Add a gaussian blur drop shadow to an image. image - The image to overlay on top of the shadow. offset - Offset of the shadow from the image as an (x,y) tuple. Can be positive or negative. background - Background colour behind the image. shadow - Sha
( image, offset=(5,5), background=0xffffff, shadow=0x444444,
border=8, iterations=3)
| 7 | from PIL import Image, ImageFilter |
| 8 | |
| 9 | def dropShadow( image, offset=(5,5), background=0xffffff, shadow=0x444444, |
| 10 | border=8, iterations=3): |
| 11 | """ |
| 12 | Add a gaussian blur drop shadow to an image. |
| 13 | |
| 14 | image - The image to overlay on top of the shadow. |
| 15 | offset - Offset of the shadow from the image as an (x,y) tuple. Can be |
| 16 | positive or negative. |
| 17 | background - Background colour behind the image. |
| 18 | shadow - Shadow colour (darkness). |
| 19 | border - Width of the border around the image. This must be wide |
| 20 | enough to account for the blurring of the shadow. |
| 21 | iterations - Number of times to apply the filter. More iterations |
| 22 | produce a more blurred shadow, but increase processing time. |
| 23 | """ |
| 24 | |
| 25 | # Create the backdrop image -- a box in the background colour with a |
| 26 | # shadow on it. |
| 27 | totalWidth = image.size[0] + abs(offset[0]) + 2*border |
| 28 | totalHeight = image.size[1] + abs(offset[1]) + 2*border |
| 29 | back = Image.new(image.mode, (totalWidth, totalHeight), background) |
| 30 | |
| 31 | # Place the shadow, taking into account the offset from the image |
| 32 | shadowLeft = border + max(offset[0], 0) |
| 33 | shadowTop = border + max(offset[1], 0) |
| 34 | back.paste(shadow, [shadowLeft, shadowTop, shadowLeft + image.size[0], |
| 35 | shadowTop + image.size[1]] ) |
| 36 | |
| 37 | # Apply the filter to blur the edges of the shadow. Since a small kernel |
| 38 | # is used, the filter must be applied repeatedly to get a decent blur. |
| 39 | n = 0 |
| 40 | while n < iterations: |
| 41 | back = back.filter(ImageFilter.BLUR) |
| 42 | n += 1 |
| 43 | |
| 44 | # Paste the input image onto the shadow backdrop |
| 45 | imageLeft = border - min(offset[0], 0) |
| 46 | imageTop = border - min(offset[1], 0) |
| 47 | back.paste(image, (imageLeft, imageTop)) |
| 48 | |
| 49 | return back |
| 50 | |
| 51 | if __name__ == "__main__": |
| 52 | import sys |