What does StageFright hardware acceleration actually do?

[Guest]

This is starting to puzzle me a little bit. What does the StageFright hardware acceleration (debug.sf.hw=1) do?

- OpenGL rendering is obviously already hardware accelerated, else GL would be dog-slow and the Blade would be unable to reasonably run any 3D game. Yet some people claim enabling SF hardware acceleration speeds up OpenGL games.

- 2D UI compositing is accelerated with the framebuffer driver.

- According to Google, only Honeycomb (3.0) recently introduced hardware acceleration for UI and 2D rendering.

So what does this option actually do? Please, can anyone explain?

[Guest k0zmic]

This is starting to puzzle me a little bit. What does the StageFright hardware acceleration (debug.sf.hw=1) do?

- OpenGL rendering is obviously already hardware accelerated, else GL would be dog-slow and the Blade would be unable to reasonably run any 3D game. Yet some people claim enabling SF hardware acceleration speeds up OpenGL games.

- 2D UI compositing is accelerated with the framebuffer driver.

- According to Google, only Honeycomb (3.0) recently introduced hardware acceleration for UI and 2D rendering.

So what does this option actually do? Please, can anyone explain?

Stagefright isn't hardware acceleration.

Hardware acceleration just speeds up the UI by utilising the GPU as well as the CPU I believe.

Stagefright is a Media Framework. It's used for making some games render properly on the Blade e.g. Gameloft ones. It's disabled by default as it gives extraordinarily high benchmark scores.

More on Stagefright here: http://android.modaco.com/content/zte-blad...41/stagefright/

Edited May 22, 2011 by k0zmic

[Guest]

Stagefright isn't hardware acceleration.

Why is the system property called debug.sf.hw then? I thought everything under debug.sf is Stagefright-specific. I can't really find much information about the extent of the Stagefright API (I know it covers video decoding and streaming, but that's probably not everything).

Anyway, it's beside the point. I'm specifically interested in what this so-called hardware acceleration actually accelerates and how. "Speeds up the UI by using the GPU"... well, that's not exactly saying much at all.

Edited May 22, 2011 by Guest

[Guest k0zmic]

Why is the system property called debug.sf.hw then? I thought everything under debug.sf is Stagefright-specific. I can't really find much information about the extent of the Stagefright API (I know it covers video decoding and streaming, but that's probably not everything).

Anyway, it's beside the point. I'm specifically interested in what this so-called hardware acceleration actually accelerates and how. "Speeds up the UI by using the GPU"... well, that's not exactly saying much at all.

Stagefright is this stuff:

media.stagefright.enable-player=true

media.stagefright.enable-meta=false

media.stagefright.enable-scan=true

media.stagefright.enable-http=false

Debug.sf.hw only controls whether Hardware acceleration is enabled or not. (hw=0) Uses the CPU to render the UI and (hw=1) Uses the GPU to render the UI.

I don't know how in detail how it works unfortunately.

[Guest Roph]

There really isn't any obvious benefit either way having stagefright on or off. One thing I would point out though is that if you want to play back HE-AAC/HE-AACv2 audio, you need to disable stagefright as it doesn't decode the files properly. My stagefright settings are:

media.stagefright.enable-player=false (or 0)

media.stagefright.enable-meta=true

media.stagefright.enable-scan=true

media.stagefright.enable-http=false

The meta/scan are I assume reading tags from files and the initial scan of your phone for music, videos and so on.

Edited May 23, 2011 by Roph

[Guest targetbsp]

debug.sf.hw accelerates some games but not many. Of the 28 games I have, only Leave Devil Alone benefits from it. But it REALLY needs it - it's unplayable without it. In a past thread about this, someone named another game that needs it to. Might have been Spiderman. I am aware of no other differences between it being on or off.

[Guest Mushroom_Lord]

Noob moment: How do you enable hardware acceleration And I know im not talking about stagefright :P

Is it only for certain ROMS (SS springs to mind :rolleyes:) - or is there something that can be edited (with relative ease), or is it a kernel job?

Edited May 24, 2011 by Mushroom_Lord

[Guest targetbsp]

Noob moment: How do you enable hardware acceleration And I know im not talking about stagefright :P

Is it only for certain ROMS (SS springs to mind :rolleyes:) - or is there something that can be edited (with relative ease), or is it a kernel job?

It's on by default in most Froyos and Cm7. In Froyo, the line above is in build.prop. Blade Buddy will toggle it to I believe.

[Guest Mushroom_Lord]

It's on by default in most Froyos and Cm7. In Froyo, the line above is in build.prop. Blade Buddy will toggle it to I believe.

Cheers :P

[Guest q123456]

is this affect battery life significantly? I mean when hw accel is on.

Edited June 5, 2011 by q123456

[Guest Roph]

It should decrease it. You always want to run things in hardware rather than software. The blades GPU drawing the user interface will result in less battery drain than the CPU having to do it.

[Guest q123456]

alright, thanks for clarifying