Does changing video frame rate decrease quality?.

[Felow]

Obsolete

[jagabo]

to remedy this problem I thought of changing the frame rate of all my videos to a constant 29.97

That's a bad idea. If you encode a 23.976 fps video at 29.97 fps you will end up with jerky motion.

If you want to mix frame rates within a single video file you need to flag the frame rate as variable and include time codes for every frame.

[SaurusX]

x264 will allocate more bits per frame for lower frame rate videos.

But in speaking about merging videos of differing frame rates, I wouldn't do it. What situation do you have where that is necessary?

[Felow]

x264 will allocate more bits per frame for lower frame rate videos.

But in speaking about merging videos of differing frame rates, I wouldn't do it. What situation do you have where that is necessary?

I use HEVC.

I merge videos to make compilations so they're are from different sources and have different frame rates.

[Felow]

obsolete

[Cornucopia]

BTW, @Felow, using that kind of font highlight color in your text make it appear (at least on the stock VH Blue theme) almost invisible. If you want to emphasize, I recommend you just use BOLD.

Agree, it is rarely a good idea to merge clips of different framerates. VFR is the devil's spawn.
If it were me and I had to do it (because of them both being in a newly edited piece or something), I'd Telecine the 23.976 to 29.97 (actually usually 59.94 because interlace), especially as that is already commonly done to convert, thus people are used to it, and it is fairly easily reverseable.

Scott

[Felow]

BTW, @Felow, using that kind of font highlight color in your text make it appear (at least on the stock VH Blue theme) almost invisible. If you want to emphasize, I recommend you just use BOLD.

Agree, it is rarely a good idea to merge clips of different framerates. VFR is the devil's spawn.
If it were me and I had to do it (because of them both being in a newly edited piece or something), I'd Telecine the 23.976 to 29.97 (actually usually 59.94 because interlace), especially as that is already commonly done to convert, thus people are used to it, and it is fairly easily reverseable.

Scott

Alright.

And do you have any idea why merging 25 and 29.97 doesn't result in artifacts?.

[Cornucopia]

No, it SHOULD have artifacts (in the form of jerkiness) also, unless it is properly automatically changing it to VFR (I doubt it).
or
Perhaps that form of framerate change is not something you're sensitive to, compared to a Telecine change (depends on your region, and your training, and your individual sensitivity). 25 combined with 29.97 when properly done only shifts once at the boundary between the 2.

Scott

[Felow]

Update: Changing the framerate from 23.976 to 29.97 while encoding solved the problem. Now I can merge videos without having artifacts, thanks.

[sneaker]

Just for the record: what HEVC encoder are you using? x265, Nvidia NVENC, AMD VCE or Intel QuickSync? (I think those are all offered by HandBrake/VidCoder.)

[Felow]

Just for the record: what HEVC encoder are you using? x265, Nvidia NVENC, AMD VCE or Intel QuickSync? (I think those are all offered by HandBrake/VidCoder.)

X265 10-bit, CRF 23 Preset Slow.