How to match previous RF setting?

General questions or discussion about HandBrake, Video and/or audio transcoding, trends etc.
Post Reply
Posts: 20
Joined: Sat Apr 03, 2021 1:05 pm

How to match previous RF setting?

Post by Bubbabob »

I want to encode a movie to as close to the movie's initial quality as possible. I'm encoding on low speed, and want to match the previous compression's RF setting. I have the app Mediainfo. Does this app show the movie's RF setting when originally compressed? If I set the RF at a lossier level I'll reduce the quality. If I set the number an at unnecessarily lossless level I'll blow up the file size.

The reason for going through this in the first place is I want to burn subtitles onto a previously compressed movie so that I can watch it on my tv's roku, which doesn't recognize forced subtitles.

Posts: 12
Joined: Thu Jun 03, 2021 3:22 pm

Re: How to match previous RF setting?

Post by az2020 »

If a video was encoded with handbrake, it stores the encoding details which mediainfo will report to you. But, other videos don't have this info.

I think anytime you reencode there will be loss. I'm a newbie, I don't know. But, if it were me and wanted to match the input filesize, I would set the video tab's preset slider to veryfast. I'd run this at different RF numbers to see which one produces a filesize I want. Then I'd slide the preset to veryslow or placebo, change the range from chapters to seconds (and tell it to encode a minute so you're not spending a lot of time experimenting). I'd see how that looks. If it's not good enough, I'd bump the RF number lower for better quality and larger filesize. I'd also experiment going to a higher RF to see if I notice degradation. Maybe you can get a smaller file and same quality.

I use placebo for my final/full encode. My understanding is that the quality improvement is so marginal that it's not worth it. People who do it are having a placebo sensation of "yeah, this is better." I do it at night while I sleep, so I don't care. I do think it makes a small improvement. But, processing time were important to me, I'd use veryslow instead. Placebo really slows it down. I agree it's not worth the negligble improvement. (My point is: the veryfast to placebo range of settings don't seem to affect the filesize. Or, not much. It's the RF that does it. If you test your filesizes quickly with veryfast, if you look at the result, they'll look horrible. Ignore that.).

Maybe there's a better way to burn subtitles. I'm new at this. But, that's the way I'd go at it if it were me.
Post Reply