My recent UHD rips of The Matrix series and Blade Runner play 'hot' on my Macbook Pro 2016 using VLC. The processor reaches around 90C and fans go full blast.
I suspect this is the result of software decoding, but I am unsure. My MBP processor has 1st generation HEVC decoding, but I'm not sure if this is applying to this MKV or it is running hot for another reason (maybe due to being 4k?).
Any reason why this might be happening?
UHD MKV playback not using hardware decoding
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premiumcapture
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Re: UHD MKV playback not using hardware decoding
What does Activity Monitor show when you're playing a movie in VLC? (https://support.apple.com/guide/activit ... elcome/mac)
VLC has controls to enable or disable hardware acceleration for decoding. What is yours set to? (https://wiki.videolan.org/VLC_HowTo/Har ... eleration/)
Probably doesn't hurt to make sure you've got the latest VLC too, 3.0.11.1.
Finally, playing a UHD rip on a laptop might be overkill. I'm sure the Blu-ray version would look fine, take up less disk space and be easier to play.
VLC has controls to enable or disable hardware acceleration for decoding. What is yours set to? (https://wiki.videolan.org/VLC_HowTo/Har ... eleration/)
Probably doesn't hurt to make sure you've got the latest VLC too, 3.0.11.1.
Finally, playing a UHD rip on a laptop might be overkill. I'm sure the Blu-ray version would look fine, take up less disk space and be easier to play.
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premiumcapture
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Re: UHD MKV playback not using hardware decoding
CPU usage appears to be about 30%+, I made sure that hardware acceleration was enabled, and has been throughout. VLC is up to date, but open to alternative playback solutions.
Agreed that UHD not necessary on laptop, but playing back file directly from home network, and prefer not to have a second copy taking up space.
Agreed that UHD not necessary on laptop, but playing back file directly from home network, and prefer not to have a second copy taking up space.
Re: UHD MKV playback not using hardware decoding
If CPU usage for playback of a 4K UHD is around 30% then it seems like you're getting hardware acceleration. That's about the same CPU usage I get using VLC on a UHD on my 2017 iMac. If I use mpv, which doesn't use hardware acceleration, my CPU usage is often 200%. I'm guessing Macs of our era use Intel Quick Sync hardware acceleration. As a side note, VLC uses 10% - 15% on my machine when playing a MKV blu-ray. VLC uses about 8% playing a h.264 encode of the aforementioned blu-ray. Quicktime uses 3% - 4% when playing the same h.264 file.
I think the 2018 MBP was the first with the T2 chip. https://support.apple.com/en-us/HT208862 I'm fairly certain in Macs with a T2 chip, that chip handles HEVC encode/decode.
Certainly, moving the relatively large UHD file over wifi will be a non-trivial thing, contributing to the heat produced by your laptop. Out of curiosity, what happens if you copy the file to local storage and play it from there? VLC won't be any more efficient, but wifi would be idle and that might help keep your laptop cooler.
And you could consider finding an iFixit guide to take the bottom case of your laptop to be able to blow out any accumulated dust.
I think the 2018 MBP was the first with the T2 chip. https://support.apple.com/en-us/HT208862 I'm fairly certain in Macs with a T2 chip, that chip handles HEVC encode/decode.
Certainly, moving the relatively large UHD file over wifi will be a non-trivial thing, contributing to the heat produced by your laptop. Out of curiosity, what happens if you copy the file to local storage and play it from there? VLC won't be any more efficient, but wifi would be idle and that might help keep your laptop cooler.
And you could consider finding an iFixit guide to take the bottom case of your laptop to be able to blow out any accumulated dust.
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premiumcapture
- Posts: 8
- Joined: Fri Sep 19, 2014 2:56 am
Re: UHD MKV playback not using hardware decoding
It seems I might have misread the screen thinking there was an issue with presentation. Seeing the 200% made me take another look, and it seems my CPU usage is actually 300%, which I didn't think was possible. From what you've just shared, it seems it is not using hardware decoding then.
I keep my laptop on a small table tray that fits it with no additional space, so hdd not an option at this point. Because I am not using the full benefit of 4K on such a small screen, I may just end up having a smaller copy be there anyways. Going to play with x265 to see if it hardware decodes there and whether the UHD format/colorscheme is maybe requiring the software decode.
I keep my laptop on a small table tray that fits it with no additional space, so hdd not an option at this point. Because I am not using the full benefit of 4K on such a small screen, I may just end up having a smaller copy be there anyways. Going to play with x265 to see if it hardware decodes there and whether the UHD format/colorscheme is maybe requiring the software decode.