Weird Glitch In Some H.264 Videos

[LaJoN]

Well, I've asked around and tried every suggestion I recieved in the forums I frequent about this, and nothing has fixed it. So here I am at Doom9, where I hope someone will know what's going on.

On the right side of the video there is a strip going from top to bottom that's only a few pixels wide. In some videos, it's only slightly visible because it just seems missaligned with the rest of the video, even though it displays the same colors and all that. Other videos you won't see it at all, yet in others it will display black/white colors randomly in the strip.

I've tried all the H.264 decoders out there and all produce the same problem. There is only ONE way to make it go away so far as I've discovered and that's to drag the border of the video player I'm using away from the frame of the video so that it adds a sort of letterboxing between the picture and the border of the player.. Otherwise, it'll be there while viewing it windowed or fullscreen. Also, all players produce the same glitch that I have installed on my computer (VLC, MPC, WMP).

Here are two screencaps I grabbed using printscreen while viewing the videos at fullscreen. Using the "Screencap" function in any of the players I use don't capture the glitch. I've sent these two videos to friends of mine and the glitch doesn't appear for them, so it's not in the videos themselves.

http://img261.imageshack.us/img261/251/funkybug2fl6.th.jpg (http://img261.imageshack.us/my.php?image=funkybug2fl6.jpg) http://img220.imageshack.us/img220/9799/funkybugil8.th.jpg (http://img220.imageshack.us/my.php?image=funkybugil8.jpg)

Also, I've fraps me viewing the video to give you a better picture as to what it looks like. Don't mind the quality, that's just how it comes out when you fraps a video you're watching. Also linked is the video itself.

Mediafire Link (http://www.mediafire.com/?1zz1ommwmij) (Fraps Capture of Video viewing w/ glitch)
Mediafire Link (http://www.mediafire.com/?1qwytjmyjmu) (Actual Video)

My videocard is a GeForce 7800GTX PCI-E, and I've tried a bunch of different drivers for it to see if that was the problem as well, but nothing changed. I haven't added any new hardware to my computer in while, but it's just started showing up recently. I just did a reformat of my computer and it's still there. Stripped out all my codecs and started putting them in one by one but it still had the glitch the moment H.264 videos were viewable.

Any help solving this would be much appreciated! It's so annoying to see weird colors on the right side of videos I watch in fullscreen. :(

Thankyou!

[Sharktooth]

900 is not mod 16. Resize to a mod 16 res (896) to be sure the problem doesnt come from an avisynth filter or something that requires mod 16 resolutions.
Also crop away the black borders, they interfere with the compression.
However i dont understand why you upsized the original video(s) to a higer res. it's useless and it's a waste of disk space.
oh... and your avatar is ugly ;) (joking)

[check]

best practice when encoding is to fully crop off all black borders and then to resize to mod16 dimensions as per above.

[LaJoN]

Guys. Those are print screens of me viewing it full screen. The video is only 640x480, and my desktop rez is 1440x900 on a widescreen monitor. Taking screencaps from the video player didn't show the glitch, so I had to use that method.

Did anyone even read my post? ;[

[foxyshadis]

Did you try switching renderers? Because you've basically ruled out a decoding problem completely, as well as a single-player problem, so the issue probably lies in the video driver, hardware, or renderer (or the interaction between the three). I'd try overlay and all the different VMR modes to see if any difference crops up between them.

[LaJoN]

Did you try switching renderers? Because you've basically ruled out a decoding problem completely, as well as a single-player problem, so the issue probably lies in the video driver, hardware, or renderer (or the interaction between the three). I'd try overlay and all the different VMR modes to see if any difference crops up between them.

I used all the one's that were an option in Media Player Classic:

Overlay Mixer
VMR7 (Windowed)
VMR9 (Windowed)
VMR7 (Renderless)
VMR9 (Renderless)
Haali's Video Renderer

None of them got rid of the problem. Also, I just removed my video drivers and watched the videos again. Glitch still there.

[DarkZell666]

I can see the problem in the original video already, so dunno what went wrong during encoding, but it's definately NOT a playback problem (playback of H.264 in mplayer has never caused any problems to me).

[LaJoN]

I can see the problem in the original video already, so dunno what went wrong during encoding, but it's definately NOT a playback problem (playback of H.264 in mplayer has never caused any problems to me).

I just encoded a video with XviD and the problem is there too. What could be causing this problem? I'm using Gordian Knot 0.35.0 to encode, and here are the codecs I'm using with it:

Koepi XviD-1.1.0-30122005
x264 50 svn-565, build Sep 22 2006

These encodes are from VOBs. I run it through DGIndex, open it up, set it to 640x480, auto crop, set the bitrates to determine filesize, save, pick deinterlacing method, setup audio/video bitrate settings, and then encode. Could there be a problem in the codec settings that would cause this, or maybe Gordian Knot is to fault? I don't know.

I'd really need to get this problem fixed as soon as possible as I do a lot of encoding for a subtitling group and I don't know if I can be doing that with a problem like this.

[LaJoN]

This is not a bump of my own thread. Just wanted you guys to know that I've figured out what the problem is. You can deleted the thread if you'd like, or keep it around incase anyone else comes across the problem.

Did a LOT of reading and research once I found out that other people were seeing the same glitch I was, which told me that it happened during the encoding process. Went over to the Gordian Knot forum and one of the sections in the "Resolutions, Aspect Ratios And The ITU-R BT.601 Standard" caught my eye:

"Using other crop-values can create strange artifacts at the end of lines/frames. Crop(3,0,716,480), for example, is NOT acceptable as it means you have split a pixel pair! The values are stored in AVIsynth in pairs (or 2x2 matrixes in the case of YV12), and they should never be separated."

Went back and made sure to crop according to that post and the problem dissappeared. Thanks for the help guys.

[Manao]

Add the following :

"Never use a end resolution that isn't dividable by at least 8 if you plan to encode with AVISynth, because it's more than likely that you have a buggy YV12 VFW decoder ( the one that comes with XviD is buggy, for example, and is used with x264.exe when opening avisynth scripts ), which doesn't handle correctly anything than isn't dividable by 8 ( the chroma gets shifted by a fourth of the picture, horizontally )"

[LaJoN]

Add the following :

"Never use a end resolution that isn't dividable by at least 8 if you plan to encode with AVISynth, because it's more than likely that you have a buggy YV12 VFW decoder ( the one that comes with XviD is buggy, for example, and is used with x264.exe when opening avisynth scripts ), which doesn't handle correctly anything than isn't dividable by 8 ( the chroma gets shifted by a fourth of the picture, horizontally )"

Indeed. At least I knew not to do that. :sly: