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Cannot convert base64 string into image

Can someone help me turn this base64 data into image? I don't know if it's because the data was not decoded properly or anything else. Here is how I decoded the data:
import base64
c_data = { the data in the link (string type) }
c_decoded = base64.b64decode(c_data)
But it gave the error Incorrect Padding so I followed some tutorials and tried different ways to decode the data.
c_decoded = base64.b64decode(c_data + '=' * (-len(c_data) % 4))
c_decoded = base64.b64decode(c_data + '=' * ((4 - len(c_data) % 4) % 4)
Both ways decoded the data without giving the error Incorrect Padding but now I can't turn the decoded data into image.
I have tried creating an empty png then write the decoded data into it:
from PIL import Image
with open('c.png', 'wb') as f:
f.write(c_decoded)
image = Image.open('c.png')
image.show()
It didn't work and gave the error: cannot identify image file 'c.png'
I have tried using BytesIO:
from PIL import Image
import io
from io import BytesIO
image = Image.open(io.BytesIO(c_decoded))
image.show()
Now it gave the error: cannot identify image file <_io.BytesIO object at 0x0000024082B20270>
Please help me.

Not sure if you definitely need a Python solution, or you just want help decoding your image like the first line of your question says, and you thought Python might be needed.
If the latter, you can just use ImageMagick in the Terminal:
cat YOURFILE.TXT | magick inline:- result.png
Or equivalently and avoiding "Useless Use of cat":
magick inline:- result.png < YOURFILE.TXT
If the former, you can use something like this (untested):
from urllib import request
with request.urlopen('data:image/png;base64,iVBORw0...') as response:
im = response.read()
Now im contains a PNG-encoded [^1] image, so you can either save to disk as such:
with open('result.png','wb') as f:
f.write(im)
Or, you can wrap it in a BytesIO and open into a PIL Image:
from io import BytesIO
from PIL import Image
pilImage = Image.open(BytesIO(im))
[^1]: Note that I have blindly assumed it is a PNG, it may be JPEG, so you should ideally look at the start of the DataURI to determine a suitable extension for saving your file.

Credit to #jps for explaining why my code didn't work. Check out #Mark Setchell solution for the reliable way of decoding base64 data (his code fixes my mistake that #jps pointed out)
So basically remove the [data:image/png;base64,] at the beginning of the base64 string because it is just the format of the data.
Change this:
c = "data:image/png;base64,iVBORw0KGgoAAAANSUh..."
to this:
c = "iVBORw0KGgoAAAANSUh..."
and now we can use
c_decoded = base64.b64decode(c)

conveting bytes to image using tinytag and PIL

I am using tinytags module in python to get the cover art of a mp3 file and want to display or store it. The return type of the variable is showing to be bytes. I have tried fumbling around with PIL using frombytes but to no avail. Is there any method to convert the bytes to image?
from tinytag import TinyTag
tag = TinyTag.get("03. Me, Myself & I.mp3", image=True)
img = tag.get_image()

I actually got a PNG image when I called tag.get_image() but I guess you might get a JPEG. Either way, you can wrap it in a BytesIO and open it with PIL/Pillow or display it. Carrying on from your code:
from PIL import Image
import io
...
im = tag.get_image()
# Make a PIL Image
pi = Image.open(io.BytesIO(im))
# Save as PNG, or JPEG
pi.save('cover.png')
# Display
pi.show()
Note that you don't have to use PIL/Pillow. You could look at the first few bytes and if they are a PNG signature (\x89PNG) save data as binary with PNG extension. If the signature is JPEG (\xff \xd8) save data as binary with JPEG extension.

Can't read second barcode in the same image file using pyzbar

I'm coding in Python 2.7 and I need to implement a process where I will read a PDF then obtain the image of the first page of the document, then from that image that contains two barcodes obtain the values of both. As of now these are the two functions I've been working on so far (I need to do a lot of polishing before I move this to an environment):
Python process to obtain the image from the PDF from a Tutorial:
from wand.image import Image as wi
pdf = wi(filename="test.pdf", resolution=300)
pdfImageTest = pdf.convert("png")
i=1
for img in pdfImage.sequence:
page = wi
(image = img)
page.save(filename="test"+str(i)+".png")
i+=1
Python process to read the barcodes from an image:
from pyzbar.pyzbar import decode
from PIL import Image
import cv2
import numpy
decodedObjects = decode(Image.open('test2.png'))
obj = decodedObjects
print(obj)
decodedObjects = decode(cv2.imread('test2.png'))
print(obj)
According to the documentation for decode function in pyzbar, the function will scan all the barcodes contained in the image but as of now for both cases I've used, I'm only obtaining the first barcode in the image. Is there a way to force the function to keep scanning the image or pointing it into a specific location of the image after finishing the process for the first image?

You should use obj.data and iterate over all objects.
Here's an example:
from pyzbar.pyzbar import decode
from PIL import Image
import cv2
import numpy
decodedObjects = decode(Image.open('test2.png'))
obj = decodedObjects
for bar in obj:
print(bar.data)
By the way, the print statement is replaced with print() function in Python 3. So if you strictly want to use Python 2.7, you should use e.g. print bar.data.

Get Base64 image dimension in python

Assuming one has a base64 encoded image.
How can one extract the image dimensions from the string, preferably without storing the string to disc as an image?
For PNG files, I can get this from bytes 16-24 of the string which are part of the PNG header, but for JPEG images, it appears no such hack exists.
What are some nice ways of getting the image dimensions in this case?

Using the pillow library one can do:
import io
import PIL
from PIL import Image
imgdata = base64.b64decode(base64_str)
im = Image.open(io.BytesIO(imgdata))
width, height = im.size

How to decode JPG/PNG in python?

This is a code of a JPG/PNG(I don't know exactly)
Here's on google docs
I need to decode it in Python to complete image and show it using Pillow or something like that. Do you know any libraries or ways how to decode it? Thanks!

(for Python 3)
If the image is stored as a binary file, open it directly:
import PIL
# Create Image object
picture = PIL.Image.open('picture_code.dat')
#display image
picture.show()
# print whether JPEG, PNG, etc.
print(picture.format)
If the image is stored as hex in a plaintext file picture_code.dat similar to your Google Docs link, it needs to first be converted to binary data:
import binascii
import PIL
import io
# Open plaintext file with hex
picture_hex = open('picture_code.dat').read()
# Convert hex to binary data
picture_bytes = binascii.unhexlify(picture_hex)
# Convert bytes to stream (file-like object in memory)
picture_stream = io.BytesIO(picture_bytes)
# Create Image object
picture = PIL.Image.open(picture_stream)
#display image
picture.show()
# print whether JPEG, PNG, etc.
print(picture.format)