"Perfect" bitrate calculator for h.264 before wasting data?

Teagan wrote on 12/3/2020, 12:44 PM

Hi, I have been searching for a calculator to find this answer for 2 days now and I have found almost nothing that can guide me to the answer for this problem. Every one I have tried gives me an "acceptable quality" not best or highest bitrate before any higher will not show any more improvement in quality.

I have a lot of hi8 tapes that I have digitized to uncompressed and want to put as many as possible in AVC/h.264 720x480 4:3 29.97i on a 50GB blu ray with DVD Architect 7 but the problem is that I want to make it the most efficient as possible with the highest quality in h.264 that it can show, without diminishing returns on extra bitrate to waste space on a 50GB blu ray. I have about 40-50 files I want to fit but I don't want to encode in a higher bitrate if I don't have to, but can't afford to go overboard just to be safe (like 10Mb/s).

Is there a "perfect" bitrate for h.264 in 720x480 4:3 (640x480 essentially) for 29.97i?

Is there a calculator you can point me to that can calculate this? Highest quality bitrate right up until any more bitrate won't show any more improvement in quality?

Comments

Musicvid wrote on 12/3/2020, 7:57 PM

I have a lot of hi8 tapes that I have digitized to uncompressed and want to put as many as possible in AVC/h.264 720x480 4:3 29.97i on a 50GB blu ray with DVD Architect 7 but the problem is that I want to make it the most efficient as possible with the highest quality in h.264 that it can show, without diminishing returns on extra bitrate to waste space on a 50GB blu ray.

It's a good question.

Your source is standard definition analog interlaced 4:1:1, and that is the limiting factor, not your h264 settings, which are going to be overkill in almost any configuration. "Acceptable quality" is all you will get, if that, because your 4:2:0 encode will net you 4:1:0, and that's optimistic. We call it "blooming reds," and more bitrate unfortunately won't touch it.

For example, 2-4 Mbps is considered about optimal h264 variable bitrate for encoding from DVDs, which are digital 4:2:0. That is mathematically more than enough to glean every bit of signal from your hi8 captures, maybe go even less to smooth some of the grain in the shadows. You should be able to fit a lot on a 50GB BD. Personally I would not try to author a BluRay, but encode to x264 in HOS, Voukoder, or Handbrake, and just dump the files on your disc.

What I do with this stuff is play the original tape to my set-top DVD recorder, which has some hardware noise reduction, and be done with it. Capture / digitizing for editing really doesn't make it better. and lawd knows I've tried. If you go that route, NeatVideo comes highly recommended.

Less is usually more when encoding consumer analog tape video.