"SystemError: tile cannot extend outside image" in PIL during save image

Question

I have this Image =>

here is, all coordinates of above yellow boxes that is written in 3.txt file.

#Y   X Height     Width 

46 135 158 118 
46 281 163 104 
67 494 188 83 
70 372 194 101 
94 591 207 98 
252 132 238 123 
267 278 189 105 
320 741 69 141 
322 494 300 135 
323 389 390 124 
380 726 299 157 
392 621 299 108 
449 312 227 93 
481 161 425 150 
678 627 285 91 
884 13 650 437 
978 731 567 158 
983 692 60 43 
1402 13 157 114 

My intension is to crop those boxes and save all boxes as Image. I have written a code for that but getting error.

Here is my code =>

from PIL import Image
import matplotlib.pyplot as plt
import numpy as np
from os import listdir
#from scipy.misc import imsave

ARR = np.empty([1,4])
# print(ARR)

i = 0
k = 0
img = Image.open('3.png')

fo = open("3.txt", "r")
for line in fo:
    if not line.startswith('#'):
        for word in line.split():

            ARR[0][i] = int(word)
            print(int(word))
            # ARR[0][i] = int(word)
            i = i +1

    img2 = img.crop((int(ARR[0][1]), int(ARR[0][0]), int(ARR[0][0] + ARR[0][2]), int(ARR[0][1] + ARR[0][3])))
    name = "new-img" + str(k) + ".png"
    img2.save(name)
    k = k + 1
    i = 0

I am getting these error =>

Traceback (most recent call last): File "reshape.py", line 26, in img2.save(name) File "/usr/lib/python2.7/dist-packages/PIL/Image.py", line 1468, in save save_handler(self, fp, filename) File "/usr/lib/python2.7/dist-packages/PIL/PngImagePlugin.py", line 624, in _save ImageFile._save(im, _idat(fp, chunk), [("zip", (0,0)+im.size, 0, rawmode)]) File "/usr/lib/python2.7/dist-packages/PIL/ImageFile.py", line 462, in _save e.setimage(im.im, b) SystemError: tile cannot extend outside image

How do I fix these?

Beanie

The error states * tile cannot extend outside image*, which means you are trying to crop a region beyond the dimension of the image. Check whether the text file contains the correct coordinates. You might be confused with the coordinate system of images (I think). Do brush up on that before proceeding... – Shebat

Thanks, I think you are r8. @JeruLuke – Beanie

after doing this => img2 = img.crop((int(ARR[0][0]), int(ARR[0][1]), int(ARR[0][0] + ARR[0][2]), int(ARR[0][1] + ARR[0][3]))) it is working, Thanks @JeruLuke – Beanie

Amazing!! I made the same mistake in OpenCV many times – Shebat

Answer 1

With reference to the comments, the error occurred due to improper passing of the coordinates to PIL's crop() function.

As mentioned in the documentation, the function returns an image having taken in a tuple of four (x, y, width and height).

In the given text file the y coordinate is mentioned in the first column and x coordinate in the second column. The crop() function however accepts the value of x coordinate as the first parameter and the y coordinate as the second parameter.

The same applies for OpenCV as well.

Shebat

Pointing out that for me AmirHosseins answer actually was the correct one. The parameters are imageScreenshot.crop((x, y, x + width, y + height)) and not imageScreenshot.crop((x, y, width, height)) – Pram

The Pillow doc says both are correct, although I found the above answer to be working fine. – Manipur

I could not see such information in the corresponding document. It says "four coordinates; left, upper, right, lower". It means the function takes four coordinates of the region. Last two parameters are not width and height. Instead, x+width and y+height as explained in the document. Maybe people get consued because of other functions that take (x,y,width,height) (such as ImageDraw.rectangle). – Crowther

Answer 2

The mentioned way on the internet is like this:

imageScreenshot.crop((x, y, width, height))

But the correct way is this:

imageScreenshot.crop((x, y, x + width, y + height))

Meaning that you should add the x to the width and y to the height.
This is a simple example (driver is for python selenium):

def screenShotPart(x, y, width, height) -> str:
    screenshotBytes = driver.get_screenshot_as_png()
    imageScreenshot = Image.open(BytesIO(screenshotBytes))
    imageScreenshot = imageScreenshot.crop((x, y, x + width, y + height))
    imagePath = pathPrefix + "_____temp_" + str(time.time()).replace(".", "") + ".png"
    imageScreenshot.save(imagePath)

Hope it helps.

Extortionary

Answer 3

In my case the issue was that I was specifying start and end coordinates where the start X and start Y were not always less than the end X and Y. You cannot do this.

For example,

Start: (0, 50) End: (50, 0)

These coordinates make sense to me, but should actually be specified as:

Start: (0, 0) End: (50, 50)

Visually the same rectangle, but the latter is required for Pillow to crop.

Subarid

Answer 4

If you are using DeepLearning software to detect objects in image and you are trying to cut detections out - you will most likely see this

I had same error while using ImageAI for detecting objects in image. I've manage to resolve it by editing ImageFile.py from PIL package in my virtual environment.

ImageFile is located in

\home\myuser\anaconda3\envs\envsName\lib\python3.7\site-packages\PIL\ImageFile.py

Find _save function line that starts with:

def _save(im, fp, tile, bufsize=0):

After:

 tile.sort(key=_tilesort)
    # FIXME: make MAXBLOCK a configuration parameter
    # It would be great if we could have the encoder specify what it needs
    # But, it would need at least the image size in most cases. RawEncode is
    # a tricky case.

Insert:

tile = [e for e in tile if e[1][2] > 0 and e[1][3]>0]

This will skip saving of all detections which have incorrect sizes for width and height of image (tile) which is sometimes reported to be 0, probably because detected object is only partially shown on edge of the image.

------------

But if you for example have case where you know that all your images are 1920x1080 and you want to discard all images that are not reported with approximately same size than you can do something like this.

tile = [e for e in tile if e[1][2] > 1720 and e[1][3]>880]

width and height are reduced for 200px to allow smaller, maybe still correct images(tiles), to be saved and this will discard all other images.

Source.

Osmose

Answer 5

i faced same issue during cropping objects based on annotation txt but the code was correct not as they said above that:

imageScreenshot.crop((x, y, width, height))

should be

imageScreenshot.crop((x, y, x + width, y + height))

the error was in annotation valuse was 0 I edited the value and solved the issue

my code was

tmp = [x1, y1, x2, y2]
img2 = img.crop(tmp)
sav_path = 'valid/result' + '/' + l[0] + '/' + str(linec) + img_name[1] 
img2 = img2.save(sav_path)`

Semipostal