Saving a png image to json file in python

Question

I need to save a png image to a json file in python. In addition, the beginning of the json file must look like this:

{"image":"data:image/jpeg;base64,/etc.

I suspect that this means that I also need to convert it into jpeg format.

This is what I've tried this far:

import base64, json

filename = 'example_png.png'
f = open(filename, 'rb')
img_data = f.read()
f.close()
enc_data = base64.b64encode(img_data)

json.dump({'image':enc_data}, open('example_png.json', 'w'))

This resulted in the the following error: TypeError: Object of type bytes is not JSON serializable

I've also played around with decoding. For example, I added

enc_data = enc_data.decode('utf-8')

before saving to the json file. Then something was saved to the file, but obviously not in the right format.

I would be really grateful for any help.

Answer 1

Try:

import base64
import json

filename = "your_image.png"

with open(filename, "rb") as f_in, open("example_png.json", "w") as f_out:
    enc_data = base64.b64encode(f_in.read()).decode("utf-8")
    json.dump({"image": f"data:image/png;base64,{enc_data}"}, f_out)

---

EDIT: To convert the image to Jpeg and save it to Json you can use Pillow module:

import base64
import json
from io import BytesIO

from PIL import Image

filename = "<your image.jpg|png>"

with open("example_png_jpeg.json", "w") as f_out:
    png_image = Image.open(filename)
    jpg_buffer = BytesIO()
    png_image.save(jpg_buffer, format="JPEG")

    enc_data = base64.b64encode(jpg_buffer.getvalue()).decode("utf-8")
    json.dump({"image": f"data:image/jpeg;base64,{enc_data}"}, f_out)