Split up the forward DCT routine into three stages

Divide it into sample conversion, DCT and quantization in order to
easily provide alternative implementations of each stage.


git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@13 632fc199-4ca6-4c93-a231-07263d6284db

jdct.h

@@ -32,9 +32,6 @@ typedef int DCTELEM;		/* 16 or 32 bits is fine */
 typedef INT32 DCTELEM;		/* must have 32 bits */
 #endif
 
-typedef JMETHOD(void, forward_DCT_method_ptr, (DCTELEM * data));
-typedef JMETHOD(void, float_DCT_method_ptr, (FAST_FLOAT * data));
-
 
 /*
  * An inverse DCT routine is given a pointer to the input JBLOCK and a pointer