Does WMR convert VFR ->CFR?

KeyMs92 · #1 10-18-2011, 05:54 PM

Hi,

A few weeks ago I tried the program 'Jaksta' and noticed that in constrast with WM Recorder, it recorded streams in a variable framerate. I was wondering if it's indeed the case that WMR records streams in a constant framerate. If so, does it then actually convert (dropping/adding frames) to constant framerate or does it take the variable framerate as being constant (like e.g. Vdub does)? It seems to me the former, because audio/video remain perfectly in sync in the recording, which often doesn't happen when there's no conversion.
I hope someone can help me out

#2 10-19-2011, 11:59 AM

WM Recorder and Jaksta should record video as is, so video with the variable frame rate should stay with VFR and video with the constant frame rate should stay with CFR.

WM Recorder seems to be very good at syncing audio and video tracks, but I'm not sure it has something to do with CFR.

Have you tested both programs on the same source? What is the link to the web-page with the video where you have discrepancies?

KeyMs92 · #3 10-19-2011, 03:09 PM

I'm a recording a BBC radio 5 live stream. I've tried both Jaksta and WM Recorder two times.

It's interesting you say that they should both record in VFR if the source is VFR. When I mux the video stream from the flv file and open it in VirtualDub (I have to because the flv container makes Vdub crash) I must set both WMR recordings to exactly 25fps to make the audio sync and the Jaksta recordings to 25.00x. (Indicating that the WMR records in CFR.)

I've uploaded the timecode files, extracted by FLVExtract from the original recordings. Maybe you can interpret the data in some way.

http://www.4shared.com/file/ApmVQR7T/timecodes.html