Choppy playback issue

[dream7]

Hello,

I'm in the process of authoring a Blu-ray for replication, and after burning a disc to my client for final validation he had problems with playback at some points of the movie, like big choppy playback. No issues with navigation and functionality. His player is an LG from 2010.
A technician at my replication plant said that it can be a problem of buffer with the encoding, too much peak with variable bitrate. I use x264 with recommended params.
I just asked for 1 month tryout of Scenarist BD, and when I export my BDS project to Scenarist and the muxing starts I have a warning :
Spec Error : BD-J Title(s) exists. If BD-J Application access PSR20, a player might not play back the disc normally.
Is this normal ?
Also, I see that scenarist apply a DTS-HD smoothing, it seems to smooth the peaks with the bitrate.
Does BDS internal muxer do this too ?

I tested my disc on about 10 players from different brands and got any issues with playback. but they are all relatively new. As my client said, he don't want to take the risk if the disc is not playable on even 5% of the players. Is there anything that can be done to check that the final mux or the encoded video is within specs ?

That's my first Blu-ray project and I don't want to mess around...

Thank you for your help !

[Alexey Kolesnikov]

Hello,

Did you or a plant checked the output with Sony/Panasonic verifiers? Can you send us video + audios that we can use to reproduce an issue? Can you film this choppy playback on a phone (for example) and send it to us? This will help us understand the places where issue happens.
If this is an issue with a bitrate you can try to limit the maximum bitrate. Additionally, old players may have issues with a laser.

Regarding the PSR20 - it is a region code. If you enabled "Project properties" -> "General" -> "Region limitation" -> "Check in Java too" - you can disable it. There is logPSR function as well that logs all PSRs, but if you do not call it intentionally it will not be called.

Regarding the smoothing - we do not modify streams during the mux process.

[mj0012]

Hello,

I'm in the process of authoring a Blu-ray for replication, and after burning a disc to my client for final validation he had problems with playback at some points of the movie, like big choppy playback. No issues with navigation and functionality. His player is an LG from 2010.

Before you get too far into troubleshooting I would suggest burning another copy for your client, maybe at a slower speed or using a different brand of disc. I've had these issues before and more often than not they are related to the player reading the burned BD-R disc and not how the disc was encoded or authored. The fact that your disc is also playing correctly on so many other players makes me think this might be a big possibility.

[MJS63]

" too much peak with variable bitrate. I use x264 with recommended params."

Out of curiosity what did you set your video data rate to? Is the DTS stream 5.1 or 2.0?
When the choppiness happens on the disc is there a lot going on picture and sound wise?

[dream7]

Hello,

thanks all for your suggestions. Sorry for the delay of my response, the project went slow because of multiple factors. I burned a BD-R with the slowest speed but it doesn't changed the issue.
The video datarate is 27Mbps + AC3 2.0 384kbps + DTS-HD MA 2.0.
I finaly get a Sony verifier check of the BDCMF from my plant. All the streams reported ok, so I think the choppy playback were because of a faulty player. But the verification is marked as "PASSED WITH WARNINGS" :

Allocation
WARNING: ALLOC1000
AV Stream File Allocation (1)
Because the value of "Start LSN on Layer 1" is not specified by user,
the verification related to Dual Layer is omitted.
#
File System
WARNING: UDF9998
UDF Verifier (1)
Because the value of "Start LSN on Layer 1" is not specified by user,
the verification related to Dual Layer is omitted.
#

I use BDS MX Pro 4.5.0.2019

How can I correct that ?

Thanks !

[Valery Koval]

Hi Dream7!

Can you please confirm that you are checking exact BDCMF structure (generated by BDS MX Pro) but not just generated ISO Image ?

Best,
Val.

[dream7]

Yes that's the BDCMF generated by BDS MX Pro.

[Alexey Kolesnikov]

Could you send us this CMF image?

[dream7]

Sent by mail.

Thank you for your help !

[Alexey Kolesnikov]

Hello,

We checked your BDCMF and did not find any issues.
Frankly, we never met "Because the value of "Start LSN on Layer 1" is not specified by user, the verification related to Dual Layer is omitted." before. Could you check with a factory - may be they did not specify something during the verification process?

PS: anyway, sent you an updated version - please try it and let us know if this helps.