Formulae for U and V buffer offset

Question

Hi all !

What should be the buffer offset value for U & V in YUV444 format type?

Like for an example if i am using YV12 format the value is as follows:

ppData.inputIDMAChannel.UBufOffset = iInputHeight * iInputWidth + (iInputHeight * iInputWidth)/4; ppData.inputIDMAChannel.VBufOffset = iInputHeight * iInputWidth;

iInputHeight = 160 & iInputWidth = 112

ppdata is an object for the following structure:

    typedef struct ppConfigDataStruct
{
    //---------------------------------------------------------------
    // General controls
    //---------------------------------------------------------------
    UINT8         IntType;    
                  //    FIRSTMODULE_INTERRUPT: the interrupt will be 
                  //    rised once the first sub-module finished its job.
                  //    FRAME_INTERRUPT:   the interrput will be rised 
                  //    after all sub-modules finished their jobs.
    //---------------------------------------------------------------
    // Format controls
    //---------------------------------------------------------------

    // For input
    idmaChannel     inputIDMAChannel;

    BOOL            bCombineEnable;
    idmaChannel     inputcombIDMAChannel;
    UINT8           inputcombAlpha;
    UINT32          inputcombColorkey;

    icAlphaType     alphaType;

    // For output
    idmaChannel     outputIDMAChannel;
    CSCEQUATION  CSCEquation;    // Selects R2Y or Y2R CSC Equation
    icCSCCoeffs     CSCCoeffs;      // Selects R2Y or Y2R CSC Equation
    icFlipRot          FlipRot;        // Flip/Rotate controls for VF
    BOOL    allowNopPP;   // flag to indicate we need a NOP PP processing

}*pPpConfigData, ppConfigData;

and idmaChannel structure is as follows:

 typedef struct idmaChannelStruct
{
    icFormat       FrameFormat;  // YUV or RGB
    icFrameSize    FrameSize;  //  frame size
    UINT32         LineStride;//  stride in bytes
    icPixelFormat  PixelFormat;// Input frame RGB format, set NULL 
                                    // to use standard settings.
    icDataWidth    DataWidth;// Bits per pixel for RGB format
    UINT32    UBufOffset;// offset of U buffer from Y buffer start address
                            // ignored if non-planar image format
    UINT32    VBufOffset;// offset of U buffer from Y buffer start address
                            // ignored if non-planar image format    
} idmaChannel, *pIdmaChannel;

I want the formulae for ppData.inputIDMAChannel.UBufOffset & ppData.inputIDMAChannel.VBufOffset for YUV444

Thanks in advance

Answer 1

Given that YUV444 uses 8 bits per component, seems to me that the formulas should be straightforward:

ppData.inputIDMAChannel.UBufOffset = 2 * iInputHeight * iInputWidth;
ppData.inputIDMAChannel.VBufOffset = iInputHeight * iInputWidth;

Answer 2

Since YUV444 consist of 24 bit per pixel

Therefore the U & V buffer offset will be

ppData.inputIDMAChannel.UBufOffset = iInputHeight * iInputWidth;
ppData.inputIDMAChannel.VBufOffset = 2 * iInputHeight * iInputWidth;