Variable and Constant Frame Rates?


New member
Hello Everyone,

I would like to know if any version of Video Redo supports the changing of variable frame rates to constant frame rates and vise versa. If so, would a remux work for such a feature without the need to re encode the entire video?

Also, is .mpeg the only file extension that can remux without re encoding the entire video?

Thank you all in advance for your time.
Last edited:


Well-known member
It is my understanding that VRD (within limits) does not handle VFR.

If editing a video VRD recodes a few frames around an edit point.

When I think of "remux" I think of separating or combining the audio and video components of a file.
No recoding.


New member
@jmc Thank you for your reply. I'm just trying to take a screen capture that was captured to DVD spec, load it into Vegas Pro 17, without audio/video sync issues. I saw a post on the Vegas forms where someone used Handbrake to achieve this. The problem lies in that using this method will reencode the output file as mp4 or mkv. I do not want to re encode the file. I just want to repair the audio / video sync issue without the need to reencode. Any person on this form is welcome to reply, including jmc. Thank you all in advance for your time.


Well-known member
Well, "Quick Stream Fix" should resync the audio/video elements.
VFRate can cause many problems tho.


Senior Developer
Staff member
Unfortunately we can't handle VFR at all. Our internal code is heavily dependent on video frame timecodes having a single duration. When there is a big skip in the timecode it assumes there is an error and starts adding/removing frames to try and correct for it. At one point DanR was trying to make it possible to at least pass through a VFR file without editing so you could recode like you're asking for, but I think he ran into some insurmountable issues. I don't think we'll be able to support VFR video without massive change to the core code that makes VideoReDo function.


New member
@jmc , Thank you for your Quick Stream Fix suggestion. I actually tried that first. It made the audio WAY worse. It was very broken and choppy.

@Dan203 , Thank you for your honest feed back. Briefly, I did a screen capture as an mpeg (dvd spec I believe). I imported this capture into Vegas Pro 17. I quickly noticed I had not set my project settings to match those of my source file. Correcting this helped this audio/video sync issue quit a bit, BUT, it still was not exactly in sync. (I never rendered it out, just an observation within the preview window of the nle). I could still notice a slight lag. I ran the source file through Handbrake. It allows a vfr to be set as a constant, BUT, only if you preform a complete re encode. That re encode must be .mp4 or mkv. It defiantly helped the sync issue. Maybe just about as much or even a little more as my simple project settings I changed in Vegas Pro 17. The problem here is I do not want a compressed .mp4 or mkv file BEFORE my edits are complete. Therefore, I thought of video redo. Mainly because of it's ability to remux without another encode.

Any suggestion? Any way at all that Video Redo could help with my issue? It's worth noting that the capture program produces a perfect video where audio/video is in sync. Unfortunately, it does not permit edits like I can do in an NLE like Vegas Pro 17.

Also, is .mpeg the only file extension that can remux without re encoding the entire video? I had asked this question at the start of this thread. It just got overlooked. My first thought and best guess is yes. I think the answer is yes because of the very nature of how mpeg works. I've never heard of other formats being able to "adapt" to a remux EXCEPT maybe the avi container. I'd welcome your comments on this as well.

Here is the media info for the file I'm JUST syncing the audio for with NO additional edits. Yet, Video Redo still wants to force a complete 9 plus hour recode:

Complete name : C:\Users\Owner\Videos\Customer Raw Data\Mission Point Jubilee (2020)\Friday Night October 9th, 2020 - Ralph Sexton - Legacy Five\Friday October 9th, 2020 - Ralph Sexton - Legacy Five.mpg
Format : MPEG-PS
File size : 4.15 GiB
Duration : 2 h 20 min
Overall bit rate mode : Variable
Overall bit rate : 4 241 kb/s
ID : 224 (0xE0)
Format : MPEG Video
Format version : Version 2
Format profile : Main@High 1440
Format settings : BVOP
Format settings, BVOP : Yes
Format settings, Matrix : Default
Format settings, GOP : M=3, N=12
Duration : 2 h 20 min
Bit rate mode : Variable
Bit rate : 4 028 kb/s
Maximum bit rate : 9 000 kb/s
Width : 1 280 pixels
Height : 880 pixels
Display aspect ratio : 3:2
Frame rate : 59.940 (60000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.060
Time code of first frame : 00:00:00:00
Time code source : Group of pictures header
GOP, Open/Closed : Open
Stream size : 3.94 GiB (95%)
ID : 192 (0xC0)
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 2
Duration : 2 h 20 min
Bit rate mode : Constant
Bit rate : 128 kb/s
Channel(s) : 2 channels
Sampling rate : 48.0 kHz
Frame rate : 41.667 FPS (1152 SPF)
Compression mode : Lossy
Delay relative to video : -17 ms
Stream size : 128 MiB (3%)

Thanks again to all for your time. Suggestions?
Last edited:


Senior Developer
Staff member
No. We can edit MPEG-2, H.264 and HEVC without recoding.

I'm not actually sure why that file would force a recode. The resolution is odd, but that shouldn’t be an issue unless you're trying to crop or you set the max resolution in the profile to something lower.
Top Bottom