Query: vhs being "upscaled"...........

[ianj]

Hi all,

Is it possible for a vhs copy of a programme(about 240 lines??) to be ran through some sort of a line standards converter to "upscale" the picture to a better line quality--say, something approx. dvd quality.................
The reason Im asking, is that we want to colourise the programme material, but the standard vhs recording is deemed not good enough--could every other line from the signal, somehow be "extrapolated" and added to the output to the dvd recorder, giving the "impression" of a better signal, to work with?? ianj

[ppppenguin]

Silk purse out of sow's ear

You can't put back resolution that isn't there. When you say 240 lines I'm guessing you mean limited luminance resolution, not a reduced number of scan lines. You seem to be confusing one with the other. Are you working with standard 625 line pictures or some other standard (such as 405) that happens to be recordable on VHS?

Companies such as Snell and WIllcox have made some very expensive signal processing equipment that can help to get the best out of poor quality material. There may also be software that can run on a PC to do it, albeit probably rather slower than real time. Timebase instability, noise and various other parameters can be improved by judicious processing. When all's said and done, if the resolution isn't there, it can't be put back.

[Duke_Nukem]

Not sure I fully understand ... are we talking a standard VHS tape ?

You need to get the recording into your PC then there will be lots of options. Also depending upon the nature of the poor quality of the tape, a sync stabiliser may well help (note though I mean a true sync stabiliser such as built in to the Canopus ADVC300, not those that are meerly macrovision defeaters).

You can work wonders to improve a recording with certain types of faults, but at the end of the day if the resolution isn't there in the first place then it never will be.

Can you post a couple of pics of the nature of the problem ?

TTFN,
Jon

[ianj]

no, sorry--I cant post any pictures--the tape isnt in poor quality--its just a normal vhs tape, but on a big screen it looks poor now compared with dvd--when I mentioned the lines at 240, I was meaning the resolution quality? Many thanks, ianj

[paulsherwin]

Originally Posted by ppppenguin

Companies such as Snell and WIllcox have made some very expensive signal processing equipment that can help to get the best out of poor quality material. There may also be software that can run on a PC to do it, albeit probably rather slower than real time. Timebase instability, noise and various other parameters can be improved by judicious processing. When all's said and done, if the resolution isn't there, it can't be put back.

Some of the professional digital processing systems can do amazing things when used by a skilled operator. In this case it is possible to 'improve' the resolution by interpolation techniques, edge discovery etc. Quite a bit of human involvement is required. I don't think this can be done by an amateur with a PC though, and paying the pros to do it will be expensive unless the subject matter is very important and/or valuable.

Paul

[Duke_Nukem]

A lot can be done using VirtualDub ( www.virtualdub.org ). It supports 3rd party plug-ins of which there are quite a number. I'm not claiming it'll beat the professionals, but with effort you can certainly improve matters, such as increasing the colour saturation, adjust the hue, smart noise reduction, temporal smoothing, de-interlacing, and so forth.

And best of all, it's free

TTFN,
Jon