How to clean up...

[VJ]

Nope, not spring cleaning...


I'm finally beginning my steps in the world of Capture. Yesterday, I tried capture from a VHS tape (poor quality), via my ADVC110 to computer, using Pinnacle Studio 8 (came with my DVD writer). Capturing (not lacking diskspace, I choose to DV) was no problem: 0 dropped frames, audio perfectly in sync, ... So I know I could start authoring a DVD.

However, the image quality is not terrific (fuzzy), so I wonder if there are any generic filters I could apply?

Worse is the audio. First of all, the volume is relatively silent, and throughout the audio track is a noticable hiss. It is extremely constant (both in frequency and in volume), so it should be fairly easy to filter out. How does one filter out these kind of things? What softwares?

Thanks!


Jörg

[Dr Mordrid]

Poor quality tapes can doom you from the get-go.

The only way I've found to mitigate (unfortunately not cure) the problem is to use very good cables with gold connectors, clean the playback heads and pass the source through a video processor before it hits the capture device.

Good video processors correct for synch losses, defective color burst and many other defects as well as amplify the signal. As with other video hardware the more you spend the more it can do.

Video processors can run from affordable to price point numbers you don't even want to know

In my case I use an Elite Video BVP4 Plus, but that runs $729 USD;

http://www.elitevideo.com/index.asp?PageAction=VIEWPROD&ProdID=8

Other options are available, but with less capability. One of the more affordable ones at $219 is the Sima Color Corrector 2;

http://www.simacorp.com/products/item.ep.html?id=478

No guarantees though.

You might want to start with just the cables, a VCR head cleaner (DRY!!) and maybe a cheap video amplifier, but don't get your hopes up.

Dr. Mordrid

[xortam]

... a VCR head cleaner (DRY!!) ...

Why dry?

[VJ]

Dr Mordid: The problem is twofold: one, it is a TV recording which was made in the 70's; and two it was recorded with a cheap 2 head vcr Still, I'd like to keep this recording, and can make some effort in digitizing it. I won't purchase any hardware for it though.

It just hit me that my current VCR has different imagefilters on board (soft, bright, ...) and I have used them during playback in the past with quite good results. So I'll try to capture again.


Much more importantly is the audio track. What is the best way to get rid of a constant hiss in the sound (and to up the gain as well)?


I wanted to use virtualdub, but it says it doesn't have a dvsd codec (can't work with directshow filters). Anyone know of a dvsd codec that works with virtualdub?
edit: Canopus offers a DV Codec download. Would this one work?



Jörg

[Brian Ellis]

Firstly, other than time base correction, video filters to correct quality problems are necessarily a compromise. Take noise, for instance. If you have a uniform grey background and suddenly on one frame a single pixel is different in intensity or hue, the filter will try to mitigate the effect by blurring it, so that it becomes less obvious. Unfortunately, it will also blur wanted changes of intensity or hue, such as the corner of a building. If you have a blurry image to start with, such as from a VHS tape, the extra blurring will hardly make a noticeable difference, but the sharp noise signals will be reduced, at least until you jack the noise reduction filter up too high and you will start getting artefacts. The opposite effect is sharpen; this will enhaance the noise as it will try to reduce the number of pixels in transitions within the image. This has to be used with great care, because it will exaggerate all the defects due to the tape. In other words, it's GIGO, even if the garbage out has been changed to enhance one problem at the cost of another.

As for audio, there is every chance that your recording is mono, but your DV stream is stereo. If so, your LH channel is just noise. If you download a software like Audacity (open source and free), you can duplicate your RH channel to replace the LH channel. This should reduce your perceived noise level by ~6 dB. Then you can use the excellent filter for noise elimination, if you wish. You specify a part of the sound track that is just noise and nothing else. It then removes this noise from the whole track and filters out the consequent distortion. You can achieve noise reduction of 20 - 40 dB thuswise, with very little loss of sound quality. However, again, a cautious approach works best; minimise noise reduction to just acceptable rather than try to remove it all.

[LvR]

Panasonic VFW codec for use under Virtualdub

[Technoid]

..... a VCR head cleaner (DRY!!)......
Dr. Mordrid

Unfortunatley they seems to have evaporated here in sweden

and every videostore sells those "poure a gallon of stinky fluid in it, plug it into your vcr and pray" cleaning tapes

[VJ]

Brian: The signal sent by the VCR is a stereo signal (even though the original recording most likely is mono); both DV audio channels contain audio. Still, I hadn't thought of using Audacity... No doubt this will get the job done. Can Audacity extract the audio from the avi file?
What is the best workflow? I'm thinking:
1. Cut the avi in the parts I'd like
2. Extract the audio
3. Process the audio
4. recombine them during the rendering to the final format


Lvr: Cool, thanks!


Jörg

[Brian Ellis]

Looks good. Your editing app should allow you to convert the DV audio to wav format and vice versa.

[VJ]

Thanks!

I'm still looking at what is the best editing application for me... Currently, I have Avid Free DV, Pinnacle Studio 8 and Virtualdub.
(Pinnacle came with my DVD writer, the others are free)


Jörg

[landrover]

VJ,

have you tried Video deLuxe 2005 by Magix? It's cheap, has a sh*tload of features and handles audio processing really well, with preset filters as well as manual filtering. You can get a trial version at www.magix.net. Just keep in mind that the full retail box is often sold much cheaper than Magix' "download only" version.

[VJ]

Looks good. Your editing app should allow you to convert the DV audio to wav format and vice versa.

I had to change my workflow... Now, I did this:

1. save wav from (using VirtualDub)
2. filter noise + gain (using Audacity, worked great!)
3. filter video (using VirtualDub: VHS filter, SpotRemover and sharpen) + combine with the filtered audio

I'll split up the file afterwards. The reason for doing it like this is that I had a perfect noise sample in the very beginning of the audio. If I were to find this after cutting up the 3 hour 30 minute movie, it would be difficult.
As in step 3 the audio is just put back using a direct stream copy, I'm guessing I won't loose any audio quality here.

Currently, my PC is filtering the video (EET 20 hours )

4. split up the file in required sections
5. author the dvd


Jörg