Qt Multimedia status on Android

[BogDan]

Hi Michał,

> 
>
>This code should work with android-11 and if we disable checking preferred preview size it's good for android-9 (where camera was introduced).
>

What do you mean by "android-9 (where camera was introduced)" ? Camera is in android since API Level 1, it was just changed over the time !
Anyway, make sure yours change will not break android-4 to android-8 !

>
>We don't share? (-: I published it as an answer at some topic about camera issue.

I'm sorry, I didn't see it until now :(, sadly I don't have time to read all topics on android-qt :( ! So, if you have something which might be used by many other people and you don't have an answer on the mailing lists, please send me a private mail !


> Is there any special place for this?
>

Yes, there are a few: use this mailing list to announce it and to discuss it and https://git.reviewboard.kde.org/dashboard/ to upload your patch (when is completed) !


>Cheers,
>Michał
>

Cheers,
BogDan.

>
>
>2012/5/6 BogDan <bog_dan_ro at yahoo.com>
>
>Hi,
>>
>>
>>Nice article !
>>
>>
>>At least for android-14+ I think it is possible to use another approach, I wrote another mail about about it, any comments will be highly appreciate ! :)
>>
>>
>>
>>Cheers,
>>BogDan.
>>
>>
>>P.S. Folks if you have solutions why don't you share them with us ?
>>
>>
>>
>>
>>
>>>________________________________
>>> From: Michał Kowalczyk <mkk at ekk.pl>
>>>To: BogDan <bog_dan_ro at yahoo.com> 
>>>Cc: George Tavares <tavares.george at gmail.com>; "necessitas-devel at kde.org" <necessitas-devel at kde.org> 
>>>Sent: Friday, May 4, 2012 8:23 PM
>>>
>>>Subject: Re: Qt Multimedia status on Android
>>> 
>>>
>>>
>>>Couple weeks ago I published solution which is similar to yours, George:
>>>http://mkk.ekk.pl/?wpis=4
>>>I use OpenGL only for acceleration of displaying frames (it takes lot of time, what is really strange). I provided decoding YUV into RGB, try to do some optimization and use all accessible CPU cores. Maybe it is possible to make it better. I hope it will be useful for you.
>>>
>>>Cheers,
>>>Michał
>>>
>>>
>>>
>>>2012/5/4 BogDan <bog_dan_ro at yahoo.com>
>>>
>>>Hello George,
>>>>
>>>>>________________________________
>>>>> From: George Tavares <tavares.george at gmail.com>
>>>>>To: necessitas-devel at kde.org
>>>>>Sent: Thursday, May 3, 2012 11:13 PM
>>>>>Subject: Re: Qt Multimedia status on Android
>>>>
>>>>>
>>>>>
>>>>>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.
>>>>>
>>>>
>>>>Maybe we should join forces ?:)
>>>>
>>>>
>>>>
>>>>>
>>>>>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.
>>>>>
>>>>
>>>>Great, can you please share with us the shader sources ?
>>>>
>>>>As I sad I already have the texture, the problem is how to display it on a non-gl widget ...
>>>>Using OpenGL for rendering everything it can be a solution but sadly on android we
>>>>
>>>>are limited to a single windowsurface, so the UI is (extremely) limited to a single
>>>>
>>>>Top Level Widget, this means you can't use controls which needs another TLW
>>>>(e.g. dialog, combobox, etc.).
>>>>
>>>>Check http://code.google.com/p/android-lighthouse/issues/detail?id=4#c24 for
>>>>
>>>>more informations.
>>>>
>>>>
>>>>
>>>>Thanks,
>>>>
>>>>
>>>>Cheers,
>>>>BogDan.
>>>>
>>>>P.S. Please join the mailing list to https://mail.kde.org/mailman/listinfo/necessitas-devel
>>>>
>>>>_______________________________________________
>>>>Necessitas-devel mailing list
>>>>Necessitas-devel at kde.org
>>>>https://mail.kde.org/mailman/listinfo/necessitas-devel
>>>>
>>>
>>>
>>>
>
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