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Yo
23rd March 2008, 18:22
Source material--an MPEG-2 file recorded from VHS years ago. I believe the capture device was ADS DVD Express, which captures directly (hardware encoder) to MPEG-2. Probably captured with Ulead Video Studio. The video bitrate of the MPEG-2 is 2000kbps, 704/480 resolution, frame rate 29.970fps. (The original material was from a TV show, not a movie, recorded to VHS years ago.)

Now--I tried encoding that MPEG-2 to MP$, for playing on an Ipod, including TV Out.

I tried Handbrake, using high-rez Ipod preset, which I modified as follows. As the MPEG-2 is interlaced, I added the deinterlace filter-slow. I added the denoise filter-medium, thinking that might help.

The original MPEG-2 has the problem, besides the interlacing, of flickering. Is that always a problem in VHS transfers?

The resulting MPEG-4 flickers just as bad, but now there is also bad blocking. I even tried again with HB's deblocking filter, but that didn't help at all, stilll real bad blocking.

What could cause the blocking, in transfer to MP4? Could the denoise filter cause that? Better not to use it?

Is there any kind of filter that can remove (or lessen) the flickering?

Perhaps it might be a good idea to re-do the capture from VHS, in a different way, but I don't know if I can find that VHS tape. (But in case I find it, you could give suggestions for re-capturing it.)

However, in working with the MPEG-2 file that I have now, what could I do (in converting to MPEG-4) to reduce flicker, and eliminate the blocking? (Again, the flicker occurs in both the MPEG-2 and converted MPEG-4, but the blocking only occurs in the latter.)

Thank you for your suggestions. :-) :thanks:

nm
23rd March 2008, 19:32
What exactly do you mean by "flicker"? Maybe you could upload a sample clip (to mediafire.com (http://www.mediafire.com), for example) so that we can see for ourselves.

Blocking is usually caused by too low encoding bitrate, compared to video resolution and complexity. What bitrate and frame resolution did you use? Or, better upload a sample that shows the blocking problem too.