delphi中调用vc dll的问题？

代码如下：

tgettime = function ( var sSourceFile:array of char;
var sDestinationFile:array of char;
IsOverCast:boolean;
usInputFlowRate:byte;
usOutputPCMLAW:byte;
var sErrorCodeBuffer:array of char;
bReserved:byte):boolean;

var
errorbuf,SourceFile,DestinationFile:array[0..511] of char;
other:byte;
libhandle :integer;
begin
SourceFile := 'D:\1.voc';
DestinationFile := 'd:\12.wav';
LibHandle:=LoadLibrary('adpcmdll.DLL');
if LibHandle=0 then
begin
Application.MessageBox('无此文件','警告',mb_ok+64);
exit;
end;
try
@Pcm2Wav:=GetProcAddress(LibHandle,'HU_AdpcmToWav');
if not(@Pcm2Wav=nil) then
Pcm2Wav(sourcefile,destinationfile,true,24,1,errorbuf,other);
finally
FreeLibrary(LibHandle);
end;

end;


调试时到Pcm2Wav(sourcefile,destinationfile,true,24,1,errorbuf,other)报写错误，不知道是什么原因，请教各位老大。