General codec, video standards questions...

[j3flight]

What is that you want to do or learn about? Most of the codecs are used for media files that are in AVI (divX, Xvid) format, some new ones are PDTV (taken from HDTV sources) compressed into DivX and Xvid formats) if you want to view these then you need the right codecs for them or transcode them into mpeg 1 or 2 the same.
There is VCD (MPEG1), SVCD (MPEG2), KVCD, KSVCD, KDVD are other formats.

So many formats out there Real files, Quicktime and so on...

I'm just trying to understand what my options are for MPEG2 viewing. I live in the US and so most everything I record is telecined material (film sources). The decoder that ships with the PVR250 (Intervideo) does not do a good job of deinterlacing film sources. ("Film sources" includes any movie and almost every prime time show on television.) So, if i record something and play it back, because of the 3:2 telecine process (and the crappy decoder) I get playback that is fine for the most part, but anytime it does a slow horizontal pan i get video that looks "stuttery".

It does this because the decoder is just taking two fields and blending them together. This works fine on regular tv shows (that are 30fps) but it doesn't work for film sources which are 24 fps. Any vertical object in the picture goes sharp, blurry, sharp, blurry about 5 times per second if i use the intervideo codec (and some others).

DScaler is really smart and handles the telecined material perfectly and I get REALLY REALLY smooth motion on whatever I record.

All I'm really after are other choices. DScaler works great for me, but since it's in Beta, I thought there might be other codecs that are more mature that do a good job as well.

I'll try to take a sample of something I've recorded and host it. Maybe it'll make more sense then...

Jason

[Spartan]

This is a great thread.

Another question (since I've never really gotten into codecs before):

Since I use the MVP exclusively, it handles the MPEG2 decoding for me, so I don't need to worry about what I have installed, correct?

[j3flight]

To be honest, I don't know much about the MVP, but here is a shot...

The MVP, I think, just pulls the MPEG2 file across the network without any modification whatsoever just like it were a blob of data. So, what is getting to the MVP is an interlaced MPEG2 because that's what you originally recorded. And yes, the MVP does the decoding for you.

Your MVP is probably connected to your television with either composite or S-video, and both of those are sending a plain ole analog, interlaced video signal to your television. Your television is an interlaced device (assuming you have a regular tv, not HD) and the TV just spits it out just like it came in over the airwaves. So, in your case, there is no deinterlacing being done WHATSOEVER.

Here is my problem...
See, I use the S-video out from my ATI Radeon in my computer straight to a HD television. (Wishing i had component or DVI, but anyhow...)
The confusing part about my setup isn't the recording, it's the playback. I record in interlaced MPEG2 just like everyone else. So, when I playback the MPEG2 on my monitor, it needs to be de-interlaced or I get little scanlines all throughout the picture during movement. Like this:
http://www.100fps.com/distortion2.jpg

If I want to watch the video on my television, I get this funky situation:
The MPEG2 is deinterlaced to be shown to the computer monitor, the TV-out function of my video card re-interlaces it again so it can be output over S-video, and then my HDTV accepts the interlaced NTSC signal and de-interlaces it so it shows a progressive image. Wow, I know! But, believe it or not, the quality is pretty darn good and it is difficult to tell the difference between a timeshifted recording using GB-PVR and the actual cable feed into the TV. It took some time to get the colors adjusted just right, but I'm really impressed with it.

I have tried not doing any deinterlacing on the video at all (ffdshow allows you to turn it off) thinking that skipping that step would avoid some quality loss, but I think there are timing issues associated with that (refresh rates, etc) and it just doesn't look right on my TV - motion gets jerky - plus it looks like crap on my monitor.

Anyway, I have a video file that shows exactly the type of stuttering I'm talking about. The movie is Sgt. Bilko, recorded from cable TV a while back (so quality isn't quite as good as I have it now, but you'll get the idea).
http://www.cromes.net/junk/BilkoReallyShort.mpg (20MB!)

Keep an eye on the soldiers in the background who are standing still while the camera follows the main actor. See how they go sharp, blurry, sharp, blurry? If they don't do that, then you're using a codec that does a good job of inverse telecine (like DScaler). If they do, you're probably using the Intervideo codec or something similar and you'll understand what I've been talking about.

Jason

EDIT: Be aware that some players use their own codec - Media Player Classic will use it's built in lib2mpeg which can do a decent job depending on your settings. WinTV2000 always uses the Intervideo codec (I think), so try that if you have it.

[Tulex]

All I can say is that with intervideo, I don't get an in and out blurry thing, but horizontal lines. I don't get this with anything else I've captured or d/led from online, even low quality stuff. Also, it looks the same in GB or media player.

[j3flight]

Well, what you're watching is a direct capture from a PVR 250. I didn't modify the video whatsoever, except for chopping out that small portion.

It is NTSC video, 29.97fps. Film source. Telecined because it was a movie. Not sure on the bitrate, pretty high VBR though.

Jason

[Tulex]

So you are saying that on the pc, it's fine, but not on the tv. I only looked at it on my pc. With the lines, on my pc, I would have thought it was the actual capture that had a problem.

[j3flight]

No, i'm saying that it'll look bad on both. Pretty much whatever I get on screen is what I get on my TV - as far as interlacing/motion goes. That surprises me somewhat, but it seems to be consistent.

With an absolute barebones install of XP + the hauppauge/intervideo stuff, I can guarantee that film captures will do the blurry/sharp/blurry thing.

Tulex: do you get lines constantly throughout the video, or only a few times per second? Kind of a pulsing?

Jason

[Tulex]

They are more or less constant, but more noticeable with rapid movement. Like, there are poles that whip by when the view spins. The pole is like a stack of lines that don't match up. When I use moonlight? in a window, I get what you are saying, the blurriness in and out matches the beat of his steps. In full screen, I get the lines, but they match up better.

[Tulex]

I only have one drive set up. I don't have it partitioned. Why does this matter?

[j3flight]

Does matter, XP Page File has to swap out to the same drive you have all your programs installed and the OS, then the biggest program is the MFT (master file table) think of that a list of all you files in a catalog, if that gets to large over 99% then it gets fragment and can slow down things and it also works with the page file. I got 5 HDDS in my box, but each one is doing it's own thing. The biggest is for Recorded TV and I don't have all they video problems with playback.

Unless you're running physically separate disks (which it sounds like you are) then it really doesn't make a huge difference. I agree that separating the partitions does help with fragmentation, but the problems I'm talking about have nothing to do with HDD issues. My disk has almost zero activity when recording or playing back.

Jason