Encoding Video for Blu-Ray using H264/AVC

[mp3dom]

If you add the transfer characteristics/color primaries/colormatrix (to bt709) you also need (or, it's better) to add also the videoformat 'ntsc' if you're encoding at 30/60/23.98/24 fps. The pro-encoders do this (you can not add the information, but if you add them also the NTSC video format is specified). I haven't tested it, but probably for 25/50 fps the 'pal' video format is added.

[Sagittaire]

Originally Posted by laserfan

Thanks shon3i for the charts.

Question: I've been using --keyint 24 and 15000/15000 for all "BD"-on-DVD work, and given my bitrates are typically in the low 3500-7000 range should I really be using --keyint 48 instead to minimize "pulsing" at GOP changes?

yes will work for all scenario ... and GOP 48 vs GOP 24 produce ~2% better compression efficiency.

[laserfan]

Originally Posted by Sagittaire

... and GOP 48 vs GOP 24 produce ~2% better compression efficiency.

Thanks a lot for this--while I'm unlikely to notice this type of improvement, I have changed my default to 48 keyint and the results work in my player!

[MadMonkey57]

Originally Posted by MadMonkey57

And what about --min-keyint ? Does it have to be set with regards to --keyint or x264 default (auto) is blu ray compliant ?

Anyone ?

[rack04]

Originally Posted by MadMonkey57

Anyone ?

I don't know whether it needs to be set but I error on the side of caution. If I know that something needs to be set I don't rely of a default/preset/tune to set it for me.

[MadMonkey57]

I agree. That's why I always set --min-key-int to 2 (which most of us use) for my 23.976p encodes.

Still I am wondering for other encodes especially 50p and 25i...

[shon3i]

Just leave default x264 setting. From revision r1537 x264 automaticly calculate min-keyint with keyint/10. so with Shot GOP min-keyint will be 2 with long 4, wich is just fine.

btw i am currently work to complete this stuff, be patient few more days with all need explanations

[MadMonkey57]

All right.Thanks.

[Sharc]

Will --fake-interlaced produce blu-ray compliant 576 encodes
of a progressive PAL DVD source? Or do I have to set --tff?

[kieranrk]

Originally Posted by Sharc

Will --fake-interlaced produce blu-ray compliant 576 encodes
of a progressive PAL DVD source? Or do I have to set --tff?

--fake-interlaced should work. You will need --pic-struct of course.

[Sharc]

Thanks, and for reminding me of the --pic-struct.

[kieranrk]

I wrote a simple guide for the most common Blu-Ray scenarios. See my sig.

[Lyris]

Much appreciated, Kieran, good to know my tests have been BD compliant.

Can you advise me (and others) here - are the following encode settings also good?

16:9 "NTSC" 720x480 Secondary Video stream
I know the max bit rate here is quite conservative, that is my intention.

x264 --bitrate 3000 --pass 1 --preset veryslow --weightp 0 --bframes 3 --me umh --merange 24 --partitions all
--subme 10 --trellis 2 --rc-lookahead 60 --direct auto --ref 6 --nal-hrd vbr --vbv-maxrate 4000 --vbv-bufsize 6000
--level 3.2 --keyint 24 --b-pyramid strict --slices 1 --aud --colorprim "smpte170m" --transfer "smpte170m"
--colormatrix "smpte170m" --sar 40:33 infile.avs -o outfile.avc

x264 --bitrate 3000 --pass 2 --preset veryslow --weightp 0 --bframes 3 --me umh --merange 24 --partitions all
--subme 10 --trellis 2 --rc-lookahead 60 --direct auto --ref 6 --nal-hrd vbr --vbv-maxrate 4000 --vbv-bufsize 6000
--level 3.2 --keyint 24 --b-pyramid strict --slices 1 --aud --colorprim "smpte170m" --transfer "smpte170m"
--colormatrix "smpte170m" --sar 40:33 infile.avs -o outfile.avc

Standard Definition Primary video (for bonus features, etc)
I gather that since 23.976fps is not allowed for SD material on BD, we need to add some sort of 3:2 pulldown flag. Is the way X264 does this BD compliant?

[shon3i]

Can you advise me (and others) here - are the following encode settings also good?

Everything look good to me. Just advice about vbv, keep both value near each other. You can use --keyint 48 aslo.

Standard Definition Primary video (for bonus features, etc)
I gather that since 23.976fps is not allowed for SD material on BD, we need to add some sort of 3:2 pulldown flag. Is the way X264 does this BD compliant?

Yes but need to be interlaced aslo. If you sourtce is 23.976p you can use fake interlaced with 3:2 pulldown.

[kieranrk]

Originally Posted by shon3i

Yes but need to be interlaced aslo. If you sourtce is 23.976p you can use fake interlaced with 3:2 pulldown.

I'm not 100% sure that will pass some verifiers. It's a very strict interpretation of the spec.

[shon3i]

Originally Posted by kieranrk

I'm not 100% sure that will pass some verifiers. It's a very strict interpretation of the spec.

As long is 29.97i should pass, but if someone send me a sample i can verify

EDIT: i create my own 23.976p sample, encoded using fake interlaced and puldown 32 to produce 29.97i stream, but this file will not pass mui generator.

[Blue_MiSfit]

Maybe just forget about fake interlaced and only use pulldown??

Derek

[mp3dom]

23.98p to 29.97i via 3:2 pulldown is allowed. Probably the fake-interlaced is not needed in this case.

[shon3i]

Originally Posted by Blue_MiSfit

Maybe just forget about fake interlaced and only use pulldown??

Derek

it's ok for secondary video, but for primary 720x480 must be interlaced (or fake interlaced)

[mp3dom]

Doesn't the pulldown already flag the stream as interlaced?