From ab13c66602322b5a6e840126986c1e7014edc125 Mon Sep 17 00:00:00 2001 From: "Steinar H. Gunderson" Date: Sun, 1 Nov 2015 13:45:45 +0100 Subject: [PATCH] Add some notes on GPU performance. --- README | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/README b/README index 0e61ef0..723ec4b 100644 --- a/README +++ b/README @@ -4,7 +4,7 @@ Nageru is a live video mixer, based around the standard M/E workflow. Features (those marked with * are still in progress or not started yet): - High performance on modest hardware (720p60 with two input streams - on my Thinkpad X240); almost all pixel processing is done on the GPU. + on my Thinkpad X240[1]); almost all pixel processing is done on the GPU. - High output quality; Lanczos3 scaling, subpixel precision everywhere, white balance adjustment (*), mix of 16- and 32-bit floating point @@ -19,6 +19,11 @@ Features (those marked with * are still in progress or not started yet): pipelines causing transitions etc., so that the visual look is consistent between operators. +[1] For reference, that is: Core i7 4600U (dualcore 2.10GHz, clocks down +to 800 MHz after 30 seconds due to thermal constraints), Intel HD Graphics +4400 (ie., without the extra L4 cache from Iris Pro), single-channel DDR3 RAM +(so 12.8 GB/sec theoretical memory bandwidth, shared between CPU and GPU). + Nageru is in alpha stage. It currently needs: @@ -53,7 +58,9 @@ To start it, just hook up your requipment, type “make” and then “./nageru It is strongly recommended to have the rights to run at real-time priority; it will make the USB3 threads do so, which will make them a lot more stable. (A reasonable hack for testing is probably just to run it as root using sudo, -although you might not want to do that in production.) +although you might not want to do that in production.) Note also that if you +are running a desktop compositor, it will steal significant amounts of GPU +performance. Nageru will open a HTTP server at port 9095, where you can extract a live H264+MP3 signal in MPEG-TS mux (e.g. http://127.0.0.1:9095/stream.ts). -- 2.39.2