Public source code release

app/src/main/jni/libjpeg-turbo/cmyk.h

@@ -0,0 +1,61 @@
+/*
+ * cmyk.h
+ *
+ * Copyright (C) 2017-2018, 2022, D. R. Commander.
+ * For conditions of distribution and use, see the accompanying README.ijg
+ * file.
+ *
+ * This file contains convenience functions for performing quick & dirty
+ * CMYK<->RGB conversion.  This algorithm is suitable for testing purposes
+ * only.  Properly converting between CMYK and RGB requires a color management
+ * system.
+ */
+
+#ifndef CMYK_H
+#define CMYK_H
+
+#include <jinclude.h>
+#define JPEG_INTERNALS
+#include <jpeglib.h>
+#include "jsamplecomp.h"
+
+
+/* Fully reversible */
+
+INLINE
+LOCAL(void)
+rgb_to_cmyk(_JSAMPLE r, _JSAMPLE g, _JSAMPLE b,
+            _JSAMPLE *c, _JSAMPLE *m, _JSAMPLE *y, _JSAMPLE *k)
+{
+  double ctmp = 1.0 - ((double)r / (double)_MAXJSAMPLE);
+  double mtmp = 1.0 - ((double)g / (double)_MAXJSAMPLE);
+  double ytmp = 1.0 - ((double)b / (double)_MAXJSAMPLE);
+  double ktmp = MIN(MIN(ctmp, mtmp), ytmp);
+
+  if (ktmp == 1.0) ctmp = mtmp = ytmp = 0.0;
+  else {
+    ctmp = (ctmp - ktmp) / (1.0 - ktmp);
+    mtmp = (mtmp - ktmp) / (1.0 - ktmp);
+    ytmp = (ytmp - ktmp) / (1.0 - ktmp);
+  }
+  *c = (_JSAMPLE)((double)_MAXJSAMPLE - ctmp * (double)_MAXJSAMPLE + 0.5);
+  *m = (_JSAMPLE)((double)_MAXJSAMPLE - mtmp * (double)_MAXJSAMPLE + 0.5);
+  *y = (_JSAMPLE)((double)_MAXJSAMPLE - ytmp * (double)_MAXJSAMPLE + 0.5);
+  *k = (_JSAMPLE)((double)_MAXJSAMPLE - ktmp * (double)_MAXJSAMPLE + 0.5);
+}
+
+
+/* Fully reversible only for C/M/Y/K values generated with rgb_to_cmyk() */
+
+INLINE
+LOCAL(void)
+cmyk_to_rgb(_JSAMPLE c, _JSAMPLE m, _JSAMPLE y, _JSAMPLE k,
+            _JSAMPLE *r, _JSAMPLE *g, _JSAMPLE *b)
+{
+  *r = (_JSAMPLE)((double)c * (double)k / (double)_MAXJSAMPLE + 0.5);
+  *g = (_JSAMPLE)((double)m * (double)k / (double)_MAXJSAMPLE + 0.5);
+  *b = (_JSAMPLE)((double)y * (double)k / (double)_MAXJSAMPLE + 0.5);
+}
+
+
+#endif /* CMYK_H */