Why is de-interlaced video for VCD never smooth?

[Blackout]

Hi,

i hope you can help; i have been trying for months now to create a PAL VCD that looks smooth for smooth action. eg i have a 720x576 avi i created using my Canopus ADVC-100 of some ice skaters from the olympics, they fly around the ice smoothly.

If i make a mpeg2 SVCD file using TMPGenc it looks great on my DVD player (pioneer) when ive burnt a cd. Obviously its interlaced.

But whenever i try and create a 352x288 VCD and i have to de-interlace to an mpeg1, my video ends up looking consistently "ticky" in fast movement, ie action does not look smooth. The skaters "tick" across the screen like its bloody super 8 or something! . Footballs "shudder" across the screen when they should fly smoothly thru the air.

I dont understand how you can get smooth de-interlaced ANYTHING at 25fps from interlaced video.

Ive played for hours with the various de-interlacing settings in TMPGEnc but all they do is various forms of "ghosting" and "blending" of fields which then leaves anamaloties behind the skaters and footballs. Never looks even close to interlaced video. It seems i can either have sharp de-interlaced frames that obviously stutter from one frame to the next or i can have blurry "de-interlaced" moving images.

Ive read that de-interlacing to 50fps keeps all the frames and its smooth but thats useless when you want to make a VCD, which insists on 25fps.

This is NOT a field order problem. I know my avi is Bottom field first, i know what the problem of an incorrect field looks like and this aint it.

Is there a way to get de-interlaced mpeg1 at 25fps to look as smooth as interlaced mpeg2 at 25fps?

Many thanks,
blackout.

[Devnull]

Just the fact that you are having to deinterlace is funky. When I capture interlaced video and then encode it to vcd instead of svcd I haven't seen any interlacing artifacts unless I try to make an xvcd with the height above 240(NTSC in my case). So you have tried atleast changing the field order even if you know what it should be? Hmmm.

Well I would use VirtualDub and try the area based deinterlacing filter for it, TMPGEnc's deinterlacing filters are not the best.

[Blackout]

Hi Devnull,

thanks for responding...im not getting the traditional interlacing artifacts, such as the "rats teeth" horizontal strips. The frames are all crisp and clear and artifact free, its just when i play the file, moving images flicker across the screen instead of moving smoothly much like they do when watching super 8 film. Its almost like you can see the VCD flicking thru the frames, when it should be smooth.

Ive tried the reverse field order (field A) and i get the "skips" in frames and general unstable picture. Its not the incorrect field problem..the problem i have is more subtle than that.

I am using TMPGenc to take the 720x576 avi file down to 352x288 and to de-interlace and convert to mpg1 all in the one process...is this my downfall? Is it TMPGenc that is causing this flikkering in the process and perhaps losing frames somehow?

Many thanks,
Blackout.

[ChRaN]

look her http://www.lukesvideo.com/interlacing.html or http://www.lukesvideo.com/classifyhighres.html to determine what type of interlacing it is

[banjazzer]

If you are playing the output through a TV, is it necessary to de-interlace in the first place?

[Dave B]

The deinterlace filter within TMPGEnc is not particularly advanced and could be the source of your problem. If my memory serves me well then it only gives you the option to remove a field or simply blend the fields together. The first option can produce jittery video such as that you are seeing now and the second option will produce ghosting.

Try deinterlacing and resizing using VirtualDub and then frameserving the resultant video to TMPGEnc. A good deinterlacing filter to use is Donald Graft's smart deinterlacer (link below). It can correct a variety of field related problems.

http://sauron.mordor.net/dgraft/smart.html

[bbb]

Have you tried double field and lowering the fps to 25 fps?

[Dave B]

But IVTC is only useful for sources that have been teleclined.

The original poster was talking about personal camcorder footage.

[Blackout]

thanks for all your help, the footage was actually from TV via my video recorder SVHS outs to the Canopus ADVC100 ins which is a analog-digital convertor which spits the digital out to firewire. So im not sure whether you classify it as camcorder or TV footage. I captured the avi with Vegas 3.

As the olympics were in the US and i figured there was a chance of the NTSC-PAL conversion of the signal causing the problem (frame drops?), i have tried a lot of other local footage, with the same resulting problem. I have just loaded VirtualDub for the first time and i must say it looks like it might do a better job with that smart-deinterlacer plugin. I have a feeling that TMPGenc might be the problem. I can only hope so....

Thanks for your suggestion to try VirtualDub... ill let you know what happens.

kind regards,
blackout

[dizidave]

This is a long shot because i dont know exactly what ur doing.

I had problems with jerky video and the poblem was with DVD2avi......I had accidently got forced film on......have a look and see if thats the problem.

[dattrax]

I use AVIsynth Separatefields() function to split the fields and the selecteven() to get half the frames. Then its just a question of a bilinearresize() to 352x288 and thats it.

Jim

[Blackout]

Hi all,

thanks for your postings, i have read them all carefully. I havent been able to really find a solution to this problem, and i cant believe you all dont see this anamolity in everyday conversions.

Perhaps you are all only making VCDs of things that were shot to film , when i de-interlace and convert avis to mpeg1 i do not see any extra significant "jitter factor" added to the movement of things from film.

However when its from something obviously from video such as a sporting event or news broadcast, i get the "tick tick" factor in the picture that was never in the original. Its almost like the video picture now looks like it suffers from the kind of "ticking" that film exhibits. This makes sense as the VCD mpeg1 format is 25 fps, very close to film. But should this really be happening?

If you have ever created an mpeg1 from an analog video feed (avi) that is totally smooth like the original avi, please let us know how here@!

Many thanks,
Blackout

[AceYu]

I ran into the same problem encoding a realitavly slow moving pan, and it was even a cartoonish picture. I don't think that it is just the deinterlacing that is causing the problem (as I didn't have any) but a function of either frame rate conversions or the codex. I do know that deinterlacing will always be a problem with very fast action. Is it possible that you are inadverntaly capturing in NTSC (29ish FPS) and converting to PAL, that combined with the deinterlacing will cause a problem as fields are already being dropped when doing the frame rate conversion. I think that is what happened in my case, I accidently captured the footage in NTSC and encoded as PAL.

Later BRETT

[wway]

Blackout,

Try switching the field order of your source video.

If you're using TMPGEnc go to...Settings --> advanced --> field order.

wway

[Blackout]

i,

no wway like i mentioned earlier this is not a field order problem. I have tried the field order swap and its not related.

I have posted 2 mpeg examples of the problem at this address to hopefully help someone analyze this problem for me:

http://www.netspace.net.au/~darrenglen/

1:/ The mpeg1 has been converted from avi to mpeg1 de-interlace by Tmpgenc and is the file in question. Notice how the skaters "tick" around the ice at 25fps. The file is VCD compliant at 352x288, i just cranked up the bitrate to 2200 so it looks a bit more acceptable.

2:/ The mpeg2 was also converted by Tmpgenc and is still interlaced. Its at 704x576 so its more easily comparable with the mpeg1. As you can see the mpeg2 is a lot more blocky which is why im so keen to use mpeg1, but the skaters flow really smoothly round the ice as it hasnt been de-interlaced.

The best way to see these anamaloties is to burn a VCD and SVCD (i use CDRWs) and view them on a DVD player/TV but you can even see this issue in a media player.

if i had the room id upload the avi file but i hope this is enough to see the problem. Shouldnt a de-interlaced file look as smooth as an interlaced file? Any thoughts would be appreciated.

Many thanks,
blackout.

[pb]

I am downloading your file and will have look. I have been trying to encode DV AVI (PAL) from my camcorder to acceptable MPEG 1 or 2, interlaced/non-interlaced. This is basically what you are trying to do. I have found that MPEG2 looks better interlaced on a TV (as it should), but also with artifacts in motion/panning scenes. I cannot encode at a high enough bitrate (>6Mbps) as my DVD player only handles about 5Mbps, and in high motion/fast panning the artifacts still shoe up. I tried MPEG 1 deinterlaced with TMPG/CCE etc, and the artifacts are not as apparent (MPEG1 x/VCD is progressive). However, I do get smooth motion (as smooth as a hand held camcorder can be), but the background blurs in motion/panning, not too bad if you watch what is supposed to be the main action (pople etc).

I would like to know if deinterlacing can lookas smooth as interlaced, I suspect not. I used TMPG even-odd (Field) and 25fps, but there does not seem to be much difference between the settings. Using DVD2SVCD as an avi converter and CCE/smart deinterlace is not any better, in fcat CCE has less colour and more artifacts, even when using MPEG 1 and deinterlace.

People seem to confuse motion problems with field order or combing effects, not deinterlacing 25fps PAL files to view on PAL TV.

Anyway, I'll look at the clip and compare it to mine.

[Beni]

Hi Blackout,

I had the same problem as yours if the source is from digital handycam. But, if the source comes from analog handycam, the encoded PAL VCD plays smooth.

Anybody knows the answer?

Thanks.

[joeydlc]

Blackout, Beni,

Same problem here, all my source videos are captured from a D8 cam.

Beni, what card are you using to capture your analog videos?
And what software are you using to encode to VCD?

Thanks.

[Helpy Fairy]

My dear man and dear menlings trying to help man,

I will tell you the answer, it's not a rope, it's not a tree, it's not a snake,

IT'S AN ELEPHANT!!!



la la la

you're welcome!

[Beni]

Hi joeydlc,

I use an old MJPEG card to capture the analog and TMPEG as the encoder to VCD.

Yesterday, I captured a digital source with dazzle2. Try to make VCD from that source. I notice that this hardware encoder did not produce jerky pictures. It plays smooth, but has block artifacts.