BD Rebuilder Beta - Bug Reports Only

[jdobbs]

Originally Posted by cartman0208

Sorry, the last Apache update made the webserver case sensitive (again ) ... Since the link points to Avisynth_260.exe but the file is named AviSynth_260.exe you got a 404

I just renamed the file, link should be working now.

Wow. When was that posted... I must have missed it completely.

[Edit] Ok, I see. It was part of the "3 frigg'n MONTHS behind" post. I guess I just missed that part.

[jdobbs]

Does anyone out there have some suggestions for a command line (for NVEncC.exe) that will create an .hevc file that is compatible with UHD blu-ray? I can create one that will compile and play (in UHD and HDR), but any attempts to fast forward/rewind or chapter skip will result in a blank screen (sound only). I've been beating my head against the wall for a couple days now -- and any help would be appreciated.

Thanks.

[Mike-uk]

Originally Posted by jdobbs

Does anyone out there have some suggestions for a command line (for NVEncC.exe) that will create an .hevc file that is compatible with UHD blu-ray? I can create one that will compile and play (in UHD and HDR), but any attempts to fast forward/rewind or chapter skip will result in a blank screen (sound only). I've been beating my head against the wall for a couple days now -- and any help would be appreciated.

Thanks.

mayby post the question on his blog ??

https://rigaya34589.blog.fc2.com/

[jdobbs]

Originally Posted by Mike-uk

mayby post the question on his blog ??

https://rigaya34589.blog.fc2.com/

Can you post in English in a thread that is in Japanese and has to be interpreted by Google translate?

I was under the impression that people have actually done UHD-BD encodes with this encoder. I'm hoping they can provide me with something that points out what I'm missing.

With this specific behavior I thought that maybe it wasn't creating I frames at the right distances/places, but I brought the resulting HEVC stream up with an HEVC browser and it looks like they are at the right places. I'm thinking now that maybe it's missing some of the supplementary information, but I'm not really sure? I guess I can do some comparisons to X265 output and see. But even if that is it -- I'd still need some way to add it.

[Sharc]

Originally Posted by jdobbs

Can you post in English in a thread that is in Japanese and has to be interpreted by Google translate?

You may want to report it as an issue here (in English):
https://github.com/rigaya/NVEnc/issues

[gonca]

Originally Posted by jdobbs

Does anyone out there have some suggestions for a command line (for NVEncC.exe) that will create an .hevc file that is compatible with UHD blu-ray? I can create one that will compile and play (in UHD and HDR), but any attempts to fast forward/rewind or chapter skip will result in a blank screen (sound only). I've been beating my head against the wall for a couple days now -- and any help would be appreciated.

Thanks.

I tried a barebones command line and I get the same symptoms. Plays fine start to finish, HDR and UHD recognized but ff, rw or chapter select I get black screen

[cartman0208]

Originally Posted by jdobbs

Does anyone out there have some suggestions for a command line (for NVEncC.exe) that will create an .hevc file that is compatible with UHD blu-ray? I can create one that will compile and play (in UHD and HDR), but any attempts to fast forward/rewind or chapter skip will result in a blank screen (sound only). I've been beating my head against the wall for a couple days now -- and any help would be appreciated.

Thanks.

Maybe it's something with the CU-Size ... I noticed that some months ago when I did some 4K testing with nvenc ...
Mediainfo doesn't show it (to me) ... can only be seen in VLC Player:
Video Resolution: 3840x2160
Buffer dimensions: 3840x2176

With CU Size set to 32 and 2160 isn't divisible by 32, result is set to 2176 which could end up in UHD incompatibility ...

In the original mt2s the values are identical.

So .. 2 possibilities ... setting CU size to 16x16 (if possible) or crop away 16 pix vertically and hope its still compatible

Just an idea ...

[jdobbs]

Originally Posted by gonca

I tried a barebones command line and I get the same symptoms. Plays fine start to finish, HDR and UHD recognized but ff, rw or chapter select I get black screen

Thanks for confirming it. My guess is there is some supplementary header information missing in the i-frame since that is what is used for FF/REW & CHAP jumps. I'm looking to see if I can find anything and possibly fix it myself. I can't find anything in the command line options that might change it significantly. Of course BD-RB fixing it would mean that after an encode I'd have to scan and rewrite the .hevc file (which can add some time to the process). I posted and error report on the site Sharc listed, hopefully someone will actually see it and respond -- but it looks like there are quite a bit of other reports there as well.

[jdobbs]

Originally Posted by cartman0208

Maybe it's something with the CU-Size ... I noticed that some months ago when I did some 4K testing with nvenc ...
Mediainfo doesn't show it (to me) ... can only be seen in VLC Player:
Video Resolution: 3840x2160
Buffer dimensions: 3840x2176

With CU Size set to 32 and 2160 isn't divisible by 32, result is set to 2176 which could end up in UHD incompatibility ...

In the original mt2s the values are identical.

So .. 2 possibilities ... setting CU size to 16x16 (if possible) or crop away 16 pix vertically and hope its still compatible

Just an idea ...

Interesting. If I look at the Sequence Parameter Set (NAL_SPS) it also tells me 3840x2176 for the picture height/width in luma samples, while in X265 it correctly says 3840x2160. But it plays when I insert the disc -- which makes me wonder what the significance of it is. You'd think an incorrect resolution would cause it to fail.

There's a discussion on this topic at this link. I'm not sure if there is a solution in the works...

[Edit]@cartman0208

The encoder allows me to set the CU to 16 (--cu-max 16) - but it seems to have no affect on the SPS value (as it still says 3840x2176 with a bottom offset of 8). The Blu-Ray spec specifically states that these values aren't allowed -- but my guess is that the player's hardware allows it (per the H.265 standard), and that's why the video is playing back. For right now I'm going to pretend this isn't the issue -- but I'll investigate further.

[MrVideo]

Originally Posted by jdobbs

There's a discussion on this topic at this link. I'm not sure if there is a solution in the works...

From what I read in the discussion is that nVidia is telling all the decoder manufactures that do not display 2176 as 2160 (by cropping bottom 16) to get with the spec and go screw yourself.

[cartman0208]

Originally Posted by jdobbs

[Edit]@cartman0208

The encoder allows me to set the CU to 16 (--cu-max 16) - but it seems to have no affect on the SPS value (as it still says 3840x2176 with a bottom offset of 8). The Blu-Ray spec specifically states that these values aren't allowed -- but my guess is that the player's hardware allows it (per the H.265 standard), and that's why the video is playing back. For right now I'm going to pretend this isn't the issue -- but I'll investigate further.

Yep, tried that too with the same result.
What I didn't try was my second suggestion ... initially crop away 16 pixel to a height of 2144, which is divisibly by 32...
Too small should be less of a problem then too big... or does the BluRay standard say EXACTLY 2160px in height?

I'm still wild guessing here, but maybe the screen can't display the oversize and stays blank ...

[gonca]

I cropped 280 top and bottom, script for a mkv file, and it behaved exactly the same
I know that is an illegal res for BD but the player didn't mind it.

[Sharc]

Originally Posted by jdobbs

Interesting. If I look at the Sequence Parameter Set (NAL_SPS) it also tells me 3840x2176 for the picture height/width in luma samples, while in X265 it correctly says 3840x2160. But it plays when I insert the disc -- which makes me wonder what the significance of it is. You'd think an incorrect resolution would cause it to fail.

There's a discussion on this topic at this link. I'm not sure if there is a solution in the works...

[Edit]@cartman0208

The encoder allows me to set the CU to 16 (--cu-max 16) - but it seems to have no affect on the SPS value (as it still says 3840x2176 with a bottom offset of 8). The Blu-Ray spec specifically states that these values aren't allowed -- but my guess is that the player's hardware allows it (per the H.265 standard), and that's why the video is playing back. For right now I'm going to pretend this isn't the issue -- but I'll investigate further.

Isn't this much the same as with x264 AVC: The coded size has always been 1920x1088 while the display size is 1920x1080?

[MrVideo]

Originally Posted by Sharc

Isn't this much the same as with x264 AVC: The coded size has always been 1920x1088 while the display size is 1920x1080?

Yep, that be the case.

[jdobbs]

Looking at the output from NVENCC, I'm guessing (but only guessing) that this may be the issue:

According to "White Paper Blu-ray Disc Read-Only Format Coding constraints on HEVC video streams for BD-ROM Version 3.0", page 6, each GOP (Group of Pictures) of the HEVC stream must start with an IDR (of course) -- and will contain one SPS (Sequence Parameter Set), one VPS (Video Parameter Set), and at least one PPS (Picture Parameter Set), and no more than 30 PPSs.

In dumping out the HEVC stream I'm finding that only the first GOP (the first IDR frame and following P/B frames in the file) meets this requirement. All the others IDR frames (start of GOP) I've looked at only have an AUD (Access Unit Delimeter) and a couple SEI's (Supplemental Enhancement Information) preceding the IDR slice.

I'll have to do some finagling with the stream to find out if this is truly the issue -- but it could make sense and explain why the stream can start playing from the beginning (the IDR that has the required information) but can't step into any of the others (FF/REW and CHAPTER SKIPS).

You never know, this may not be the problem at all... but I guess I'm going to have to find out somehow. In X265 you create a stream that contains the SPS/VPS/PPS in every GOP by using the --repeat-headers command line option. I'm hoping the same thing can be done in NVENCC.

I've added this information to my Issue Report at GITHUB. Hopefully someone with a little more HEVC/UHD-BD knowledge than me can confirm or deny this as the cause of the issue I'm seeing.

[Edit] In the meantime, I'm going to see how hard it would be for me to to scan and insert the headers via a software routine -- or if it is even possible. Unfortunately that would require me to read through the entire HEVC file and write a new one -- which requires significant processing time. In the end I may find out it isn't even the problem!

[jdobbs]

Originally Posted by jdobbs

Looking at the output from NVENCC, I'm guessing (but only guessing) that this may be the issue:

According to "White Paper Blu-ray Disc Read-Only Format Coding constraints on HEVC video streams for BD-ROM Version 3.0", page 6, each GOP (Group of Pictures) of the HEVC stream must start with an IDR (of course) -- and will contain one SPS (Sequence Parameter Set), one VPS (Video Parameter Set), and at least one PPS (Picture Parameter Set), and no more than 30 PPSs.

In dumping out the HEVC stream I'm finding that only the first GOP (the first IDR frame and following P/B frames in the file) meets this requirement. All the others IDR frames (start of GOP) I've looked at only have an AUD (Access Unit Delimeter) and a couple SEI's (Supplemental Enhancement Information) preceding the IDR slice.

I'll have to do some finagling with the stream to find out if this is truly the issue -- but it could make sense and explain why the stream can start playing from the beginning (the IDR that has the required information) but can't step into any of the others (FF/REW and CHAPTER SKIPS).

You never know, this may not be the problem at all... but I guess I'm going to have to find out somehow. In X265 you create a stream that contains the SPS/VPS/PPS in every GOP by using the --repeat-headers command line option. I'm hoping the same thing can be done in NVENCC.

I've added this information to my Issue Report at GITHUB. Hopefully someone with a little more HEVC/UHD-BD knowledge than me can confirm or deny this as the cause of the issue I'm seeing.

[Edit] In the meantime, I'm going to see how hard it would be for me to to scan and insert the headers via a software routine -- or if it is even possible. Unfortunately that would require me to read through the entire HEVC file and write a new one -- which requires significant processing time. In the end I may find out it isn't even the problem!

Well... even a broken clock is right twice a day.

That was it. I wrote some code to insert the SPS/VPS/PPS headers into the IDR of each GOP and... it fixed the issue. Fast Forward, Rewind and Chapter jumps now work.

I'll add code into BD-RB to correct the HEVC stream after encoding. It looks like it will add about 15 minutes or so to a job. But that's not bad considering how much time is saved using the NVENCC encoder. I just ran a complete job on a 2 hour and 22 minute UHD/HDR movie and it finished the encoding portion in less than 30 minutes (using the fastest setting).

I have to add supporting code for several subroutines before BD-RB is ready for a testing release -- expect it in the next week or so.

I will also update my issue information on GITHUB and hopefully all the will have to do is add a "--repeat-headers" command line function and make my workaround unneeded.

[Sharc]

Originally Posted by jdobbs

I will also update my issue information on GITHUB and hopefully all the will have to do is add a "--repeat-headers" command line function and make my workaround unneeded.

Now let's hope that rigaya takes action

[Ch3vr0n]

2h22m compared to what for you @jdobbs? 16hrs? ^^

[Mike-uk]

i guess this blank issue is only present on a bluray player, was playing the file on a pc ok ??

[jdobbs]

Originally Posted by Mike-uk

i guess this blank issue is only present on a bluray player, was playing the file on a pc ok ??

Yes. It was only an issue when authored into BD format and played on a Blu-Ray player. On a PC it had worked fine. I didn't test it, but I would assume an MKV or MP4 would probably have played even on the BD unit. The issue (needing the headers in each GOP) is related to the container type used in an authored BD.