Interlaced video captured from VHS - what next?

[Mehedict]

I have some old VHS captured to 576i PAL format, 50 frames per second.

The problem is what do I do with INTERLACED video???

As interleced video doesn't look good on any of my LCD TVs, I am about to simply convert it to 25 FPS progressive with Adobe Premiere Elements. After conversion to 25p it looks GREAT, no signs of interlace at all but here's the question:

If I put it to progressive 25p format, don't I LOSE half of the video?

Is there any other way to make it look good on LCDs other than converting to progressive? It looks like the best solution but I'm afraid it will waste half of the data. I do not know what algorythm Premiere Elements uses to convers interlaced video.

THANKS EVERYONE

[manono]

I have some old VHS captured to 576i PAL format, 50 frames per second.

It's 25 interlaced frames per second, 50 fields per second.

So, it's really interlaced? You can see the interlacing/combing? And it's not a movie but maybe some home movies or something like that?

One thing's for sure, your TV sets' deinterlacers are better than the one in Premiere. Therefore you're doing something wrong if it looks bad on your LCD TV sets. Maybe you're cropping and resizing the video?

If I put it to progressive 25p format, don't I LOSE half of the video?

You lose half the temporal information (if deinterlacing to 25fps). It won't play as smoothly. Also because the deinterlacer will create frames from fields, the resulting frames won't look exactly as whole originally progressive frames will look. How different or how poorly they might look in comparison depends on the quality of the deinterlacer. In general, it's not a good idea to deinterlace if the end result is a DVD. If for YouTube, then you'll have to deinterlace, and your best bet is to use an AviSynth deinterlacer.

[DB83]

Unless I am having a blonde moment I do believe, it is possible to capture at 50 fps. You did not state what software you used.

Can you post a mediainfo report of the captured file just to confirm that the capture is really 50 fps.

But if the file really is 50 fps then that really is your error. It is quite possible that by capturing at 50 fps from a source that really should be captured at 25 fps it is corrupted simply by having too many frames.

Confirm that the file is 50 fps but I would suggest that you recapture, in that event at 25 fps.

[jman98]

A true 50 FRAMES per second capture from VHS source is unlikely.

One of the problems is that some programs are now reporting frames as "fields" even though this is wrong. I've done some VHS captures with the Hauppauge Colossus and VLC has incorrectly reported the frame rate on my captures. It's used the field value and reported it as frames. I posted about this and using some other programs confirmed that the frames per second were actually 29.97, which I would expect from VHS input in the USA.

The original poster's problem may be in part that his TV just displays everything in 16:9 and of course his 4:3 VHS captures look like crap when stretched to 16:9 but somehow his deinterlaced videos look OK (to him) when stretched. This is just a guess. I can't speak for Europeans but in the USA the majority of consumers with HDTVs watch EVERYTHING in 16:9, even 4:3 sources.

[DB83]

Good point jman98.

One must also ask by what medium the capture file is being played on to the tv's.

We have very little info to go on. At the end of the day the video could be fine and just the hardware combo is creating a wrong impression.

[Mehedict]

I can confirm it is regular PAL format, that means yeah, 25 interlaced frames per second, but each of the 50 fields contain some real information about the video, that's why referred to it as 50 FPS. My mistake, sorry. It feels like 50 FPS though, it's really smooth. It's an old camcorder footage, not a 24p movie.
The reason it looks bad on any LCD is because PAL is designed for 50 Hz TVs and PC monitors run typically at 60 Hz and TV is also hooked up to my PC so that one is 60 Hz as well. It doesn't do any deinterlacing, it just displays what the PC sends over the cable and that's progressive scan format. I either rely on VLC player's features to deinterlace in real time, or export it as 25p right from Premiere Elements 10.
My TV may have some deinterlacing engine but that works only if it's hooked up to a device that natively sends 50i signal to the TV, which my HTPC does not. Therefore the video is interlaced all the time.
I'm sure the video is captured properly using Premiere Elements 10, it's PAL 720x576, 25 FPS (IMHO it should be referred to as 50 half-resolution frames per second).
The question is, how to make it look good on LCDs, played directly from a PC or HTPC. No burning to DVDs. I'm actually planning to convert everything to h264 as it's much better than MPEG2. I could simply put it to interlaced h264 50 fields per second, but then again, the 60 hertz screens won't handle it properly.

What do you recommend?

Thanks again and sorry for the confusion.

[juhok]

(IMHO it should be referred to as 50 half-resolution frames per second).

Why not just call it what it is, 50i.

If you want to keep temporal information and make it progressive, convert it to 50p. You want high quality, try http://avisynth.org/mediawiki/QTGMC

[Mehedict]

To clear it up, my previous post is a mess, here's the summary:

- It's 25 FPS interlaced PAL, that means it's as smooth as 50 FPS in my opinion. It's camcorder footage, not a movie.

- I'm about to play it on PCs and HTPC that all run on 60 FPS typically. That's why it looks bad all the time, PAL is designed for 50 Hz.

- If I keep it in interlaced "50 fields" format I have to rely on some software deinterlacing engine, without it it'll look bad

- If I convert everything to 25 FPS progressive it will look good, but won't be as smooth.


So again, is it a good idea to permanentely convert to 25p?

[Mehedict]

[QUOTE=juhok;2183373]

(IMHO it should be referred to as 50 half-resolution frames per second).

Why not just call it what it is, 50i.

If you want to keep temporal information and make it progressive, convert it to 50p. You want high quality, try http://avisynth.org/mediawiki/QTGMC[/QUOTE]

Thank you, haven't thought about that. Sounds logical. But I'm afraid the size of that file will double, I'm trying to keep a 4 hour VHS in under 8 GB, with double framerate that would be 16.

[DB83]

You have confused yourself to the hilt here and probably others.

The capture file is, as was reported in the first response 25 FRAMES per second PAL resolution. End of.

In my mind there is no need to convert your capture to progressive - certainly not with Mpeg2. Use your player to adjust the de-interlacing - there are several options in VLC. You may also have to check your video cards output settings if you are using tvs as, techically, second monitors.

[poisondeathray]

Thank you, haven't thought about that. Sounds logical. But I'm afraid the size of that file will double, I'm trying to keep a 4 hour VHS in under 8 GB, with double framerate that would be 16.

It won't double. If you use the proper settings h.264 uses temporal compression with b-frames.

The same approximate average frame quality can be achieved typically with ~1.2 -1.3x the bitrate for 25p vs 50p

Double the frames would only lead to double the size if you coded each frame independently (all I frames), with CBR, not VBR.

Of course it will depend on content characteristics. Highly compressible content like slow movement, controlled shooting, or cartoons often only takes ~1.1x . Difficult to compress content, like shaky, noisy handheld home movies might take ~1.5x the bitrate

4h assuming 128kbps audio, will be about 4.6Mb/s video bitrate. That's sufficient for decent quality 576p50, especially if you've prefiltered, cleaned it up etc... if you use a good encoder like x264

Realtime software deinterlacers, and hardware deinterlacers definitely yield worse quality than slow processing like QTGMC . You can get 95% of the quality of QTGMC by using faster preset settings (instead of being horrendously slow, it's just slow)

Do some small tests and see if it's worth the tradeoffs (mainly in processing time)

[Mehedict]

Thanks.

So it seems I'll be deciding between

- interlaced h264, relying on relatime interlacers.

- converting to 50p h264, as you say it uses some smart temporal compression

I'm going to google something about the QTGMC thing. Just to ask, the Premiere Elements 10 50p exporting engine does a great job, or a bad job in terms of deinterlacing? It looks great to me, but if someone know what exactly's going on there, let me know.

[poisondeathray]

I'm going to google something about the QTGMC thing.

There are a bunch of comparisons posted. Some of them might be under "tempgaussmc_beta1" (the precursor ot QTGMC)

Just to ask, the Premiere Elements 10 50p exporting engine does a great job, or a bad job in terms of deinterlacing? It looks great to me, but if someone know what exactly's going on there, let me know.

I don't use elements, but if it's the same as premiere pro , it doesn't do a very good job, resulting in either:

a) blend deinterlace - blurry results,
b) simple bicubic resize of fields - aliasing , jaggies, "marching ants" artifacts

It's AVC encoder (based on Mainconcept) isn't that great either compared to x264 (again many comparisons posted)



Note - For better quality, proper VHS capture requires much much more in terms of hardware (TBC) , proper capture hardware, both software and hardware processing. There are many threads covering these topics

VHS is always noisy and usually requires some sort of denoising. Even pristine retail VHS tapes can benefit from light processing

[2Bdecided]

Wo, hang on, stop for a moment guys...

I either rely on VLC player's features to deinterlace in real time

Yes, good, so do I - that's how I watch all my SD and HD interlaced content using my PC.*

So what's the problem?!

What not just use VLC to play the files, and be happy?

Cheers,
David.

* - not strictly true - I have DV-AVI files assigned to MediaPlayerClassic because VLC gets confused about the field order. But all MPEG and HDV goes through VLC.

[Mehedict]

2Bdecided: VLC works great but I originally attempted to be software independent when playing.
Post processing, denoising and additional work may be done after I capture everything, I'm not planning doing it right now. I have a Canopus ADVC-55 and a Panasonic VHS player. Do you think it's bad equipment?
I probably won't be able to get anything better.
Any way to get the x264 encoder right into Premiere Elements?

[2Bdecided]

2Bdecided: VLC works great but I originally attempted to be software independent when playing.

Nothing is truly software independent - you have to install something . The most common global format is interlaced MPEG-2, but that doesn't play natively in most windows systems (until you add DVD player software or similar). Native in windows is MPEG-1 and WMV, but you wouldn't use those. It's true that more software works OK with progressive footage by default than interlaced, but some software (especially on lower powered systems) doesn't really like 50fps progressive footage.

Post processing, denoising and additional work may be done after I capture everything, I'm not planning doing it right now.

Then you should save the original interlaced capture until you do. After processing, you can choose to output the finished product however you want. You might do different versions for different things (interlaced DVD, 25fps for YouTube, 50fps for your own viewing on PC etc).

I have a Canopus ADVC-55 and a Panasonic VHS player. Do you think it's bad equipment?
I probably won't be able to get anything better.

Ideally you'd have a line-TBC somewhere, probably in an S-VHS player. But if the picture on your tapes is stable (no wobbly picture, no bending/tearing, no jaggedness), and there are no sections with bad signal that cause your capture device to drop out, then you'll probably be OK. Many people capture lossless, but using DV-AVI instead of lossless makes a tiny difference compared with choice of VCR, quality of tape, use of TBC, etc.

Any way to get the x264 encoder right into Premiere Elements?

sorry, don't know.

Cheers,
David.