透视变换

EffectLab/Effect.py

@@ -34,6 +34,35 @@ def __call__(self, img):
     def filter(self, img):
         return img
 
+class PerspectiveWarpEffect(Effect):
+    '''透视变换
+    '''
+    def __init__(self,
+                 lefttopoffset=(0, 0),
+                 righttopoffset=(0, 0),
+                 rightbottomoffset=(0, 0),
+                 leftbottomoffset=(0, 0),
+                 ):
+        self.offsets = [lefttopoffset,
+                        righttopoffset,
+                        rightbottomoffset,
+                        leftbottomoffset,
+                        ]
+
+    def filter(self, im):
+        import cv, numpy
+
+        width, height = im.size
+        orig = [(0,0),(width - 1,0),(width - 1, height - 1),(0, height - 1)]
+        pos = map(lambda lhs, rhs: (lhs[0] + rhs[0], lhs[1] + rhs[1]), orig, self.offsets)
+
+        mat = cv.CreateMat(3, 3, cv.CV_32FC1)
+        cv.GetPerspectiveTransform(pos, orig, mat) 
+        a = numpy.asarray(mat) 
+
+        im = im.transform(im.size, Image.PERSPECTIVE, a.flatten(), Image.BILINEAR) 
+        return im
+
 
 class RegionWarpEffect(Effect):
     def __init__(self, formula, antialias=2, box=None):
@@ -253,44 +282,44 @@ def filter(self, img):
         warp = RegionWarpEffect(f, self.antialias)
         return warp(img)
 
-class WaveEffect(Effect):
-    name = 'Wave Effect'
-    def __init__(self, vertical_delta=0.1, horizon_delta=0, box=None):
-        self.vertical_delta = vertical_delta
-        self.horizon_delta = horizon_delta
-        self.box = box
-
-    def filter(self, img):
-        if self.box == None:
-            left, top = 0, 0
-            right, bottom = img.size[0] - 1, img.size[1] - 1
-        else:
-            left, top, right, bottom = self.box
-
-        width, height = img.size
-
-        mid_x = (right + left) / 2.0
-        mid_y = (top + bottom) / 2.0 
-
-        new_img = img.copy()
-        height_delta = (bottom - top + 1) * self.vertical_delta 
-        width_delta = 2 * math.pi / (right - left + 1) * (self.horizon_delta + 1)
-        for x in xrange(left, right):
-            degree = x * width_delta
-            for y in xrange(top, bottom):
-
-                # distortion
-                h = sin(degree) * height_delta * ((bottom - top) / 2 - sqrt((y - mid_y) ** 2 + (x - mid_x) ** 2)) / mid_y
-                offset = int(round(h))
-                _x = x
-                _y = y + offset
-
-                if 0 < x < width and 0 < _y < height:
-                    new_img.putpixel((x, y), img.getpixel((x, _y)))
-                else:
-                    new_img.putpixel((x, y), Effect.empty_color)
-
-        return new_img
+# class WaveEffect(Effect):
+#     name = 'Wave Effect'
+#     def __init__(self, vertical_delta=0.1, horizon_delta=0, box=None):
+#         self.vertical_delta = vertical_delta
+#         self.horizon_delta = horizon_delta
+#         self.box = box
+
+#     def filter(self, img):
+#         if self.box == None:
+#             left, top = 0, 0
+#             right, bottom = img.size[0] - 1, img.size[1] - 1
+#         else:
+#             left, top, right, bottom = self.box
+
+#         width, height = img.size
+
+#         mid_x = (right + left) / 2.0
+#         mid_y = (top + bottom) / 2.0 
+
+#         new_img = img.copy()
+#         height_delta = (bottom - top + 1) * self.vertical_delta 
+#         width_delta = 2 * math.pi / (right - left + 1) * (self.horizon_delta + 1)
+#         for x in xrange(left, right):
+#             degree = x * width_delta
+#             for y in xrange(top, bottom):
+
+#                 # distortion
+#                 h = sin(degree) * height_delta * ((bottom - top) / 2 - sqrt((y - mid_y) ** 2 + (x - mid_x) ** 2)) / mid_y
+#                 offset = int(round(h))
+#                 _x = x
+#                 _y = y + offset
+
+#                 if 0 < x < width and 0 < _y < height:
+#                     new_img.putpixel((x, y), img.getpixel((x, _y)))
+#                 else:
+#                     new_img.putpixel((x, y), Effect.empty_color)
+
+#         return new_img
 
 
 class EffectGlue(Effect):

TestEffectLab.py

@@ -39,13 +39,13 @@ def main():
     print 'Started'
 
     effects = [
-        RadianFormulaEffect(lambda r, phi: (r ** 2, phi), 4), 
+        LocalWarpEffect((50, 20), (80, 40), 30),
         RadianSqrtEffect(),
-        GlobalWaveEffect(),
         LensWarpEffect(lambda x, y: (sign(x) * x ** 2, sign(y) * y ** 2)),
+        RadianFormulaEffect(lambda r, phi: (r ** 2, phi), 4), 
+        GlobalWaveEffect(),
         LensWarpEffect(lambda x, y: (sin(x * math.pi / 2), sin(y * math.pi / 2))),
         RadianFormulaEffect(lambda r, phi: (r ** 1.5 * math.cos(r), phi)),
-        LocalWarpEffect((130, 120), (130, 50), 100),
                ] 
 
     # if os.path.exists('z.jpg'):