diff -r 43e37759235e -r 51a74ef9ed63 Symbian3/SDK/Source/GUID-AFD7E241-7DC5-5C7B-A7FB-D0B6DCF95ECD.dita --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Symbian3/SDK/Source/GUID-AFD7E241-7DC5-5C7B-A7FB-D0B6DCF95ECD.dita Wed Mar 31 11:11:55 2010 +0100 @@ -0,0 +1,120 @@ + + + + + +Rendering +Video to a Graphics Surface TutorialThis tutorial shows you how to use the Video Renderer utility class +to create a new surface for rendering and render a video buffer onto the display. +

Before you start, +you must:

    +

  • Understand the Video Renderer.

    • +
 +

You use the CVideoRenderer utility +class to render video to a graphics surface. CVideoRenderer has +two modes:

    +

  • Timed

    In +timed mode, a frame is rendered at a specific time called its presentation +time. A frame's presentation time is the system clock time when that frame +must be visible on the display. CVideoRenderer launches its +own high-priority thread to handle timed rendering.

    • +

  • Non-timed

    In +non-timed mode, a frame is rendered as soon as possible. Non-timed mode requires +a CActiveScheduler to be present in the calling thread.

    • +

CVideoRenderer uses the MVideoRendererObserver interface +to provide notifications about the status of video buffers. MVideoRendererObserver provides +the following notifications:

+ + + + Callback +Description + + + + +

MVideoRendererObserver::MvroBufferDisplayed(TInt,const + TTime &)

+

A buffer has been rendered onto the display.

+ + +

MVideoRendererObserver::MvroBufferSkipped(TInt)

+

A buffer was skipped in the rendering process. This could be because +it missed its presentation time or an error occurred.

+ + +

MVideoRendererObserver::MvroVideoBufferAvailable()

+

A new buffer is available which can be used to store a video frame +for rendering.

+ + + +

Note: You must implement MVideoRendererObserver to +receive these notifications.

+ +Create a new Video +Renderer instance by calling CVideoRenderer::NewL(MVideoRendererObserver&, +TBool). +Set the aTimed parameter to ETrue for +timed mode or EFalse for non-timed mode. +//Create new timed Video Renderer +CVideoRenderer* renderer = CVideoRenderer::NewL(observer, ETrue); +If in timed mode, CVideoRenderer launches its +own high-priority thread. + +Get the list of +supported surface formats by calling CVideoRenderer::GetSupportedFormatsL(RArray<TUncompressedVideoFormat>&). +The Video Renderer maintains a list of supported formats in an RSS file. +For more information, see Video +Renderer Resource File. +//Get an array of supported formats +renderer->GetSupportedFormatsL(array); + GetSupportedFormatsL() returns an array of supported +formats. Use the supported format you require as an input parameter when creating +your surface. + +Create a new surface +for rendering by calling CVideoRenderer::CreateSurfaceL(const +TSize&, TInt, const TUncompressedVideoFormat&, TSurfaceId&) +TSurfaceId surfaceId; +renderer->CreateSurfaceL(size, buffers, format, surfaceId); + CVideoRenderer::CreateSurfaceL() returns a Surface +ID for the new surface. You use the Surface ID whenever you need to refer +to the surface, for example, when you need to destroy it. + +Retrieve the next +free buffer from the Video Renderer by calling CVideoRenderer::NextBuffer(). +TVideoFrameBuffer* buffer = renderer->NextBuffer(); +// use buffer +

Note you should only perform this step after your observer's MvroVideoBufferAvailable() routine +has been called.

 + CVideoRenderer::NextBuffer() returns the next +available buffer. + +Render the buffer +onto the display by calling CVideoRenderer::UpdateBuffer(TVideoFrameBuffer +*,const TTime &). +If you created your Video Renderer in timed mode, set aPresentationTime to +be the required presentation time for the buffer. If you created your Video +Renderer in non-timed mode, then aPresentationTime is ignored +and the buffer is displayed as soon as possible. +FillWithData(buffer->Buffer()); // Fills buffer with data +renderer->UpdateBuffer(buffer, presentationTime); +When the buffer has been displayed, you are notified via the MVideoRendererObserver::MvroBufferDisplayed(TInt,const TTime + &) callback. + + +

You have now created +a surface and rendered a video buffer onto the display.

+ +Video Player +2 Tutorial +Writing a +Controller Plug-in + \ No newline at end of file