add random crop effect

README.md

@@ -32,17 +32,18 @@ new config file and use it by `--config_file` option), here are some examples:
 |------------|----|
 |Origin(Font size 25)|![origin](./imgs/effects/origin.jpg)|
 |Perspective Transform|![perspective](./imgs/effects/perspective_transform.jpg)|
+|Random Crop|![rand_crop](./imgs/effects/random_crop.jpg)|
 |Curve|![curve](./imgs/effects/curve.jpg)|
-|Emboss|![emboss](./imgs/effects/emboss.jpg)|
 |Light border|![light border](./imgs/effects/light_border.jpg)|
 |Dark border|![dark border](./imgs/effects/dark_border.jpg)|
 |Random char space big|![random char space big](./imgs/effects/random_space_big.jpg)|
 |Random char space small|![random char space small](./imgs/effects/random_space_small.jpg)|
-|Reverse color|![reverse color](./imgs/effects/reverse.jpg)|
-|Blur|![blur](./imgs/effects/blur.jpg)|
 |Middle line|![middle line](./imgs/effects/line_middle.jpg)|
 |Table line|![table line](./imgs/effects/line_table.jpg)|
 |Under line|![under line](./imgs/effects/line_under.jpg)|
+|Emboss|![emboss](./imgs/effects/emboss.jpg)|
+|Reverse color|![reverse color](./imgs/effects/reverse.jpg)|
+|Blur|![blur](./imgs/effects/blur.jpg)|
 
 3. Run `main.py` file.
 

configs/default.yaml

@@ -20,6 +20,18 @@ curve:
   min: 1 # sin 函数的幅值范围
   max: 5
 
+# random crop text height
+crop:
+  enable: false
+  fraction: 0.5
+
+  # top and bottom will applied equally
+  top:
+    min: 5
+    max: 10 # in pixel, this value should small than img_height
+  bottom:
+    min: 5
+    max: 10 # in pixel, this value should small than img_height
 
 # Use image in bg_dir as background for text
 img_bg:
@@ -44,9 +56,9 @@ text_border:
 # https://docs.opencv.org/3.4/df/da0/group__photo__clone.html#ga2bf426e4c93a6b1f21705513dfeca49d
 # https://www.cs.virginia.edu/~connelly/class/2014/comp_photo/proj2/poisson.pdf
 # Use opencv seamlessClone() to draw text on background
-# This will make text image looks more natural
+# For some background image, this will make text image looks more real
 seamless_clone:
-  enable: true
+  enable: false
   fraction: 0.5
 
 perspective_transform:

textrenderer/renderer.py

@@ -49,9 +49,11 @@ def gen_img(self, img_index):
         # to make sure we can crop full word image after apply perspective
         bg = self.gen_bg(width=word_size[0] * 8, height=word_size[1] * 8)
         word_img, text_box_pnts, word_color = self.draw_text_on_bg(word, font, bg)
-
         self.dmsg("After draw_text_on_bg")
 
+        if apply(self.cfg.crop):
+            text_box_pnts = self.apply_crop(text_box_pnts, self.cfg.crop)
+
         if apply(self.cfg.line):
             word_img, text_box_pnts = self.liner.apply(word_img, text_box_pnts, word_color)
             self.dmsg("After draw line")
@@ -573,3 +575,29 @@ def apply_emboss(self, word_img):
 
     def apply_sharp(self, word_img):
         return cv2.filter2D(word_img, -1, self.sharp_kernel)
+
+    def apply_crop(self, text_box_pnts, crop_cfg):
+        """
+        Random crop text box height top or bottom, we don't need image information in this step, only change box pnts
+        :param text_box_pnts: bbox of text [left-top, right-top, right-bottom, left-bottom]
+        :param crop_cfg:
+        :return:
+            croped_text_box_pnts
+        """
+        height = abs(text_box_pnts[0][1] - text_box_pnts[3][1])
+        scale = float(height) / float(self.out_height)
+
+        croped_text_box_pnts = text_box_pnts
+
+        if prob(0.5):
+            top_crop = int(random.randint(crop_cfg.top.min, crop_cfg.top.max) * scale)
+            self.dmsg("top crop %d" % top_crop)
+            croped_text_box_pnts[0][1] += top_crop
+            croped_text_box_pnts[1][1] += top_crop
+        else:
+            bottom_crop = int(random.randint(crop_cfg.bottom.min, crop_cfg.bottom.max) * scale)
+            self.dmsg("bottom crop %d " % bottom_crop)
+            croped_text_box_pnts[2][1] -= bottom_crop
+            croped_text_box_pnts[3][1] -= bottom_crop
+
+        return croped_text_box_pnts