HandBrake

While reading up on TMPGENC, which seemed a likely candidate, it appears they've turned their attention to developing the PGMX file format, which is boasting Menus, Slideshows, etc.
https://tmpgenc.pegasys-inc.com/en/product/tpxc.html

If I'm reading correctly, TMPGENC will encode x264, but it is not mentioned for smart rendering or BD authoring.

The only thing I would produce at those bitrates are talking heads with static background.

I wonder what consumer authoring programs proactively support x264 without recompression, having looked through that article.
There is a broad disclaimer but no actual list, and my previous tries have been fruitless.

If you import x264 to BluRay authoring software, it will re-encode it to match its own requirements.
It will not smart render to BDAV/BDMV format (M@TS), at least I have seen no examples.

Handbrake is designed as a video encoder, not an editor.
I have tested Topaz, and it improves the appearance (but not accuracy) of upscaled video.
Based on experience, I would say "Probably not in the near future."

Try

RF encoding, the most efficient method, neither predicts nor controls files sizes, period. Your source will determine the outcome, and obviously your current source is different than your previous source. Raising your RF will reducing individual file size somewhat, with a corresponding loss of quali...

The link that @Rodeo gave seems relevant to that question.
Perhaps he can give some examples of using crf-max in concert with vbv-bufsize and vbv-maxrate to maintain more overall control.

One could expect some performance gains on 64 bit vs. 32 bit OS>

Specifying a high RF and then limiting the highest bandwidth peaks. More specifically, Lowering the bufsize to Match the maxrate Reduces the lookahead time. The Images in my Link illustrate the Effects on the Maximum, Average, and Minimum bitrates. As shown, I cannot adequately explain those effect...

Seeing where it's progressed, I have to agree with you.
indirect ≠ incorrect

It is difficult to state easily, and for that reason I had taken the unusual step of reporting my own comments for removal. I think understanding the concept of wagging the dog is best gained by looking at the images in the link I posted. It's also helpful to know that "maxrate" means &quo...

Setting vbv-bufsize and vbv-maxrate to the same value will effectively raise the minimum bitrate, which is what you are hinting at. However, you will have to experiment in RF mode, because it is a little unpredictable with different sources. See here for examples. https://forum.handbrake.fr/viewtopi...

Ritsuka wrote: ↑Thu Feb 25, 2021 8:38 pm Nightly builds have a 10bit pipeline (if you don't enable any filter on the filters tab), so it will better preserve the original video. 1.3.3 did 10 bit -> 8 bit -> 10 bit.

That is good to know!

I don't think you're ready to dive into BluRay Movie authoring and duplication just yet, but TMPGenc Authoring is widely used if you're curious.
You seem on your way to making something that will work in your disc player. Stick to formats that are as close to the original as possible, and carry on.

Handbrake has always been able to produce files that you can drop on a BD disc as data files and play in many players. Absolutely no question about that. However, the first sentence of your original post states: I want to burn backups of some of my original UHD Blu Ray movies on 50GB BD-R DL discs T...

With AVI files, simple concatenation in a Windows prompt will work as well as anything. To be clear, you can add your AVI files to Handbrake's Queue list and output a single MP4 file, as well.

Handbrake is not designed to encode compliant files for BluRay authoring.

1. Nope.
2. Maybe, depending on how they are originally encoded.

We are not MediaInfo support, but you must click the "View" Menu and pick a format to view the full MediaInfo readout.

I'm satisfied if i can get half the size of original file.

Then you would use the x265 software encoder in Handbrake. Half the size of QSV for "roughly" the same quality.

I tried QSV once, and never again. Yes, it is pretty fast.

They are video with dialogue/speech audio, so 48kHz are useless (wasted space).

Yes, somewhere in the neighborhood of a whopping 10 kb/s
Breathe out. 44.1 is not a specified Opus sample rate, so you have found a ..., typo

Audio for video is 48 Khz most of the time.