's era 8mm film converted to VHS.

[meshead]

Video editing or filtering does use a lot of disk space. If you wanted to preserve the quality for a re-encode to MPEG for a DVD, you might want to use a lower compression codec, such as HuffyUV or DV-AVI. DV will use about 13GB per hour, HuffyUV a lot more. Xvid's not really a good choice, you will lose a fair amount of quality just with the encode to it, then the encode to MPEG.

Some options, depending on your software, is frameserving the filtered video directly to the MPEG encoder and not creating a in-between file. That will save quite a bit of hard drive space. VD or VD Mod can do that. I frameserve to TMPGEnc encoder, but other encoders should also be able to read the file.

One guide for VD frameserving: https://www.videohelp.com/oldguides/virtualdubframeserve

A better method would be using AVISynth for the filtering and frameserving. It's much quicker and more flexible, but has a fair bit of a learning curve.

Some interesting suggestions. IF i "save as avi" in full-processing mode in virtualdub is this lossless. The resulting file is "raw bitmap" whatever that means.

I have some experience with AVS, just find it annoying that there is no preview. without a preview tweaking takes absolutely ages to get just right. If i opened an avs script of the movie in virtual dub i can use "direct stream copy". I don't know why VirtualDub won't allow direct stream copy with filters enabled because i was under the impression that VD and AVS use filters in the same way.

My ideal scenario would be to do a lossless edit, using filters and real-time preview, without re-encoding or losing any quality. It seems easy enough to maintain quality (by saving as 'raw bitmap' in full processing mode) but in doing this I lose the compression and to re-encode would lose quality again.

One idea i did have would be to use the settings i have in VirtualDub (i've got them just how i want them now) and create a avs script using the same filters. I could then import that script to virtualdub and "direct stream copy". The only problem with this is that i cannot copy the filter configuration I have in VirtualDub accurately into an AviSynth script as far as i can see. Is there a way of doing this, or am I getting a little muddled here?

[jagabo]

IF i "save as avi" in full-processing mode in virtualdub is this lossless.

It depends on your source. Presumably your source is in a YUV colorspace (DV AVI maybe?). VirtualDub converts this to RGB for filtering. All source pixels with a limunance below IRE 0 (16) will become the same as IRE 0. Any pixel with luminance above IRE 100 (235) will become the same as IRE 235. This means any detail in very dark or bright areas will be lost. There is also a little precision loss (not every RGB value has a unique equivalent in YUV and vice versa) but this is of a minor concern. Given the over bright nature of your source this loss of bright detail will be a concern. You can avoid this by using AviSynth to do the YUV to RGB conversion. Use ConvertToRGB(matrx="PC.601). You'll need to do a little levels adjustment afterwards. It would be even better to leave the video as YUV and do all your filtering in AviSynth but it's much harder to set up all the filters in AviSynth -- as you know.

If i opened an avs script of the movie in virtual dub i can use "direct stream copy". I don't know why VirtualDub won't allow direct stream copy with filters enabled because i was under the impression that VD and AVS use filters in the same way.

Direct Stream Copy doesn't allow for any filtering -- period. It doesn't decompress the input if it's compressed, and it doesn't change the colorspace if the video is already decompressed. It's only useful for remuxing or converting audio without touching the video.

One idea i did have would be to use the settings i have in VirtualDub (i've got them just how i want them now) and create a avs script using the same filters. I could then import that script to virtualdub and "direct stream copy".

This makes no sense. Using VirtualDub filters in AviSynth will require conversion to RGB. AviSynth will then be feeding uncompressed RGB to VirtualDub. Saving that in Direct Stream Copy mode will get you exactly the same thing as doing your filtering in VirtualDub with Full Processing Mode.

If you want a smaller file from VirtualDub try using Lagarith as the compression codec. It has a lossless mode for RGB, a near lossless mode where it converts RGB to YUY2 then compresses, and a few other options. Depending on the video it usually delivers files 1/2 to 1/3 the size of the uncompressed data.

[grannyGeek]

Hi meshead

As Jagabo says, for this current project you have, running the VirtualDub filter inside an avisynth script will create an unnecessary color conversion, and your source is pretty fragile, it might not stand up under so many conversions.

However, if you ever do need to use a VirtualDub filter inside a script, this is how it can be done. (I have done this to use ColorMill, DeFlicker, DotCrawl, and others)

Load video into VirtualDub, and tweak the filter settings to desired settings.

Go to File > Save Processing Settings, and save the file to an easily accessible name and folder, it adds the .VCF extension automatically.

In the AviSynth script, put the line, for example --
LoadVirtualdubplugin(vdPath+"colormill.vdf", "colormill",1)

where vdPath is the path to where the plugin is installed.
The entry "colormill" tells AviSynth that this is the name I will use to call the plugin.

Then use Notepad to open the saved VCF file, and almost at the bottom, find a line that looks like this --- (these are the configuration settings for Colormill)

VirtualDub.video.filters.instance[0].Config(25700, 45924, 7268, 25700, 36452, 14235, 42596, 25665, 25700, 25700, 25700, 25700, 25700, 1124, 5);

Now open your AviSynth script.
If your video is not in RGB, you must add a line to ConvertToRGB32()
or as Jagabo recommends, add the line
ConvertToRGB(matrx="PC.601)
( the PC.601 setting will probably make your video look a little lighter and maybe black looks a bit washed out, so you may have to adjust Levels afterward, and if you happen to be using Colormill, you can do some tweaking with that.)
Add a line to call ColorMill, and in parentheses, copy and paste the setting numbers that follow Config. I usually put in a backslash line-continuation symbol in all my long script lines so that I won't have to scroll sideways across the page.

Script should look something like this---

LoadVirtualdubplugin(vdPath+"colormill.vdf", "colormill",1)
ConvertToRGB(matrx="PC.601)
colormill(25710, 44388, 31069, 25699, 26212, 25708, 26468,
\ 28516, 29028, 25700, 27260, 25701, 25700, 1124, 5)

Refresh your script, and see how it looks.

I sometimes must go back and tweak a bit and save a new VCF file, because my captures are in YUV and converting to RGB affects the color range a bit.

hope this helps.

EDIT ADDED --
oops , forgot to add --
If your Avisynth script continues on to use Avisynth filters after the VDub filters, you must add another line to convert back to the colorspace the Avisynth filter works in.
ConvertBackToYuy2() << convertBACKtoYuy2 only works following conversion to RGB, not from any other colorspace >>
OR ConvertToYuy2() OR ConvertToYv12().
Hope this wasn't too confusing, and hope I didn't just add useless information you already knew.

[grannyGeek]

Meshead, I also meant to mention --
You find it frustrating to have no preview while working with Avisynth scripts.

The program I've used for quite a while is VirtualDubMOD, because it has a built-in Script Editor on the Tools menu. You can open the Script Editor window, write your script in there, and after you have saved the script the first time, just hit the F5 key after every tweak to "Refresh" the VDubMOD video display window.

It still takes time to tweak of course, but much faster than trying to edit your script in Notepad, say, and then re-load it in VirtualDub. I'm totally dedicated to using VdubMOD now.

There is another option that I've just begun trying on recommendation from Soopafresh --- there is a newish editor called AVSP that lets you script sliders to tweak your filter settings, and best of all, has tabbed windows so you can have multiple scripts available to compare in one interface.
Scripting the sliders is a little tedious, but the sliders let you tweak settings much more easily.

[arturjose]

where i can find colormill.vdf
thank you

[redwudz]

colormill2.1.1.zip

[arturjose]

Thank you.