off center picture; framerate discrepancy FLV->MKV

[spiritgumm]

I used Stream Transport to record an online video I couldnt otherwise get. The resulting FLV file looks/sounds great in VLC, but the picture is off center in Media Player (see image). Can I fix this?

I wanted to repack the FLV into MKV, so I extracted the files and muxed with mkvtoolnix. I noticed the framerate changed 29.97 -> 30.303. Setting the framerate manually while muxing had no effect. Any ideas why this happened and if I should be concerned?
Also, the picture (from the MKV) is of course still off center in Media Player.

[El Heggunte]

First, please open the FLV in VirtualDub and tell us what it looks like.
I've seen at least one downloaded FLV which was cropped during playback through DirectShow, but was shown in "full-height" with VirtualDub.

Just for the notes, FLVs are generally muxed with weird video timestamps, which makes them be often misdetected as Variable-Frame-Rate OR @ 1000 fps

[jagabo]

Try a different DirectShow decoder for the video codec.

[spiritgumm]

I didnt state this originally, but I want to repack the FLV into MKV losslessly (no re-encoding).

The thing is, the video plays fine in VLC. Other FLV/MKV (although not all) will play correctly in MediaPlayer. So rather than change decoders for MediaPlayer, is there a way to make the file more generically and perfectly playable?

I initially looked for a generic FLV file fixer without luck. Then tried Vdub, but couldnt open the FLV or the separated video file (h264). I added a Vdub plugin for MKV but it wouldnt open because of the AAC audio. I could open the MKV in Avidemux, but simply re-copying it didnt fix the video issues for MediaPlayer (and it also introduced some hesitancy in the video playback).
At that point, I got tired of researching and posted here. There doesnt seem to be any way to contact Stream Transport for help.

Another solution would be figuring out another method to DL the original video (although I've tried all the usual methods).

[jagabo]

The problem isn't in stream transport, VirtualDub, AviDemux, the FLV file or the remuxed MKV file. The problem is the DirectShow h.264 decoder that's being used. It doesn't understand that the source has an active picture size (the part that's supposed to be displayed) smaller than the mod 16 frame size. VLC uses its own internal h.264 decoder so it's not a problem there.

[spiritgumm]

so downloading with another program wouldnt change this? I thought Stream Transport was screen capturing and thus making it's own frame size. If not, is the only other solution to re-encode to ensure perfect playback ?

[jagabo]

Stream Transport downloads the file(s) from the server. It doesn't reencode.

[spiritgumm]

I updated Mediainfo and now the FPS reads as 29.97.
Went thru the list of Directshow options in MPC playback; was using "System Default," finally worked with "Overlay Mixer." Thanks for the heads up about it.