VFR to CFR conversion before editing

[jagabo]

result from post #26

[_Al_]

Been googling group of pictures GOP to get an understand of their meaning.
After reviewing the mediainfo, each of the codec's use different GOP structure.
Seem the voukodec codec uses 4 reference frames more the the MAGIX AVC rendered video and the drone source video format.
Would more reference frames ( assuming they are the I frames containing the full image) give better renders.
As the P frames only contain the difference in the next images from the previous reference frame.
Hope my understanding is correct.

Those reference frames are stored frames used for reference, so in theory, yes, more the better, but it depends on content and it also more reference frames means more overhead work for CPU.
Max number for those frames is here (stored frames):
https://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Levels
It all comes in a bunch with max bitrate, resolution,fps and that is bunched up as a regulation and it is called a level. So if you choose a level Main 4.0 in Voucoder you should have max 30fps for HD and 20000kbps for bitrate. But Voucoder uses x264, so you just select a profile. And particular profile would select all of it for you. It is a safe way with profile medium to keep all within regulations. For example profile Medium is a decent choice, compromise, and that would select all for you, number of reference frames etc., I would not worry about that, medium profile and forget it. For Youtube perhaps you can crank it up to profile Slow. You do not get a miracle changes if you change number of reference frames, only make it harder for decoding. And increasing storage space for those frames. If encoding HD, each stored frame suddenly is lots of space. In no way I'd let it be more than 4. There is some crazy things on web, where mostly for a cartoons you might see a video with 16 reference frames, but for a regular video I'd never do that.
If there is a choise for reference frames in Vegas again, just to be sane, for HD content never more than 4, for UHD it gets even more demanding, not sure if 4 would you get into trouble, if it is too much, you'd need also level at least 5.1 or 5.2(HD, UHD 60fps). But you try to play a level 5.1 on some older TV and it gets rejected, where only levels 4 are tolerated. So you can see now how it is all connected.

If it is for Youtube only, whatever it takes, whatever is tolerated, I'd guess Youtube might take even those extreme settings. But to increase ref frames is a wrong end to do it. Using higher bitrates or frames per second (60, record -> publish) or upload UHD instead of HD is the way to go.

Also x264 for HD content with about 20000kbits would not give you such a difference between frames, that is why people use encoders outside of Vegas , frame server or now perhaps even Voucoder if it is working and using x264 or other encoders. In Vegas you have to be generous with bitrate. Your video clip needs lots of bitrate because of constant pan, movement, encoder (cheap versions of reals ones that are for a sale) might struggle to come up with a reference or do not check quantizers deep enough to be on par and persistent, it might be set for a speed, and x264 might be much better.

[poisondeathray]

The default setting for voukoder libx264 is crf23 . Higher crf values lead to lower bitrate, lower quality, lower filesize. crf 23 is a bit too high IMO , I would use something lower . For general use I'd use 16-20 . If you want less loss you can go a bit lower. At crf 0 , it's lossless, but filesizes will be very large

But you can see when using libx264 the patterns and tree details are much more stable, there is less flicker, they don't change shape and details blurry/sharp/blurry/sharp

You can batch mp4fpsmod , and it can inplace edit if you want (e.g. process a folder of files without re-writing a copy of them)

[droner]

I just manually processed my new drone 2.7k 60fps VFR to 60000/1001 FFR with mp4fpsmod because there is some stutter in the original 60fpsVFR footage.
Hopefuly the frame rate adjust will improve it like it did with the 4k@30fps VFR from the drone.
I have been recording in 60fps VFR lately because the drone video looks smoother with recording fast movement over ground and panning.
I see that voukoder uses the vegas project settings, so for 1080p 29.97fps render output i just set that in vegas pro project settings.
I'm dropping the fps to 29.97 for more reliably viewing on friends HD TV.
With voukodec settings i chose H264 as my cpu has intelQSV and a geforce mx110 video card.
Hopefully the codec will use my cpu threads and graphics card for faster render. I will check it with task manager when rendering
With voukoder set to H264, the option shown are preset "medium" and CRF 17.
Should i bother with the advanced settings including rate control and frames options.
I'll give these setting a go.

[Sharc]

A VFR video that varies from 28.944 to 30.777 fps is essentially CFR. You can force it to CFR by remuxing to a container that doesn't support VFR (like AVI) at whatever frame rate you want, then remux back to MP4. You will retain every frame of the source, the conversion will be very fast, motion will be perfectly smooth (assuming the chosen frame rate matches the display rate), and there will be no quality loss. With ffmpeg:

ffmpeg -r 30000.0/1001.0 -i VFR.MP4 -c:v copy -an CFR.avi
ffmpeg -fflags +genpts -i CFR.AVI -c:v copy -an CFR.mp4
del CFR.AVI

The runtime may be slightly different than the original (depending on the frame rate chosen) but it probably doesn't matter with this type of video.

Nice, I must remember this trick.
How would I preserve the orientation flag of the original .mp4?

[jagabo]

How would I preserve the orientation flag of the original .mp4?

I believe it's "-metadata:s:v rotate=90" on the mp4 remux.

[Sharc]

How would I preserve the orientation flag of the original .mp4?

I believe it's "-metadata:v rotate=90" on the mp4 remux.

It works, thank you. So I can force the rotation, which is fine.
Is there a way with ffmpeg to pick the rotation flag from the source and transfer (copy) it automatically to the remuxed file?

[jagabo]

Is there a way with ffmpeg to pick the rotation flag from the source and transfer (copy) it automatically to the remuxed file?

One could get the rotation flag using ffprobe and pass it in the batch file as an environment variable. But it may also be possible to simply copy the metadata from the source video to the new video. I don't have time to try it out right now...

[Sharc]

Is there a way with ffmpeg to pick the rotation flag from the source and transfer (copy) it automatically to the remuxed file?

One could get the rotation flag using ffprobe and pass it in the batch file as an environment variable. But it may also be possible to simply copy the metadata from the source video to the new video. I don't have time to try it out right now...

Thanks, no problem, will try.

Edit: I just found that mp4fpsmod seems to do the trick as well.

[jagabo]

This will copy the rotation (and presumably other) metadata from the source mp4 file to the CFR mp4 file:

ffmpeg -r 30000.0/1001.0 -i input.mp4 -c:v copy -an CFR.avi
ffmpeg -i CFR.AVI -i input.mp4 -map 0:v -map_metadata:s:v 1:s:v -c:v copy -an -fflags +genpts CFR.mp4
del CFR.AVI

Also, I found that at least some videos with b-frames need to have the first "-fflags +genpts" removed or else they'll play jerky in some players.

[droner]

result from post #26

Thanks Jagabo.
Had a look at the video file
The Quality is the same as using mp4fpsmod.

[droner]

I ended up rendering a 2min clips with 3 different codecs.
MAGIX AVC with QSV took 7min and had that blurred to sharp frame.
MAGIX no QSV just cpu it took 2:20 min, still had sight burred to sharp frames.
Voukoder CRF 17 took 26min quality was better. ( no QSV, I think it's been disabled in the latest version of Voukoder)
Sony AVC no QSV took 2:20 min with good sharp frames.
My laptop only has a Intel i5 cpu and the Geforce MX 110 graphics card doesn't do GPU encoding.
So for speed and quality compromise i will be using the Sony codec.
If i cranked up the MAGIX codec to MAX quality and Bit rate the render was better but not as good as the Sony codec set to max bit rate.
Looks like CPU only does better rendering than QSV.

After searching the Vegas pro forum.
Other people are disappointed with the performance of the MAGIX codec.
They also find the old tried and proven Sony codec is better.

[Sharc]

This will copy the rotation (and presumably other) metadata from the source mp4 file to the CFR mp4 file:

ffmpeg -r 30000.0/1001.0 -i input.mp4 -c:v copy -an CFR.avi
ffmpeg -i CFR.AVI -i input.mp4 -map 0:v -map_metadata:s:v 1:s:v -c:v copy -an -fflags +genpts CFR.mp4
del CFR.AVI

Also, I found that at least some videos with b-frames need to have the first "-fflags +genpts" removed or else they'll play jerky in some players.

Great. Thank you!