C55x WMA Callback function

Hello,

we are on the way to debug C55x WMA decoder program.

I have a question about WMA Callback function.

WMA_Version9_Decoder_C55X_UserGuide.pdf in C:\REL.50.A.WMA.D.STv9.C55X.01.00.00.001\50_A_WMA_D_1_00_00\C55X_WMA\Docs describes as follows,

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4.2  Callback Function

WMA Decoder uses callback function to read input data from the file. Test
Application shall define the callback function and pointer to this function is
passed as a parameter to decoder. Below is the prototype of the callback
function.

Typedef tWMA_U32 (*tpCallBackFun)(tHWMAFileState
hstate, tWMA_U32 offset,
    tWMA_U32 num_bytes, tStreamData **ppData);

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Could you please tell me about the meaning of above each parameters?

state:

offset:

num_bytes:

ppData:

I can not find any information above four parameters on WWW, WMA resource folders.

Best regards,

ay0689_2