Qt Multimedia status on Android

[George Tavares]

Hello BogDan

I am making some work with android multimedia  too, but in Camera
support and I make some progress that I can share with you.


I started with QtCamera.java/androidcamjni.cpp available in your sdk,
and tried direct render the image previews received in androidcamjni.cpp
to a QDeclarativeItem. The performance was not good.

I look in QtCamera.java and saw that frames are encoded to jpeg , and
later loaded to QImage,  I decided elimate this step, sending the
bytearrey of preview direct to CPP side and use a Method from Ketai
project! (decodeYUV420SP) to decode frame. After running, it continue
slow.

However, I am running qt with opengl enabled, then I decided upload YUV
frame like a texture and make de YUV decode in a shader. It now it is
fast. I can't see differences in my camera   support  (800x600) and the
camera from Android application. 

I have only one problem implementing the shader. the YUV format appears
like that:
YYYYYYYYY
UVUV

When I tried to load this like textures, I choose first load in two
textures, one with Y component of type GL_LUMINANCE  and other with UV
component with a type GL_LUMINANCE_ALPHA . In fragment shader I tried
load these components but the GL_LUMINANCE_ALPHA has some kind of bug
that the components are not load correctly. Then I decided to unscramble
the image in this format:
YYYYYYYYY
UUVV

Then I load the U and V texture separately. 


On Thu, 2012-05-03 at 19:07 +0300, BogDan Vatra wrote:

> RGB,
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