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View Full Version : Workflow question & Ghosting (I think) in my video


mo418
19th May 2015, 21:48
Hi All,

I own honestech VHStoDVD 4 Deluxe. I tried this plug and play capture but it didn't go very well. Laggy video and video output quality could be better (despite the highest setting set). I have a 8mm camcorder directly plugged into the device. It has one video out (yellow) and one channel audio out (white). The Honestech device is this http://www.honestech.com/main/vhs-to-dvd-40-deluxe-old.asp

So I searched the internet, and found out I could use this hardware combined to VirtualDub to capture video.

After having a look at the captured video, I wondered what was those horizontal lines, and discovered this was interlacing.... And so on for many other things observed.

I had questions/encountered issues, so googled a lot, hence learned a lot on the subject. So what was first intended to be plug and play work, is now consuming me a lot of time (which is ok for me since I like learning everyday). Still I consider myself a noob because I'm never 100% sure of what I'm doing.

First of all, I have a workflow question and was wondering if I'm proceeding ok:

1 Capture
Honestech Hardware

RCA cable
USB 2.0


Virtual Dub Software

Video (Lagarith)
Audio Uncompressed (Direct Stream)


I get audio sync issue, but it is fixed value so....

2 Edit (for audio)
Virtual Dub Software

Video (Direct Stream)
Audio Uncompressed (Direct Stream) + Interleaving (value for Skew)


3 Deinterlacing
From web search, found Avisynth and QTGMC
VirtualDub
Avisynth script loaded

Here is the script
AVISource("filename_with_audio_corrected.avi")
AssumeTFF()
QTGMC( Preset="Slow" )

Video (Fast Recompress)
Audio Uncompressed (Direct Stream)

4 Encoding
I wish to use x264 encoding, and mp3.
Already did once, worked, but have ghosting (I think)...


So my first question would be:

Am I proceeding ok? Is there a step I could avoid to save some time or to have better quality?

My second question is about this (see images below). I thought this was chroma shift but after noticing it on many capture, I guess this is ghosting. I would like to confirm with you what is this phenomena.

This is an example of raw capture (interlaced)
http://1drv.ms/1LiBm3W
http://1drv.ms/1LiBm3W

These are examples of deinterlaced video with qtgmc in virtualdub
Notice the halo (ghosting?) aside the man's shirt...
http://1drv.ms/1S8NaKJ
http://1drv.ms/1S8NaKJ

Notice the strange effect on the car's rear light (chroma shift or bleeding? Noise? Ghosting? I couldn't point out from web search...)
http://1drv.ms/1S8NqcK
http://1drv.ms/1S8NqcK

Notice the Referee (edge of his pants showing on the boards, and white of the boards showing on his pants)
http://1drv.ms/1cN9rgC
http://1drv.ms/1cN9rgC

All this being said, any help would be appreciated.

Thanks (a lot) in advance!

manolito
21st May 2015, 14:47
Hi mo418,

first of all congratulations on your workflow. Especially for the decision to use your box together with VirtualDub instead of just using the software which comes with it and try to convert the input on the fly.

Analog capturing is not an exact science, it is at least partly some kind of an art (this quote is not by me...). Using a lossless video codec like Lagarith and uncompressed PCM audio is the best you can do. Audio sync problems are common during analog capturing, and Vdub does an excellent job correcting mismatches between video and audio clock signals. But you say that you already found a way to correct audio sync, and whatever works for you is OK.

Deinterlacing with QTGMC also gives you the best available quality today, no way to improve this.


So my point is that all of the artifacts you are seeing are probably already present in the source. I do not believe that any of these things have been introduced by your capturing workflow.

You will find some very elaborate (and very slow) AviSynth scripts to improve VHS captures here on Doom9. Mostly from my experience I question the usefulness of all this stuff. If you cannot distinguish your analog captures from the source, then you pretty much achieved your goal. Of course you should correct some obvious flaws like levels and gamma, but you will never get DVD like results from analog sources.



Cheers
manolito

mo418
21st May 2015, 15:30
Hi!

Thanks for your time.

So from what I understand, the best way to verify this would be to plug the camcorder to a vcr and check if the artifacts are present on the tv?

I tried a ghost removal plugin for avisynth, but it totally messes the video.

I think I will also try to buy high end RCA cables (instead of cheap thin ones) to help the overall result .

Thanks again