Subject: Re: [bug#38403] [PATCH] gnu: Add intel-vaapi-driver-g45-h264.

From: Tobias Geerinckx-Rice <[email-masked]>
Date: Wed, 27 Nov 2019 19:58:19 +0100

Jelle,

Jelle Licht 写道：
> I am not sure if this package offers any practical benefit or 
> not, so I
> defer to someone who actually knows what they are talking about 
> to make
> a judgment call ;-).

I don't have a G45, but if this driver verifiably works for you 
(and the regular version does not) I think it's good to to include 
it.  Also because I expect this card to be overrepresented amongst 
Guix users: there aren't that many common Librebootable machines.

It needs its own clear synopsis, description, and home page 
though.  Is there a home page?  I'm not good at navigating 
BitBucket.

> This variant of intel-vaapi-driver is a backport of the ancient 
> g45-h264
> branch that used to be maintained by the intel-vaapi-driver 
> team. As far
> as I know, the reason they don't maintain this branch anymore is 
> that
> hardware accelerated h264 decoding on the G45 chipset was much 
> too slow
> for 1080p video, as by default it only had 32MB of VRAM to work 
> with.

These devices don't have their own RAM chips, so ‘by default’ here 
means the BIOS menu setting, right?  If so, it should be mentioned 
in the description for lack of upstream documentation.

I'm guessing that your card identifies as an Intel® GMA X4500MHD. 
Is that correct?  We should include the marketing name in the 
synopsis & description too, even if it might not map 1:1 to the 
chipset.

> This variant of intel-vaapi-driver is a backport of the ancient 
> g45-h264
> branch that used to be maintained by the intel-vaapi-driver 
> team. As far
> as I know, the reason they don't maintain this branch anymore is 
> that
> hardware accelerated h264 decoding on the G45 chipset was much 
> too slow
> for 1080p video, as by default it only had 32MB of VRAM to work 
> with.

This is good! :-)  It should be slightly edited and used as a 
description together with the original intel-vaapi-driver text.

Apart from that, the package LGTM.  Thanks!

Kind regards,

T G-R