On Wed, Dec 13, 2017 at 06:22:14PM +0200, Ville Syrjälä wrote:
On Wed, Dec 13, 2017 at 11:12:18AM -0500, Ilia Mirkin wrote:
On Wed, Dec 13, 2017 at 10:41 AM, Daniel Stone daniel@fooishbar.org wrote:
Hi Russell,
On 8 December 2017 at 12:31, Russell King rmk+kernel@armlinux.org.uk wrote:
Add the defacto-standard "iturbt_709" property to the overlay plane to control the YUV to RGB colorspace conversion. This is mutually exclusive with the CSC_YUV CRTC property - the last property to be set determines the resulting colorspace conversion.
I haven't seen this in other drivers - is it a 'defacto standard'? I
xf86-video-nv supported it, and I added it to nouveau as well when I ported YUV plane support. Some video players use the Xv property when available.
https://cgit.freedesktop.org/xorg/driver/xf86-video-nv/tree/src/nv_video.c#n... https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/driv...
{XvSettable | XvGettable, 0, 1, "XV_ITURBT_709"}
Who came up with that and when? XV_COLORSPACE was the one semi-standard I know of.
I've no idea, and I was hoping that someone else would know - my use of it comes from research into what will make userspace work, not what standards may say.
XV_ITURBT_709 is already in-use in distro standard userspace programs:
# grep XV_ITURBT_709 /usr/lib/vlc/plugins/ -r Binary file /usr/lib/vlc/plugins/video_output/libxcb_xv_plugin.so matches # grep XV_ITURBT_709 /usr/lib/gstreamer-1.0/ -r Binary file /usr/lib/gstreamer-1.0/libgstxvimagesink.so matches
but not XV_COLORSPACE:
# grep XV_COLORSPACE /usr/lib/vlc/plugins/ -r # grep XV_COLORSPACE /usr/lib/gstreamer-1.0/ -r
So while XV_COLORSPACE may be some kind of standard, it seems that userspace has decided otherwise to go with a different name for this control.
Anyway, I'll drop this patch and send a pull request for the remainder to David.