H.265 / HEVC hardware decoding


DoodleMonger

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I was wondering if the Pyra will have hardware decoding support. I'm pretty new to this topic, and I understand that it's only recently being added into processors and Pyra's will be a bit out of date. So I'm guessing no.

Is this one of the things which might be made available with some future CPU/board update?

Could software decoding work, or is the CPU not powerful enough for that? What would be other bottlenecks for playing? 720p, disk access (USB3 SSD?), or can there be limitations using an external monitor?

Are there additional software considerations? I would assume VLC could handle it.
 

Binky

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Initially, I'd only bet on CPU decoding. I know the SoC has a handful of coprocessing units, so wouldn't be at all surprised if one of them can do video decompression. The problem is that software interfaces for them are awkward and poorly standardised - so it may take a while for someone to work out how to use the things!

Edit: I know that doesn't answer your codec-specific question. I'm sure someone else here knows far more about it than I!

This thread may be of interest:
https://pyra-handheld.com/boards/threads/demo-of-omap5-playing-video.74936/
 

Pocak

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The OMAP5 (Pyra's system on chip) was already sampling in 2013 when H.265 was ratified, so it couldn't possibly have hardware support for that. There is hardware for 8-bit H.264/AVC decoding (and encoding) as well as for some older formats, but don't expect it to work on launch day. And even after it's worked out, because TI exposes their codecs via OpenMAX, hw decoding will only be available in players that can use OMX: anything gstreamer based (e.g. Totem) and maybe VLC, but not mpv.

As for software decoding, my experience with a laptop of similar specs to the Pyra suggests that 720p H.265 is going to be ok, but 1080p is out of the question.

What would be other bottlenecks for playing? 720p, disk access (USB3 SSD?), or can there be limitations using an external monitor?
Typical bitrate for video is well below typical storage device speeds, so that's rarely a problem. I don't expect any limitation over HDMI compared to the Pyra's screen.
It's kind of funny, though, that the OMAP5's hw H.264 decoder is specced for 1080p at 120fps, but HDMI 1.4a is only able to pass 1080p at 60fps (or 30fps stereoscopic).
 

WizardStan

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The OMAP5 (Pyra's system on chip) was already sampling in 2013 when H.265 was ratified, so it couldn't possibly have hardware support for that.
It has a very capable DSP, same as the Pandora did, which should be more than powerful enough to handle 1080p h.265 encoded video.
Just like the Pandora, however, someone would need to write the codec for it.
Just like the Pandora, as well, I suspect that isn't likely to happen in the near future.
 

Pocak

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I would consider that software decoding as well, but more importantly, I think you're seriously overestimating the DSP's performance. David Schleef's theora decoder didn't turn out faster than the ARM version. And the amount of effort needed by @M-HT to get his scaler up to speed doesn't inspire much confidence either.

The Pyra's DSP's performance is going to be in the same ballpark as the Pandora's, with a higher clock speed but fewer execution units.
 

slaeshjag

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It has a very capable DSP, same as the Pandora did, which should be more than powerful enough to handle 1080p h.265 encoded video.
Just like the Pandora, however, someone would need to write the codec for it.
Just like the Pandora, as well, I suspect that isn't likely to happen in the near future.

No, the DSP in the pyra is nothing spectacular. There are several other hardware blocks in the OMAP5 for video processing, like IVA-HD and the VPE, and then there's ABE for audio processing. None of these are currently working.
 

DoodleMonger

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So far it sounds like transcoding down is going to be the way to go. 720p is (obviously) the target for the screen, but exploring things which are larger filesize but easier on the processor might be the way to go since I'd be transcoding anyway.

I may as well also be open to alternate video players, if it turns out one has better support for whatever technology than some other.

And no, I wouldn't expect (or encourage) any development effort whatsoever, seeing as the CPU is dated. The CPU board concept was particularly forward-looking. In five years, I'd likely pay another 1/3 the price for a CPU upgrade. My eyes clearly can't use 8k at that size/distance, and .. "4GB memory should be good enough for everyone."™

Now about that aluminium case..
 

TrashyMG

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Most 1080p h264 videos runs fine if you crank up the amount of threads dedicated for decoding h264 in smplayer, however not every player has the option to tweak that setting.
 
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