Good bitrate to encode a 720P 59.94 fps VHS transfer for Blu-Ray?

[brassplyer]

Captured some VHS video, deinterlaced to 59.94, cleaned it with NeatVideo, upscaled it to a 1280x720 picture (960x720 in a 1280x720 pillarboxed frame) to transfer to Blu-Ray.

DVD Architect Studio default is 18MBPS, what bitrate would you consider overkill for this kind of project?

Thanks.

[jagabo]

6276.4 Mb/s.

But seriously, encode a representative segment with x264 at CRF=12. Then use that bitrate -- if your forced into bitrate encoding.

[brassplyer]

6276.4 Mb/s.

But seriously, encode a representative segment with x264 at CRF=12. Then use that bitrate -- if your forced into bitrate encoding.

What other kind of encoding is there? Isn't all encoding done at a particular bitrate?

[manono]

Isn't all encoding done at a particular bitrate?

No. There's quality-based encoding which encodes for a requested quality and the bitrate needed to achieve that quality isn't known in advance. Like the CRF 12 jagabo suggested.

[brassplyer]

Isn't all encoding done at a particular bitrate?

No. There's quality-based encoding which encodes for a requested quality and the bitrate needed to achieve that quality isn't known in advance. Like the CRF 12 jagabo suggested.

I've seen that with Handbrake, but why is that superior to going for a particular bitrate?

[manono]

I've seen that with Handbrake, but why is that superior to going for a particular bitrate?

Did anyone claim it was superior? It's faster, for sure, since you only run a single pass. And if the filesize doesn't matter you're guaranteed a certain quality. You asked what bitrate should be chosen. The answer is the bitrate for the quality you want. If you know what quality you want and do a test encode, from that you can deduce the bitrate you want. Or just do a CRF encode to begin with. I mean, how is there a reasonable answer for, "what bitrate would you consider overkill for this kind of project?"

6276.4 Mb/s.

[jagabo]

With bitrate based encoding you know what the file size will be but you don't know the quality. With quality based encoding you know what the quality will be but you don't know the file size. Use bitrate based encoding when you need a particular file size. Use quality based encoding when you want a specific quality.

[brassplyer]

I've seen that with Handbrake, but why is that superior to going for a particular bitrate?

Did anyone claim it was superior?

By implication when he said:

if your forced into bitrate encoding

[brassplyer]

With bitrate based encoding you know what the file size will be but you don't know the quality. With quality based encoding you know what the quality will be but you don't know the file size. Use bitrate based encoding when you need a particular file size. Use quality based encoding when you want a specific quality.

It seems it's still an abstract number, unless there's an app that automatically gives you a screen shot "here's what it will look like at this quality"

[jagabo]

With bitrate based encoding you know what the file size will be but you don't know the quality. With quality based encoding you know what the quality will be but you don't know the file size. Use bitrate based encoding when you need a particular file size. Use quality based encoding when you want a specific quality.

It seems it's still an abstract number, unless there's an app that automatically gives you a screen shot "here's what it will look like at this quality"

A particular CRF value always gives the same quality (relative to the source -- ie, it can't make a poor source better) no matter what video you're encoding. Once you've run a few test encodes you'll get an idea of what CRF value gives the quality you want. Think of the CRF value as how much detail is thrown away. CRF=0 is literally lossless (with a YV12 source, and not Blu-ray compliant). CRF=12 is nearly identical to the source (and about what you see with a good Blu-ray disc). You will see minor differences looking at enlarged still frames but you would be hard pressed to say which is the original and which is the encoded video. CRF=18 is very close to the source when watched at normal playback speeds. If you look at enlarged still frames you'll see some small detail loss. You may occasionally see some posterization artifacts in dark grainy areas (because some of the grain is gone). CRF=24 is about like many highly compressed videos you might download off the internet or a good video at Youtube.

If you encode a video in CRF mode and it gives X bitrate, then encode the source again in two pass VBR mode using that same X bitrate, the two videos will be nearly identical.