Pil: Convert Bytearray to Image

PIL: Convert Bytearray to Image

If you manipulate with bytearrays, then you have to use io.BytesIO. Also you can read a file directly to a bytearray.

import os
import io
import PIL.Image as Image

from array import array

def readimage(path):
    count = os.stat(path).st_size / 2
    with open(path, "rb") as f:
        return bytearray(f.read())

bytes = readimage(path+extension)
image = Image.open(io.BytesIO(bytes))
image.save(savepath)

Open PIL image from byte file

You can try this:

image = Image.frombytes('RGBA', (128,128), image_data, 'raw')

Source Code:

def frombytes(mode, size, data, decoder_name="raw", *args):
    param mode: The image mode.
    param size: The image size.
    param data: A byte buffer containing raw data for the given mode.
    param decoder_name: What decoder to use.

Convert PIL Image to byte array?

Thanks everyone for your help.

Finally got it resolved!!

import io

img = Image.open(fh, mode='r')
roi_img = img.crop(box)

img_byte_arr = io.BytesIO()
roi_img.save(img_byte_arr, format='PNG')
img_byte_arr = img_byte_arr.getvalue()

With this i don't have to save the cropped image in my hard disc and I'm able to retrieve the byte array from a PIL cropped image.

How to convert byte array to image in python

You can generate a bytearray of dummy data representing a gradient like this:

import numpy as np

# Generate a left-right gradient 242 px wide by 266 pixels tall
ba = bytearray((np.arange(242) + np.zeros((266,1))).astype(np.uint8)) 

For reference, that array will contain data like this:

array([[  0.,   1.,   2., ..., 239., 240., 241.],
       [  0.,   1.,   2., ..., 239., 240., 241.],
       [  0.,   1.,   2., ..., 239., 240., 241.],
       ...,
       [  0.,   1.,   2., ..., 239., 240., 241.],
       [  0.,   1.,   2., ..., 239., 240., 241.],
       [  0.,   1.,   2., ..., 239., 240., 241.]])

And then make into a PIL/Pillow image like this:

from PIL import Image

# Convert bytearray "ba" to PIL Image, 'L' just means greyscale/lightness
im = Image.frombuffer('L', (242,266), ba, 'raw', 'L', 0, 1)

Then you can save the image like this:

im.save('result.png')

Documentation is here.

How to get image from bytes in Python?

Use the PIL module. More information in answers here: Decode image bytes data stream to JPEG

from PIL import Image
from io import BytesIO

with open('img.jpg', 'rb') as f:
    data = f.read()

    # Load image from BytesIO
    im = Image.open(BytesIO(data))

    # Display image
    im.show()

    # Save the image to 'result.FORMAT', using the image format
    im.save('result.{im_format}'.format(im_format=im.format))

Python PIL bytes to Image

That image is not formed of raw bytes - rather it is an encoded JPEG file.
Moreover, you are not parsing the ascii HEX representation of the stream into proper bytes:
that is, an "ff" sequence in that file is being passed to PIL as two c letters "f" instead of a byte with the number 255.

So, first, you decode the string to a proper byte sequence - sorry for the convolution - it is likely there is a better way to do that, but I am on a slow day:

data = urllib.urlopen("http://pastebin.ca/raw/2311595").read()
r_data = "".join(chr(int(data[i:i+2],16)) for i in range(0, len(data),2)) 

Ah, C.Y. posted on hte comment - this way:

>>> import binascii
>>> b_data = binascii.unhexlify(data)

And now, you import it to PIL as a JPEG image:

>>> from PIL import Image
>>> import cStringIO as StringIO
>>> stream = StringIO.StringIO(b_data)
>>> img = Image.open(stream)
>>> img.size
(320, 240)

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