Merge pull request #2730 from uploadcare/fast-geometry

Faster Transposition

PIL/Image.py

@@ -150,6 +150,7 @@ ROTATE_90 = 2
 ROTATE_180 = 3
 ROTATE_270 = 4
 TRANSPOSE = 5
+TRANSVERSE = 6
 
 # transforms
 AFFINE = 0
@@ -2173,8 +2174,8 @@ class Image(object):
 
         :param method: One of :py:attr:`PIL.Image.FLIP_LEFT_RIGHT`,
           :py:attr:`PIL.Image.FLIP_TOP_BOTTOM`, :py:attr:`PIL.Image.ROTATE_90`,
-          :py:attr:`PIL.Image.ROTATE_180`, :py:attr:`PIL.Image.ROTATE_270` or
+          :py:attr:`PIL.Image.ROTATE_180`, :py:attr:`PIL.Image.ROTATE_270`,
-          :py:attr:`PIL.Image.TRANSPOSE`.
+          :py:attr:`PIL.Image.TRANSPOSE` or :py:attr:`PIL.Image.TRANSVERSE`.
         :returns: Returns a flipped or rotated copy of this image.
         """
 

Tests/test_image_transpose.py

@@ -2,7 +2,7 @@ import helper
 from helper import unittest, PillowTestCase
 
 from PIL.Image import (FLIP_LEFT_RIGHT, FLIP_TOP_BOTTOM, ROTATE_90, ROTATE_180,
-                       ROTATE_270, TRANSPOSE)
+                       ROTATE_270, TRANSPOSE, TRANSVERSE)
 
 
 class TestImageTranspose(PillowTestCase):
@@ -108,6 +108,22 @@ class TestImageTranspose(PillowTestCase):
         for mode in ("L", "RGB"):
             transpose(mode)
 
+    def test_tranverse(self):
+        def transpose(mode):
+            im = self.hopper[mode]
+            out = im.transpose(TRANSVERSE)
+            self.assertEqual(out.mode, mode)
+            self.assertEqual(out.size, im.size[::-1])
+
+            x, y = im.size
+            self.assertEqual(im.getpixel((1, 1)), out.getpixel((y-2, x-2)))
+            self.assertEqual(im.getpixel((x-2, 1)), out.getpixel((y-2, 1)))
+            self.assertEqual(im.getpixel((1, y-2)), out.getpixel((1, x-2)))
+            self.assertEqual(im.getpixel((x-2, y-2)), out.getpixel((1, 1)))
+
+        for mode in ("L", "RGB"):
+            transpose(mode)
+
     def test_roundtrip(self):
         im = self.hopper['L']
 
@@ -124,6 +140,12 @@ class TestImageTranspose(PillowTestCase):
             im.transpose(TRANSPOSE), transpose(ROTATE_90, FLIP_TOP_BOTTOM))
         self.assert_image_equal(
             im.transpose(TRANSPOSE), transpose(ROTATE_270, FLIP_LEFT_RIGHT))
+        self.assert_image_equal(
+            im.transpose(TRANSVERSE), transpose(ROTATE_90, FLIP_LEFT_RIGHT))
+        self.assert_image_equal(
+            im.transpose(TRANSVERSE), transpose(ROTATE_270, FLIP_TOP_BOTTOM))
+        self.assert_image_equal(
+            im.transpose(TRANSVERSE), transpose(ROTATE_180, TRANSPOSE))
 
 
 if __name__ == '__main__':

_imaging.c

@@ -1678,6 +1678,7 @@ _transpose(ImagingObject* self, PyObject* args)
     case 2: /* rotate 90 */
     case 4: /* rotate 270 */
     case 5: /* transpose */
+    case 6: /* transverse */
         imOut = ImagingNewDirty(imIn->mode, imIn->ysize, imIn->xsize);
         break;
     default:
@@ -1705,6 +1706,9 @@ _transpose(ImagingObject* self, PyObject* args)
         case 5:
             (void) ImagingTranspose(imOut, imIn);
             break;
+        case 6:
+            (void) ImagingTransverse(imOut, imIn);
+            break;
         }
 
     return PyImagingNew(imOut);

libImaging/Geometry.c

@@ -5,7 +5,8 @@
    Rotating in chunks that fit in the cache can speed up rotation
    8x on a modern CPU. A chunk size of 128 requires only 65k and is large enough
    that the overhead from the extra loops are not apparent. */
-#define ROTATE_CHUNK 128
+#define ROTATE_CHUNK 512
+#define ROTATE_SMALL_CHUNK 8
 
 #define COORD(v) ((v) < 0.0 ? -1 : ((int)(v)))
 #define FLOOR(v) ((v) < 0.0 ? ((int)floor(v)) : ((int)(v)))
@@ -26,30 +27,27 @@ ImagingFlipLeftRight(Imaging imOut, Imaging imIn)
 
     ImagingCopyInfo(imOut, imIn);
 
+#define FLIP_LEFT_RIGHT(INT, image) \
+    for (y = 0; y < imIn->ysize; y++) { \
+        INT* in = imIn->image[y]; \
+        INT* out = imOut->image[y]; \
+        xr = imIn->xsize-1; \
+        for (x = 0; x < imIn->xsize; x++, xr--) \
+            out[xr] = in[x]; \
+    }
+
     ImagingSectionEnter(&cookie);
 
     if (imIn->image8) {
-        for (y = 0; y < imIn->ysize; y++) {
+        FLIP_LEFT_RIGHT(UINT8, image8)
-            UINT8* in = (UINT8*) imIn->image8[y];
-            UINT8* out = (UINT8*) imOut->image8[y];
-            x = 0;
-            xr = imIn->xsize-1;
-            for (; x < imIn->xsize; x++, xr--)
-                out[xr] = in[x];
-        }
     } else {
-        for (y = 0; y < imIn->ysize; y++) {
+        FLIP_LEFT_RIGHT(INT32, image32)
-            UINT32* in = (UINT32*) imIn->image32[y];
-            UINT32* out = (UINT32*) imOut->image32[y];
-            x = 0;
-            xr = imIn->xsize-1;
-            for (; x < imIn->xsize; x++, xr--)
-                out[xr] = in[x];
-        }
     }
 
     ImagingSectionLeave(&cookie);
 
+#undef FLIP_LEFT_RIGHT
+
     return imOut;
 }
 
@@ -84,6 +82,7 @@ ImagingRotate90(Imaging imOut, Imaging imIn)
 {
     ImagingSectionCookie cookie;
     int x, y, xx, yy, xr, xxsize, yysize;
+    int xxx, yyy, xxxsize, yyysize;
 
     if (!imOut || !imIn || strcmp(imIn->mode, imOut->mode) != 0)
         return (Imaging) ImagingError_ModeError();
@@ -92,15 +91,22 @@ ImagingRotate90(Imaging imOut, Imaging imIn)
 
     ImagingCopyInfo(imOut, imIn);
 
-#define ROTATE_90(image) \
+#define ROTATE_90(INT, image) \
     for (y = 0; y < imIn->ysize; y += ROTATE_CHUNK) { \
         for (x = 0; x < imIn->xsize; x += ROTATE_CHUNK) { \
             yysize = y + ROTATE_CHUNK < imIn->ysize ? y + ROTATE_CHUNK : imIn->ysize; \
             xxsize = x + ROTATE_CHUNK < imIn->xsize ? x + ROTATE_CHUNK : imIn->xsize; \
-            for (yy = y; yy < yysize; yy++) { \
+            for (yy = y; yy < yysize; yy += ROTATE_SMALL_CHUNK) { \
-                xr = imIn->xsize - 1 - x; \
+                for (xx = x; xx < xxsize; xx += ROTATE_SMALL_CHUNK) { \
-                for (xx = x; xx < xxsize; xx++, xr--) { \
+                    yyysize = yy + ROTATE_SMALL_CHUNK < imIn->ysize ? yy + ROTATE_SMALL_CHUNK : imIn->ysize; \
-                    imOut->image[xr][yy] = imIn->image[yy][xx]; \
+                    xxxsize = xx + ROTATE_SMALL_CHUNK < imIn->xsize ? xx + ROTATE_SMALL_CHUNK : imIn->xsize; \
+                    for (yyy = yy; yyy < yyysize; yyy++) { \
+                        INT* in = imIn->image[yyy]; \
+                        xr = imIn->xsize - 1 - xx; \
+                        for (xxx = xx; xxx < xxxsize; xxx++, xr--) { \
+                            imOut->image[xr][yyy] = in[xxx]; \
+                        } \
+                    } \
                 } \
             } \
         } \
@@ -109,9 +115,9 @@ ImagingRotate90(Imaging imOut, Imaging imIn)
     ImagingSectionEnter(&cookie);
 
     if (imIn->image8)
-        ROTATE_90(image8)
+        ROTATE_90(UINT8, image8)
     else
-        ROTATE_90(image32)
+        ROTATE_90(INT32, image32)
 
     ImagingSectionLeave(&cookie);
 
@@ -126,6 +132,7 @@ ImagingTranspose(Imaging imOut, Imaging imIn)
 {
     ImagingSectionCookie cookie;
     int x, y, xx, yy, xxsize, yysize;
+    int xxx, yyy, xxxsize, yyysize;
 
     if (!imOut || !imIn || strcmp(imIn->mode, imOut->mode) != 0)
         return (Imaging) ImagingError_ModeError();
@@ -134,14 +141,21 @@ ImagingTranspose(Imaging imOut, Imaging imIn)
 
     ImagingCopyInfo(imOut, imIn);
 
-#define TRANSPOSE(image) \
+#define TRANSPOSE(INT, image) \
     for (y = 0; y < imIn->ysize; y += ROTATE_CHUNK) { \
         for (x = 0; x < imIn->xsize; x += ROTATE_CHUNK) { \
             yysize = y + ROTATE_CHUNK < imIn->ysize ? y + ROTATE_CHUNK : imIn->ysize; \
             xxsize = x + ROTATE_CHUNK < imIn->xsize ? x + ROTATE_CHUNK : imIn->xsize; \
-            for (yy = y; yy < yysize; yy++) { \
+            for (yy = y; yy < yysize; yy += ROTATE_SMALL_CHUNK) { \
-                for (xx = x; xx < xxsize; xx++) { \
+                for (xx = x; xx < xxsize; xx += ROTATE_SMALL_CHUNK) { \
-                    imOut->image[xx][yy] = imIn->image[yy][xx]; \
+                    yyysize = yy + ROTATE_SMALL_CHUNK < imIn->ysize ? yy + ROTATE_SMALL_CHUNK : imIn->ysize; \
+                    xxxsize = xx + ROTATE_SMALL_CHUNK < imIn->xsize ? xx + ROTATE_SMALL_CHUNK : imIn->xsize; \
+                    for (yyy = yy; yyy < yyysize; yyy++) { \
+                        INT* in = imIn->image[yyy]; \
+                        for (xxx = xx; xxx < xxxsize; xxx++) { \
+                            imOut->image[xxx][yyy] = in[xxx]; \
+                        } \
+                    } \
                 } \
             } \
         } \
@@ -150,9 +164,9 @@ ImagingTranspose(Imaging imOut, Imaging imIn)
     ImagingSectionEnter(&cookie);
 
     if (imIn->image8)
-        TRANSPOSE(image8)
+        TRANSPOSE(UINT8, image8)
     else
-        TRANSPOSE(image32)
+        TRANSPOSE(INT32, image32)
 
     ImagingSectionLeave(&cookie);
 
@@ -162,6 +176,57 @@ ImagingTranspose(Imaging imOut, Imaging imIn)
 }
 
 
+Imaging
+ImagingTransverse(Imaging imOut, Imaging imIn)
+{
+    ImagingSectionCookie cookie;
+    int x, y, xr, yr, xx, yy, xxsize, yysize;
+    int xxx, yyy, xxxsize, yyysize;
+
+    if (!imOut || !imIn || strcmp(imIn->mode, imOut->mode) != 0)
+        return (Imaging) ImagingError_ModeError();
+    if (imIn->xsize != imOut->ysize || imIn->ysize != imOut->xsize)
+        return (Imaging) ImagingError_Mismatch();
+
+    ImagingCopyInfo(imOut, imIn);
+
+#define TRANSVERSE(INT, image) \
+    for (y = 0; y < imIn->ysize; y += ROTATE_CHUNK) { \
+        for (x = 0; x < imIn->xsize; x += ROTATE_CHUNK) { \
+            yysize = y + ROTATE_CHUNK < imIn->ysize ? y + ROTATE_CHUNK : imIn->ysize; \
+            xxsize = x + ROTATE_CHUNK < imIn->xsize ? x + ROTATE_CHUNK : imIn->xsize; \
+            for (yy = y; yy < yysize; yy += ROTATE_SMALL_CHUNK) { \
+                for (xx = x; xx < xxsize; xx += ROTATE_SMALL_CHUNK) { \
+                    yyysize = yy + ROTATE_SMALL_CHUNK < imIn->ysize ? yy + ROTATE_SMALL_CHUNK : imIn->ysize; \
+                    xxxsize = xx + ROTATE_SMALL_CHUNK < imIn->xsize ? xx + ROTATE_SMALL_CHUNK : imIn->xsize; \
+                    yr = imIn->ysize - 1 - yy; \
+                    for (yyy = yy; yyy < yyysize; yyy++, yr--) { \
+                        INT* in = imIn->image[yyy]; \
+                        xr = imIn->xsize - 1 - xx; \
+                        for (xxx = xx; xxx < xxxsize; xxx++, xr--) { \
+                            imOut->image[xr][yr] = in[xxx]; \
+                        } \
+                    } \
+                } \
+            } \
+        } \
+    }
+
+    ImagingSectionEnter(&cookie);
+
+    if (imIn->image8)
+        TRANSVERSE(UINT8, image8)
+    else
+        TRANSVERSE(INT32, image32)
+
+    ImagingSectionLeave(&cookie);
+
+#undef TRANSVERSE
+
+    return imOut;
+}
+
+
 Imaging
 ImagingRotate180(Imaging imOut, Imaging imIn)
 {
@@ -175,20 +240,23 @@ ImagingRotate180(Imaging imOut, Imaging imIn)
 
     ImagingCopyInfo(imOut, imIn);
 
-#define ROTATE_180(image)\
+#define ROTATE_180(INT, image) \
     for (y = 0; y < imIn->ysize; y++, yr--) { \
+        INT* in = imIn->image[y]; \
+        INT* out = imOut->image[yr]; \
         xr = imIn->xsize-1; \
         for (x = 0; x < imIn->xsize; x++, xr--) \
-            imOut->image[y][x] = imIn->image[yr][xr];\
+            out[xr] = in[x]; \
     }
 
     ImagingSectionEnter(&cookie);
 
     yr = imIn->ysize-1;
-    if (imIn->image8)
+    if (imIn->image8) {
-        ROTATE_180(image8)
+        ROTATE_180(UINT8, image8)
-    else
+    } else {
-        ROTATE_180(image32)
+        ROTATE_180(INT32, image32)
+    }
 
     ImagingSectionLeave(&cookie);
 
@@ -203,6 +271,7 @@ ImagingRotate270(Imaging imOut, Imaging imIn)
 {
     ImagingSectionCookie cookie;
     int x, y, xx, yy, yr, xxsize, yysize;
+    int xxx, yyy, xxxsize, yyysize;
 
     if (!imOut || !imIn || strcmp(imIn->mode, imOut->mode) != 0)
         return (Imaging) ImagingError_ModeError();
@@ -211,15 +280,22 @@ ImagingRotate270(Imaging imOut, Imaging imIn)
 
     ImagingCopyInfo(imOut, imIn);
 
-#define ROTATE_270(image) \
+#define ROTATE_270(INT, image) \
     for (y = 0; y < imIn->ysize; y += ROTATE_CHUNK) { \
         for (x = 0; x < imIn->xsize; x += ROTATE_CHUNK) { \
             yysize = y + ROTATE_CHUNK < imIn->ysize ? y + ROTATE_CHUNK : imIn->ysize; \
             xxsize = x + ROTATE_CHUNK < imIn->xsize ? x + ROTATE_CHUNK : imIn->xsize; \
-            yr = imIn->ysize - 1 - y; \
+            for (yy = y; yy < yysize; yy += ROTATE_SMALL_CHUNK) { \
-            for (yy = y; yy < yysize; yy++, yr--) { \
+                for (xx = x; xx < xxsize; xx += ROTATE_SMALL_CHUNK) { \
-                for (xx = x; xx < xxsize; xx++) { \
+                    yyysize = yy + ROTATE_SMALL_CHUNK < imIn->ysize ? yy + ROTATE_SMALL_CHUNK : imIn->ysize; \
-                    imOut->image[xx][yr] = imIn->image[yy][xx]; \
+                    xxxsize = xx + ROTATE_SMALL_CHUNK < imIn->xsize ? xx + ROTATE_SMALL_CHUNK : imIn->xsize; \
+                    yr = imIn->ysize - 1 - yy; \
+                    for (yyy = yy; yyy < yyysize; yyy++, yr--) { \
+                        INT* in = imIn->image[yyy]; \
+                        for (xxx = xx; xxx < xxxsize; xxx++) { \
+                            imOut->image[xxx][yr] = in[xxx]; \
+                        } \
+                    } \
                 } \
             } \
         } \
@@ -228,9 +304,9 @@ ImagingRotate270(Imaging imOut, Imaging imIn)
     ImagingSectionEnter(&cookie);
 
     if (imIn->image8)
-        ROTATE_270(image8)
+        ROTATE_270(UINT8, image8)
     else
-        ROTATE_270(image32)
+        ROTATE_270(INT32, image32)
 
     ImagingSectionLeave(&cookie);
 

libImaging/Imaging.h

@@ -289,8 +289,9 @@ extern Imaging ImagingRankFilter(Imaging im, int size, int rank);
 extern Imaging ImagingRotate90(Imaging imOut, Imaging imIn);
 extern Imaging ImagingRotate180(Imaging imOut, Imaging imIn);
 extern Imaging ImagingRotate270(Imaging imOut, Imaging imIn);
-extern Imaging ImagingResample(Imaging imIn, int xsize, int ysize, int filter, float box[4]);
 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 ImagingTransform(
     Imaging imOut, Imaging imIn, int method, int x0, int y0, int x1, int y1,
     double *a, int filter, int fill);