Youtube on the N900

After my implementation of local rendering, Flash plays quite well on the N900. In fact, with a plain Qt flash loader (npploader - git://git.forwardbias.in/npploader.git), I get ~70fps. With a QWebView, the fps goes down to around ~50fps. With a QGraphicsWebView, the fps goes to around 55fps. Tested with fps tester.

This is not so bad but youtube was still rendering very badly compared to Fennec. With help from Nokia folks, I found out that the codec being served for Fennec is H.263 Sorenson and Qt/WebKit was being served H.264. The difference in quality would have been blindingly obvious had I paid more attention :-) On the n900, Sorenson Spark is the fast codec that is hardware accelerated (Documented here). If you use N900 to watch Youtube, append &fmt=5 to the Youtube url for better viewing.

Youtube serves sorenson based on the UA and I did some elaborate tests to figure what exactly it was looking for in the UA so we can add the same to Qt/WebKit for Maemo5. The long result is below. The short result is that it expects "Firefox/3.5" and "Maemo Browser" in the UA. Unfortunately, we cannot add "Firefox/3.5" as that would mean Qt/WebKit might get served Fennec optimized sites :(

One options, of course, is to contact Youtube and ask them to serve a different codec for Qt/WebKit's UA but we are not pursuing this because this is really not important :) I have a patch to Qt/WebKit that adds "Firefox/3.5 Maemo Browser" to our UA for *.youtube.com by extending the existing QWebPage::userAgentForUrl(). Simon and Harald are brooding over whether we should bother adding this change. Time will tell whether we will apply it.

Results of the test:

Current Qt/WebKit UA - Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3
Current Fennec UA - Mozilla/5.0 (X11; U; Linux armv7l; en-US; rv:1.9.2.1) Gecko/20100126 Firefox/3.5 Maemo Browser 1.7.4.8 RX=51 N900

H.264 desktop UI
-----------------
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox/3.5
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox/3.5 N900
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 N900
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox Maemo

Mobile UI (same ui as m.youtube.com - 3gp/rtsp)
-----------------------------------------------
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Maemo Browser
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Maemo Browser 1.7.4.8
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Maemo Browser 1.7.4.8 RX=51
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Maemo Browser 1.7.4.8 RX=51 N900
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 N900/Maemo Browser

Sorenson + desktop UI
---------------------------
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox/3.5 Maemo Browser
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox/3.5 Maemo Browser 1.7.4.8
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox/3.5 Maemo Browser 1.7.4.8 RX=51
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox/3.5 Maemo Browser 1.7.4.8 RX=51 N900
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox/3.5 N900/Maemo Browser
Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/533.3 (KHTML, like Gecko) Qt/4.7.0 Mobile Safari/533.3 Firefox Maemo Browser