dummy method

setup.py

@@ -39,6 +39,7 @@ _LIB_IMAGING = (
     "Access",
     "AlphaComposite",
     "Resample",
+    "Reduce",
     "Bands",
     "BcnDecode",
     "BitDecode",

src/PIL/Image.py

@@ -1887,6 +1887,22 @@ class Image(object):
 
         return self._new(self.im.resize(size, resample, box))
 
+    def reduce(self, factor):
+        """
+        Returns reduced in `factor` times copy of the image.
+        If the size of the image is not dividable by the `factor`,
+        the resulting size will be rounded up.
+
+        :param factor: A greater than 0 integer or tuple of two integers
+            for width and height separately.
+        """
+        if not isinstance(factor, (list, tuple)):
+            factor = (factor, factor)
+
+        self.load()
+
+        return self._new(self.im.reduce(factor))
+
     def rotate(
         self,
         angle,

src/_imaging.c

@@ -1829,6 +1829,28 @@ _resize(ImagingObject* self, PyObject* args)
     return PyImagingNew(imOut);
 }
 
+static PyObject*
+_reduce(ImagingObject* self, PyObject* args)
+{
+    Imaging imIn;
+    Imaging imOut;
+
+    int xscale, yscale;
+
+    imIn = self->image;
+
+    if (!PyArg_ParseTuple(args, "(ii)", &xscale, &yscale))
+        return NULL;
+
+    if (xscale < 1 || yscale < 1) {
+        return ImagingError_ValueError("scale must be > 0");
+    }
+
+    imOut = ImagingReduce(imIn, xscale, yscale);
+
+    return PyImagingNew(imOut);
+}
+
 
 #define IS_RGB(mode)\
     (!strcmp(mode, "RGB") || !strcmp(mode, "RGBA") || !strcmp(mode, "RGBX"))
@@ -3277,6 +3299,7 @@ static struct PyMethodDef methods[] = {
     {"rankfilter", (PyCFunction)_rankfilter, 1},
 #endif
     {"resize", (PyCFunction)_resize, 1},
+    {"reduce", (PyCFunction)_reduce, 1},
     {"transpose", (PyCFunction)_transpose, 1},
     {"transform2", (PyCFunction)_transform2, 1},
 

src/libImaging/Imaging.h

@@ -313,6 +313,7 @@ extern Imaging ImagingRotate270(Imaging imOut, Imaging imIn);
 extern Imaging ImagingTranspose(Imaging imOut, Imaging imIn);
 extern Imaging ImagingTransverse(Imaging imOut, Imaging imIn);
 extern Imaging ImagingResample(Imaging imIn, int xsize, int ysize, int filter, float box[4]);
+extern Imaging ImagingReduce(Imaging imIn, int xscale, int yscale);
 extern Imaging ImagingTransform(
     Imaging imOut, Imaging imIn, int method, int x0, int y0, int x1, int y1,
     double *a, int filter, int fill);

src/libImaging/Reduce.c

@@ -0,0 +1,16 @@
+#include "Imaging.h"
+
+#include <math.h>
+
+#define ROUND_UP(f) ((int) ((f) >= 0.0 ? (f) + 0.5F : (f) - 0.5F))
+
+
+Imaging
+ImagingReduce(Imaging imIn, int xscale, int yscale)
+{
+    Imaging imOut = NULL;
+
+    imOut = ImagingNewDirty(imIn->mode, imIn->xsize, imIn->ysize);
+
+    return imOut;
+}