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I'm posting this from mobile so sorry for any mistakes or bad formatting.

So finally got my PI 3B+ two days ago, installed the latest image available (from the download section, that i assume is a stable release) and it started perfectly... I made ZERO changes in the config for the exception of configuring the WiFi and adding my local NAS, and when i tried to play a movie puff the unit got a black screen and no longer responded to SSH requests or the attached keyboard.

So long story short I've tried a lot of things but in the end it was MMAL hardware acceleration being on by default that was causing the crashes... I've turned it off and OMX ON and now it works perfectly.... Even added add-ons now.
Except that isn't MMAL hardware acceleration supposed to work?

Any ideas? I've run stress tests, multiple PSUs with 3 Amps, tested for undervoltage, etc, etc and i cant find any indication of what is wrong.

I can upload logs latter if needed, just tell me witch ones.

Thank you.
(5th Jul, 2019 05:56 AM)Exnor Wrote: [ -> ]I'm posting this from mobile so sorry for any mistakes or bad formatting.

So finally got my PI 3B+ two days ago, installed the latest image available (from the download section, that i assume is a stable release) and it started perfectly... I made ZERO changes in the config for the exception of configuring the WiFi and adding my local NAS, and when i tried to play a movie puff the unit got a black screen and no longer responded to SSH requests or the attached keyboard.

So long story short I've tried a lot of things but in the end it was MMAL hardware acceleration being on by default that was causing the crashes... I've turned it off and OMX ON and now it works perfectly.... Even added add-ons now.
Except that isn't MMAL hardware acceleration supposed to work?

MMAL acceleration is working for many years w/o any issue

Quote:Any ideas? I've run stress tests, multiple PSUs with 3 Amps, tested for undervoltage, etc, etc and i cant find any indication of what is wrong.

I can upload logs latter if needed, just tell me witch ones.

I don't think that logs would help, because it seems that your Pi is freezing completely, or does your Pi still respond to a ping request?

Could you share a sample video so I could check of this crash happens here also?

Quote:Thank you.

You're welcome Smile
(6th Jul, 2019 03:04 AM)Nachteule Wrote: [ -> ]
(5th Jul, 2019 05:56 AM)Exnor Wrote: [ -> ]I'm posting this from mobile so sorry for any mistakes or bad formatting.

So finally got my PI 3B+ two days ago, installed the latest image available (from the download section, that i assume is a stable release) and it started perfectly... I made ZERO changes in the config for the exception of configuring the WiFi and adding my local NAS, and when i tried to play a movie puff the unit got a black screen and no longer responded to SSH requests or the attached keyboard.

So long story short I've tried a lot of things but in the end it was MMAL hardware acceleration being on by default that was causing the crashes... I've turned it off and OMX ON and now it works perfectly.... Even added add-ons now.
Except that isn't MMAL hardware acceleration supposed to work?

MMAL acceleration is working for many years w/o any issue

Quote:Any ideas? I've run stress tests, multiple PSUs with 3 Amps, tested for undervoltage, etc, etc and i cant find any indication of what is wrong.

I can upload logs latter if needed, just tell me witch ones.

I don't think that logs would help, because it seems that your Pi is freezing completely, or does your Pi still respond to a ping request?

Could you share a sample video so I could check of this crash happens here also?

Quote:Thank you.

You're welcome Smile

After a few hours tinkering i found out that the unit only freezes because by default the option to adjust the refresh rate to the one of the media (ex 24 fps or tv 30 fps) was on... Now my tv supports those inputs but once I've deselected the option no more crashes so far.

I have no idea why this happened.... The fact is now both mmal and omx hardware acceleration are working.
Tested with several codecs and bit rates so unless i came across another but I'm marking this as solved Smile


Thanks Nachteule Smile

Ps: the unit would crash completely... No network response, nothing.
Hmmm, that's weird ConfusedHuh

Maybe you have to setup whitelist of resolution/refresh rate in Settings->System->Display.

Disabling that option does not make sense, you won't get smooth playing of videos. I've that option always on!
(6th Jul, 2019 07:10 AM)Nachteule Wrote: [ -> ]Hmmm, that's weird ConfusedHuh

Maybe you have to setup whitelist of resolution/refresh rate in Settings->System->Display.

Disabling that option does not make sense, you won't get smooth playing of videos. I've that option always on!

Very weird... I would expect losing image but not a full crash ...

Anyway i only care for "true cinema" frame rate on my Blu-ray's (24fps) and for those i use an LG Blu-ray player.

For other sources I've always used 60fps output... So for now its not a problem.

Off topic: I've tested a 1080p HEVC movie rip and it works better than on my desktop :o. Its looks perfect. What kind of magic is going on here?
(7th Jul, 2019 12:27 AM)Exnor Wrote: [ -> ]
(6th Jul, 2019 07:10 AM)Nachteule Wrote: [ -> ]Hmmm, that's weird ConfusedHuh

Maybe you have to setup whitelist of resolution/refresh rate in Settings->System->Display.

Disabling that option does not make sense, you won't get smooth playing of videos. I've that option always on!

Very weird... I would expect losing image but not a full crash ...

Anyway i only care for "true cinema" frame rate on my Blu-ray's (24fps) and for those i use an LG Blu-ray player.

For other sources I've always used 60fps output... So for now its not a problem.

Off topic: I've tested a 1080p HEVC movie rip and it works better than on my desktop :o. Its looks perfect. What kind of magic is going on here?

Yep, 1080p HEVC support was usable starting with Kodi Krypton and was optimized for Leia. A lot of inline assembly and cooperation with MMAL acelleration made it possible to play 1080p HEVC smoothy Big Grin
(7th Jul, 2019 02:35 AM)Nachteule Wrote: [ -> ]
(7th Jul, 2019 12:27 AM)Exnor Wrote: [ -> ]
(6th Jul, 2019 07:10 AM)Nachteule Wrote: [ -> ]Hmmm, that's weird ConfusedHuh

Maybe you have to setup whitelist of resolution/refresh rate in Settings->System->Display.

Disabling that option does not make sense, you won't get smooth playing of videos. I've that option always on!

Very weird... I would expect losing image but not a full crash ...

Anyway i only care for "true cinema" frame rate on my Blu-ray's (24fps) and for those i use an LG Blu-ray player.

For other sources I've always used 60fps output... So for now its not a problem.

Off topic: I've tested a 1080p HEVC movie rip and it works better than on my desktop :o. Its looks perfect. What kind of magic is going on here?

Yep, 1080p HEVC support was usable starting with Kodi Krypton and was optimized for Leia. A lot of inline assembly and cooperation with MMAL acelleration made it possible to play 1080p HEVC smoothy Big Grin

You are a genius mate Smile

How did you manage to get better performance on quad core ARMv7 @ 1.4GHz (don't know how many IPC and MIPS on a Cortex A53 and i noticed you are not using the ARMv8 advantages this cores have or am i wrong? This is still a 32 bit build right?) that i have on a x86-64 quad core AMD clocked @ 3.2 GHz ( 4 SMTs also) ? Plus the VideoCore IV is a joke compared to my desktop GPU and still...

Kudos. I would love to know and understand how you manage this.

And a big thank you for all the work Big Grin
(7th Jul, 2019 08:39 AM)Exnor Wrote: [ -> ]You are a genius mate Smile

How did you manage to get better performance on quad core ARMv7 @ 1.4GHz (don't know how many IPC and MIPS on a Cortex A53 and i noticed you are not using the ARMv8 advantages this cores have or am i wrong? This is still a 32 bit build right?) that i have on a x86-64 quad core AMD clocked @ 3.2 GHz ( 4 SMTs also) ? Plus the VideoCore IV is a joke compared to my desktop GPU and still...

I'm not the developer who did this. I just picked necessary commits and merged them in our source tree. This patch is extremely efficient, so even a RPi2 can play a lot of 1080p HEVC videos smoothliy Smile

Quote:Kudos. I would love to know and understand how you manage this.

Here you can find the main patch. As you can see, the patch for ffmpeg is so big that github does not display it on the webui

Quote:And a big thank you for all the work Big Grin
(7th Jul, 2019 07:25 PM)Nachteule Wrote: [ -> ]I'm not the developer who did this. I just picked necessary commits and merged them in our source tree. This patch is extremely efficient, so even a RPi2 can play a lot of 1080p HEVC videos smoothliy Smile

Quote:Kudos. I would love to know and understand how you manage this.

Here you can find the main patch. As you can see, the patch for ffmpeg is so big that github does not display it on the webui

Quote:And a big thank you for all the work Big Grin

Is it possible to apply this method to an x86 machine?
(9th Jul, 2019 12:53 AM)Exnor Wrote: [ -> ]Is it possible to apply this method to an x86 machine?

It has already been done: The magic word is vaapi support for ffmpeg. Of course, your CPU/GPU/VPU/APU must have the decoder builtin Tongue
(9th Jul, 2019 03:42 AM)Nachteule Wrote: [ -> ]
(9th Jul, 2019 12:53 AM)Exnor Wrote: [ -> ]Is it possible to apply this method to an x86 machine?

It has already been done: The magic word is vaapi support for ffmpeg. Of course, your CPU/GPU/VPU/APU must have the decoder builtin Tongue

Thanks for the link, that was a lot of reading that left me with even more questions lol.

What you do on the Pi2 an 3 is partially using the ARM cores to decode HEVC right? This allows for that extraordinary decode performance that i saw, but this VAAPI for what i was able to understand uses the GPU or embedded GPU on x86 ... Or did i misunderstand?

Even so, do you have any info if did team Kodi used this on the Leia version for Windows 10? Because my compute stick is on the Intel list of supported CPU+ GPU and i can't get that kind of performance even when forcing DXVA2.

By googling for Kodi + VAAPI i get only Linux related articles....

Thanks Smile
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