jxrlib: Add library sources

jxrlib/image/sys/strTransform.c

@@ -0,0 +1,85 @@
+//*@@@+++@@@@******************************************************************
+//
+// Copyright <20> Microsoft Corp.
+// All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+// 
+// <20> Redistributions of source code must retain the above copyright notice,
+//   this list of conditions and the following disclaimer.
+// <20> Redistributions in binary form must reproduce the above copyright notice,
+//   this list of conditions and the following disclaimer in the documentation
+//   and/or other materials provided with the distribution.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+//*@@@---@@@@******************************************************************
+
+#include "strTransform.h"
+
+/** need to swap b and c **/
+/** rounding behavior: [0 0 0 0] <-> [+ - - -]
+    [+ + + +] <-> [+3/4 - - -]
+    [- - - -] <-> [- - - -] **/
+Void strDCT2x2dn(PixelI *pa, PixelI *pb, PixelI *pc, PixelI *pd)
+{
+    PixelI a, b, c, d, C, t;
+    a = *pa;
+    b = *pb;
+    C = *pc;
+    d = *pd;
+  
+    a += d;
+    b -= C;
+    t = ((a - b) >> 1);
+    c = t - d;
+    d = t - C;
+    a -= d;
+    b += c;
+
+    *pa = a;
+    *pb = b;
+    *pc = c;
+    *pd = d;
+}
+
+Void strDCT2x2up(PixelI *pa, PixelI *pb, PixelI *pc, PixelI *pd)
+{
+    PixelI a, b, c, d, C, t;
+    a = *pa;
+    b = *pb;
+    C = *pc;
+    d = *pd;
+  
+    a += d;
+    b -= C;
+    t = ((a - b + 1) >> 1);
+    c = t - d;
+    d = t - C;
+    a -= d;
+    b += c;
+
+    *pa = a;
+    *pb = b;
+    *pc = c;
+    *pd = d;
+}
+
+Void FOURBUTTERFLY_HARDCODED1(PixelI *p)
+{
+    strDCT2x2dn(&p[0], &p[4], &p[8], &p[12]);
+    strDCT2x2dn(&p[1], &p[5], &p[9], &p[13]);
+    strDCT2x2dn(&p[2], &p[6], &p[10], &p[14]);
+    strDCT2x2dn(&p[3], &p[7], &p[11], &p[15]);
+}