XAVC Intra Class 300 4K UHD mezzanine for Broadcast Studio?

[FranceBB]

Hi,
I generally deal with Studios and send them XDCAM 1080i encodes, but lately I've been dealing with a few 4K UHD contents. This time, I gotta send an encode (from a 4K UHD ProRes master file) in XAVC Intra Class 300. They just told me "XAVC Intra Class 300", 3840 x 2160, 4:2:2, 500 Mbit/s CBR and 50fps. I have been searching on google over and over and it seems that the XAVC Intra Class 300 is:


Format XAVC intra (Class 300)
Level/Profile High 4:2:2 Profile @ Level 5.2
GOP I-frame only
Chroma Sampling 4:2:2
Bit Rate 500 Mbit/s
Constant Bit Rate Yes
Picture Size (active) 3840 x 2160
Aspect Ratio 16:9
Frame Rate 50fps
Scan Type Progressive
Bit depth 10 bit
Timecode in GOP header Not in use

Although I found these settings in some discussions in the forum, nothing "official".
By the way, if it's 10bit, shouldn't that be "High10" profile, like in x264?
Do you have any idea about this format? Because I don't have a clue...
And, most importantly, I don't have a clue about how to encode it, 'cause I don't know which codec/tool to use to encode once I pipe out footages from avisynth.

Thank you in advance.


EDIT 2021: It's now possible to encode in XAVC Intra Class 300 using x264 https://forum.doom9.org/showthread.php?t=182715

[poisondeathray]

Hi,
I generally deal with Studios and send them XDCAM 1080i encodes, but lately I've been dealing with a few 4K UHD contents. This time, I gotta send an encode (from a 4K UHD ProRes master file) in XAVC Intra Class 300. They just told me "XAVC Intra Class 300", 3840 x 2160, 4:2:2, 500 Mbit/s CBR and 50fps. I have been searching on google over and over and it seems that the XAVC Intra Class 300 is:


Format XAVC intra (Class 300)
Level/Profile High 4:2:2 Profile @ Level 5.2
GOP I-frame only
Chroma Sampling 4:2:2
Bit Rate 500 Mbit/s
Constant Bit Rate Yes
Picture Size (active) 3840 x 2160
Aspect Ratio 16:9
Frame Rate 50fps
Scan Type Progressive
Bit depth 10 bit
Timecode in GOP header Not in use

Although I found these settings in some discussions in the forum, nothing "official".
By the way, if it's 10bit, shouldn't that be "High10" profile, like in x264?
Do you have any idea about this format? Because I don't have a clue...
And, most importantly, I don't have a clue about how to encode it, 'cause I don't know which codec/tool to use to encode once I pipe out footages from avisynth.

Thank you in advance.

Yes that' s it. Also CAVLC, typically 8 track mono AES 24bit audio in MXF

You can use Adobe Media Encoder. There are presets for XAVC Intra Class300 and all the other official formats you're ever going to need to submit

x264 has some compatibilty hacks for 100,200, but not for 300


--avcintra-class <integer> Use compatibility hacks for AVC-Intra class
- 50, 100, 200

[GMJCZP]

FranceBB, I have no idea what this is but it seems that poisondeathray is on track: Here (http://www.xdcam-user.com/2016/02/xavc-class-480-what-is-it/) and Here (http://community.sony.com/t5/F5-F55/v8-0-XAVC-4k-480-codec/m-p/556662)

It looks like 480 is even better.

[FranceBB]

@poisondeathray
Got it. Tomorrow I'm gonna try with Adobe Media Encoder :)

@GMJCZP
Well, yes, it seems so, but if they ask for 300, I use 300. Generally in broadcasting everything is related to playout ports; probably their ports are only able to play XAVC Intra 300, which allows them to convert it live to HEVC for broadcasting. I bet it's similar to what they do now with Omneon playback ports and MPEG-2 1080i XDCAM. :)


I'll let you both know whether they'll accept the encoded file or not. :)

[kieranrk]

There has very recently been an x264 patch submitted but not merged yet which contains class 300.

[kolak]

FranceBB, I have no idea what this is but it seems that poisondeathray is on track: Here (http://www.xdcam-user.com/2016/02/xavc-class-480-what-is-it/) and Here (http://community.sony.com/t5/F5-F55/v8-0-XAVC-4k-480-codec/m-p/556662)

It looks like 480 is even better.

It's 300 class:

http://www.xavc-info.org/xavc/share/data/XAVC_Profiles_and_OperatingPoints_120_Amd1.pdf

high bitrate is due to the fact that file is 50p.

"The class number represents the approximate bitrate value at 29.97p"

[kolak]

Format XAVC intra (Class 300)
Level/Profile High 4:2:2 Profile @ Level 5.2


Although I found these settings in some discussions in the forum, nothing "official".
By the way, if it's 10bit, shouldn't that be "High10" profile, like in x264?

Thank you in advance.

It's High422 profile which covers 8/10bit at 4:2:0 and 4:2:2.
Hi10P is only for 4:2:0 sampling.

AME is good with XAVC handling.

[FranceBB]

It's High422 profile which covers 8/10bit at 4:2:0 and 4:2:2.
Hi10P is only for 4:2:0 sampling.

AME is good with XAVC handling.

Got it. It's encoding :)

http://i.imgur.com/MYNXgHD.png

Thanks for the link to the official PDF as well.
I'm waiting for the encode to finish.
Hopefully, the output from AME should be like this:

http://i.imgur.com/nfoVuQD.png

GOP N=1 'cause in intra profile all frames are intra, so there's no GOP (in order to avoid errors caused by motion-compensation, I assume).


EDIT: yes, encode finished, metadata are fine. It's 500 Mbit/s, with bars-note encoded at 367 Mbit/s which is fine.
I'm uploading it right now. I hope they'll accept it.

Thank you, everyone! :)

[kolak]

It should be fine as AME XAVC exporter is quite decent.
If your source is 10bit then avs route may not be optimal.
What are you feeding to AME?

[FranceBB]

My source it's a 4K Apple Pro Res, 10bit, decoded using Avisynth (FFMpegSource2 + 10bit hack + DitherTool for very very light denoise + light debanding -> Output lossless intermediate avi -> AME)

[kolak]

Is it good quality content made from 10bit+ masters?
In such a case you will be better feeding 10bit, e.g. by using vapoursynth and feed AME with virtual v210 AVI. Going to 8bit is a bit of compromise.
Well, it depends how you look at it.
1. At the end your master will be converted to 8bit compressed formats so fact that you denoised+dithered it makes is good for future use.
2. As service provider (I assume you are paid for the job) you want to work to high standards and follow good practice, so when you given 10bit master and delivery is also 10bit format you're expected to preserve 10bit.

[FranceBB]

Yes, you are right, but that's why I use the 10bit hack in ffms which is supposed to let me import 10bit materials in their native format and outputs to Stack16, then I can filter a bit at 16bit and then dither down to 10bit 4:2:2 to use AVI V210 as uncompressed lossless intermediate output file and feed AME.
As to vapoursynth, I've never tried it, although I heard many good things about it and probably one day I'll switch to it, unless avisynth will officially support High bit depth (no hack) and multithreading.

[kolak]

Ok, this is fine then. You just have to render v210 AVI first.

With vs you can use virtual file system and have "fake" v210 AVI which you can load to AME. It saves you time and disk space.

New avisynth also supports high bit depth without hacks.

Just be aware that you have to manually interpret field order in AME for interlaced sources as AVI doesn't store this info.

[FranceBB]

They said that everything was fine, except the colormatrix; they require BT2020, but I can't find any flag to change the colormatrix in AME. Picture (http://i.imgur.com/Bzt7ZWZ.png)

[poisondeathray]

Notice the specs officially say BT.709 for AVC-I 300 ...

AME only does BT.2020 for HEVC

But there is a workaround that involves AE
https://forums.adobe.com/thread/2346574

Or if you wait long enough maybe the x264 patch got approved ?

[kolak]

They said that everything was fine, except the colormatrix; they require BT2020, but I can't find any flag to change the colormatrix in AME. Picture (http://i.imgur.com/Bzt7ZWZ.png)


Well- in this case this is not anymore strict XAVC format as I don't think XAVC mentions Rec.2020 flagging.
Ask them which official tool can make such a file :)
Also if your master was done as Rec.709 you can't falsely flag it as Rec.2020. You would need to convert it to Rec.2020 so at the end it looks correct.
Their own spec say Rec.709, so they are telling you some crap. UHD doesn't have to be flagged as Rec.2020 if it wasn't made as Rec.2020. Rec.709 UHD file is "very" valid file.
Looks like it's one of those delivery places where 95% are juniors who have no clue what they are doing :)

[FranceBB]

Also if your master was done as Rec.709 you can't falsely flag it as Rec.2020.

It is Rec.709.


You would need to convert it to Rec.2020 so at the end it looks correct. UHD doesn't have to be flagged as Rec.2020 if it wasn't made as Rec.2020.

Exactly; luckily I can do it via Dither Tool.

Rec.709 UHD file is "very" valid file.

In fact their player accepts it and playback is fine, but they want Rec.2020 because they think it's "HDR", even though converting it from a native Rec.709 source it's like a placebo... But if they want a placebo, I shall give them a placebo...

[Gser]

It is Rec.709.



Exactly; luckily I can do it via Dither Tool.



In fact their player accepts it and playback is fine, but they want Rec.2020 because they think it's "HDR", even though converting it from a native Rec.709 source it's like a placebo... But if they want a placebo, I shall give them a placebo...

Hahaha in no way does Rec.2020 mean HDR.

[FranceBB]

I tried the latest EDIUS as well, but it seems it supports BT709 only 'cause it doesn't let me choose the colour matrix when I try to export to XAVC Intra Class 300 and, at default, it exports in BT709... Crap...

[kolak]

AME and Edius use official Sony component for XAVC export. They may have limited features, so check Sony Catalyst as suggested- if this doesn't allow Rec.2020 go back to your client and say that such a format simply doesn't exist and you can only simulate it. Get use to fact that some people (even in big companies) sometimes made up things as quite often they have no clue what they are doing. I have to deal with this constantly :)

Sony cameras had an update in 2016 to record XAVC as Rec.2020, but not sure if their XAVC plugins also have such a ability in latest version. Catalyst is your best bet as this is reference product when it comes to Sony formats.

update: Catalyst can do it.

[FranceBB]

Got it. Downloaded and installed Catalyst; I'm transcoding right now. Thanks.