Blu-ray bit rate

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Chainsaw

357 posts

Ultimate Geek

#99719 26-Mar-2012 10:34

Does anyone know what bitrate would be suitable for encoding my miniDV footage for a blu-ray disc so as not to notice any discernible difference in image quality?

I'm thinking maybe around 16-20 Mbs.

I know I'm not getting HD and all that, just trying to convert my tapes to a watchable format and as blu-rays fit more than DVD I'm using them.

Chainsaw

357 posts

Ultimate Geek

#600105 26-Mar-2012 10:52

I'll be encoding using AVC, not mpeg-2.

Chainsaw

357 posts

Ultimate Geek

#600569 27-Mar-2012 09:24

Have I stumped the geeks? ;)

Jaxson

8043 posts

Uber Geek

Trusted

#600582 27-Mar-2012 10:09

A big concern will be file size. If you're happy with that, then why not opt for the highest bitrate possible that produces a file that fits on a bluray drive?

Are you looking to play these files as a bluray or simply as a video file stored on a bluray disc?

stevenz

2802 posts

Uber Geek

#600583 27-Mar-2012 10:10

Given that a BluRay will fit around 25GB per-layer, you can probably set the bitrate as high as you like and not worry about it. Given that the source material isn't HD, then 5Kbps would be more than adequate. DVD quality rarely exceeds 8Mbps but that's using inferior compression. >10Mbps is more than enough for excellent quality 720p video.

Just try a few sample encodes and see what the output looks like. If the source material is interlaced, you'll need to de-interlace it while you're at it.

@KnightNZ

Jaxson

8043 posts

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#600585 27-Mar-2012 10:14

stevenz: If the source material is interlaced, you'll need to de-interlace it while you're at it.

+1 make sure you do a small sample file first to check before you commit.....

Chainsaw

357 posts

Ultimate Geek

#600694 27-Mar-2012 13:29

stevenz: Given that a BluRay will fit around 25GB per-layer, you can probably set the bitrate as high as you like and not worry about it. Given that the source material isn't HD, then 5Kbps would be more than adequate. DVD quality rarely exceeds 8Mbps but that's using inferior compression. >10Mbps is more than enough for excellent quality 720p video.

Just try a few sample encodes and see what the output looks like. If the source material is interlaced, you'll need to de-interlace it while you're at it.

This is to create blu-ray discs for a player, home movies.

Well I'm going to try to fit a couple (maybe even 3?) mini DV tapes on a (probably) 25GB disc, so there's a point of no return in the bitrate, I'd rather not just encode at the highest as it's bit of a waste of space in that regard.

I'm not that happy with 5Kbps DVDs, not bad, but not great, there's a definite quality loss from the source.

I'm thinking I'll have to buy a rewritable disc and do some trial and error.

The source is definitely interlaced - why de-interlace? I don't think Vegas can do 1080p, from memory.

Jaxson

8043 posts

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#600695 27-Mar-2012 13:33

Chainsaw: The source is definitely interlaced - why de-interlace?

Because you can't guarantee that your player will detect that it's interlaced and correct it for you. Better to deinterlace at the start, so the file you generate is how you want it to look.

http://upload.wikimedia.org/wikipedia/commons/1/19/Interlaced_video_frame_(car_wheel).jpg

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Chainsaw

357 posts

Ultimate Geek

#600697 27-Mar-2012 13:39

Yeah I know what interlacing is/does, but isn't lots of TV still interlaced, therefore no drama for me? I seem to recall pressing the info button on my remote and seeing 720i for the programme I'm watching. So does the player have to de-interlace it?

stevenz

2802 posts

Uber Geek

#600699 27-Mar-2012 13:42

Chainsaw: I'm not that happy with 5Kbps DVDs, not bad, but not great, there's a definite quality loss from the source.

DVDs @ 5Mbps look decidedly average as they use antiquated MPEG2 compression. AVC/h.264 gives somewhere in the region of twice the perceivable visual quality at the same bitrate. I'd be surprised if you could notice much difference between 5Mbps h.264 & MiniDV source material unless you were looking for it very closely.

@KnightNZ

Jaxson

8043 posts

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#600700 27-Mar-2012 13:43

It depends on what format you opt for and how the player sees the file. If it sees it as not requiring de interlacing then it wont touch it, it may just think you intended it to be that way.

Chainsaw

357 posts

Ultimate Geek

#600719 27-Mar-2012 14:21

stevenz:
DVDs @ 5Mbps look decidedly average as they use antiquated MPEG2 compression. AVC/h.264 gives somewhere in the region of twice the perceivable visual quality at the same bitrate. I'd be surprised if you could notice much difference between 5Mbps h.264 & MiniDV source material unless you were looking for it very closely.

Ah yeah, sorry, I thought you meant 5Kbs Mpeg-2. Indeed from what I've read AVC is twice the quality, or half the bitrate. So you reckon 5Mbps is about the tipping point then? Wow, I'd probably be able to fit 4 tapes on one 25GB disc then!

Chainsaw

357 posts

Ultimate Geek

#600721 27-Mar-2012 14:23

Jaxson: It depends on what format you opt for and how the player sees the file. If it sees it as not requiring de interlacing then it wont touch it, it may just think you intended it to be that way.

Sorry, don't quite follow that.
So the player will definitely de-interlace interlaced video? or does the TV do it? (I'm now assuming my LCD TV can't actually display interlaced material).

Chainsaw

357 posts

Ultimate Geek

#601402 28-Mar-2012 16:47

Went into Dick Smith to buy a disc or two - they don't have ANY blu-ray discs! Ayiyi.

Will try other places tonight.

Kiwipixter

246 posts

Master Geek

#601406 28-Mar-2012 16:53

Chainsaw: Went into Dick Smith to buy a disc or two - they don't have ANY blu-ray discs! Ayiyi.

Will try other places tonight.

PB Tech should have them, otherwise try online stores.