VideoHelp Forum - Video Conversion

Avidemux outputting at the wrong framerate

techmot — Sun, 07 Jun 2026 13:29:01 GMT

Does anyone know why when I've converted a video file in Avidemux where the framerate is 25fps, that I'm getting odd framerates like 22, 23 and 24.1?. As far as I know the programme should automatically output the framerate that the inputted video is set to.

Very good results : Compress H.264 to H.265 via ffmpeg, vmaf score 99.836

Gloster — Fri, 05 Jun 2026 16:47:43 GMT

Currently used Kubuntu 24.04. Wayland, ffmpeg 8.0

Did compress the video :

Video: h264, yuv420p(tv, bt709, progressive), 1280x720 [SAR 1:1 DAR 16:9], 11343 kb/s, 50 fps, 50 tbr, 90k tbn

to :
Video: hevc, yuv420p(tv, bt709, progressive), 1280x720 [SAR 1:1 DAR 16:9], 5075 kb/s, 50 fps, 50 tbr, 16k tbn

h.264 video-file size= 9GB. h.265 video-file size 3.7GB

VMAF score: 99.836461

the respective ffmpeg command as a script :

Code:

#!/bin/sh



for f in *.ts; do ffmpeg -y -i "$f" -map 0:v -map 0:a -vcodec libx265 -crf 16 -preset slow -vf nlmeans="1.6:7:5:3:3",unsharp="3:3:1.0" -c:a copy "$(basename "$f" .ts).mkv";done

A short description :
crf 16 = quality, less value higher quality
nlmeans = filter to reduce grain
unsharp = increase sharpness

Without the filter unsharp. I got a file size of 2.4GB (same video) and a vmaf score 95.6 .

For your information vmaf score of 100. no difference can be seen. 95.6, a good value.

Never reached this high vmaf score without "unsharp". I did decrease crf until I got a compressed file size < 1/2 source file, but the vmaf score max was 96-97.

Also I did compress with "unsharp" other videos with very equal results (vmaf score > 99.9)

I have a restriction : If I can not reduce the file size with crf 16, unsharp as given above to 1/2 of the source file-size. I decide for no compression.

Only to share my results.

Others who would like to share their results ?

Batch change Divx to Xvid (FourCC+Writing library+unpack bitstream)

SmurfRecorder — Sun, 31 May 2026 20:03:47 GMT

Hello. I'd like to change parameters of multiple AVI files at once to make them playable.
My current workflow on single file:
1. MPEG4Modifier - packed bitstream unpack
2. MPEG4Modifier change user data (Writing library from something like DivX503b2682p to XviD0069
3. Visual AVI FourCC Changer (https://sourceforge.net/projects/vsfccchanger/) - change fourCC - this works for all files

And I know I can do steps 1 and 3, e.g with FFMPEG with stream copy, but I'm not sure how to automatize step 2

this command did not change writing library:

Code:

ffmpeg -i input.avi -vtag XVID -bsf:v mpeg4_unpack_bframes -c:v copy -c:a copy output.avi

mu-dng-converter: Free GUI to convert DNG sequences to video (Time-lapse)

mu-files — Fri, 29 May 2026 15:58:15 GMT

I have an "allsky" camera that takes a DNG (raw) picture all day every 15s. That's 5760 raw captures per day. I wanted to convert these sequences of frames to a timelapse video, but couldn't find a simple utility to do it. So, I wrote my own. I just posted it on github to download (Windows, Mac, Linux, Raspberry Pi). Feedback is more than welcome.

https://github.com/mu-files/mu-image/blob/main/mu-dng-converter/README.md

[Attachment 92491 - Click to enlarge]

VirtualDub2 Now Refusing to Encode VP8/VP9

Hunterh — Mon, 25 May 2026 19:19:45 GMT

Well, that's it really. Until recently I encoded video in VP8, good quality and didn't take forever like VP9. When I try to do this using saved settings I get a message "Cannot start video compression. An invalid parameter was specified. (error code -6)" :mad:

I don't think anything changed since I use a saved settings profile. Possibly there was some change in originating video codec but these files are all run through an editor with "partial lossless" settings (splices in edits). Originating codec was dxtory. VLC reports all files as "(Codec: H264 - MPEG-4 AVC (part 10) (avc1))." x265 works but takes forever and the file size is several times larger.

I can't even get an idea of what "error code -6" means (what's the matter, did they use up all the numbers after 0?). I have tried switching around everything. I loaded up VirtualDub2, made no changes other than compressor VP8. A file from February renders without comment. One from March does not. Comparing the two files, they are seemingly formatted identically except the one that works has a pixel format of "yuvj420p (709:FR)" and the new one is "yuv420." Does that mess up VirtualDub2? Something I can do about it?

UPDATE:

Ok, I was testing some later raw files, they all passed. Then the current file passed. So it is something to do with the editor. No variables were selected. Output is to MP4. I don't care that much about the container as long as it's compatible and it works.

Anyway, I have a choice in container, as it turns out. I selected MKV (raw files happen to be MKV too) and suddenly VP8 is working again. No idea what changed.

Anyway, moral of the story is try to isolate the variables in your workflow. I was pretty fortunate that there were almost no variables and I have many files, older and newer to compare results against. This is an irritation to have to add yet another step to the workflow but eh, if it works it works.

There is no apparent reason why the older MP4s ran through VirtualDub2 and new ones will not.

Vapoursynth/Hybrid 24P Pull down from DVX100b. HELP DESPERATELY NEEDED!

amanwithamoviecamera — Fri, 22 May 2026 16:07:36 GMT

Hi all!

Made an account after years of lurking in desperate need of help. I've directed a music video and I'm getting round to finishing the edit, however we shot some extra material on my old Panasonic DVX100B. I shot in 24p mode and captured the raw .dv file. I've used Hybrid/Vapoursynth before for deinterlacing 60i to 60p, but I'm seriously hitting a brickwall trying to do a 24p pulldown.

Hybrid constantly crashes, and all my other ideas of getting this to work have failed. From rewrapping the .dv file to .avi so I can put the footage into Premiere and use it's 24p Pulldown. I also tried simply deinterlacing the footage to 29.97p but that ended up with stuttery footage.

If anyone has done this workflow before with 24p NTSC DV footage in Hybrid/Vapoursynth and could inform me how to do it, that'd be greatly appreciated. If it works smoothly as well, I may even credit you in the music video.

Many thanks!

B

video merge problem

ssuper2gg — Tue, 19 May 2026 13:45:19 GMT

Hi, I have a video merge problem. Two segments of videos, say A and B, a few seconds at the end of A and at the beginning of B are exactly the same. I want to merge them into a perfect video (cut off the duplicate part and play smoothly). I don't know the exact seconds of the duplicate part lasts. Is there any software or AI to solve the problem?;)