print image files to thermal printer ESC-POS on stdout

esc-pos-image.py

#!/usr/bin/env python3
# esc-pos-image.py - print image files given as command line arguments
#                    to simple ESC-POS image on stdout
# scruss - 2014-07-26 - WTFPL (srsly)
#        - 2021-01-09 (made python3 compatible - tvm Carko!)

# if you want a proper CUPS driver for a 58mm thermal printer
# that uses this command set, go here:
#            https://github.com/klirichek/zj-58

import sys
from PIL import Image
import PIL.ImageOps
import struct

# give usage and exit if no arguments
if (len(sys.argv) == 1):
    print('Usage:', sys.argv[0],
          'image1 image2 ... [ > printer_device ]')
    exit(1)

# print all of the images!
for i in sys.argv[1:]:
    im = Image.open(i)

    # if image is not 1-bit, convert it
    if (im.mode != '1'):
        im = im.convert('1')

    # if image width is not a multiple of 8 pixels, fix that
    if (im.size[0] % 8):
        im2 = Image.new('1', (im.size[0] + 8 - im.size[0] % 8,
                              im.size[1]), 'white')
        im2.paste(im, (0, 0))
        im = im2

    # Invert image, via greyscale for compatibility
    #  (no, I don't know why I need to do this)
    im = PIL.ImageOps.invert(im.convert('L'))
    # ... and now convert back to single bit
    im = im.convert('1')

    # output header (GS v 0 \000), width, height, image data
    sys.stdout.buffer.write(b''.join((bytearray(b'\x1d\x76\x30\x00'),
                                      struct.pack('2B', int(im.size[0] / 8) % 256,
                                                  int(im.size[0] / (8 * 256))),
                                      struct.pack('2B', im.size[1] % 256,
                                                  int(im.size[1] / 256)),
                                      im.tobytes())))

Very lovely! Worked like nothing has ever have before in blueooth.

Very lovely! Worked like nothing has ever have before in bluetooth.

Glad you like it! One day I'll update it to Python 3, but the bytes vs utf8 bit seems like work

I made some changes to make it work with Pyton 3: https://gist.github.com/Carko/1507260d13eaa3e7cea6cecb713caca0

Much appreciated, Carko!

It really worked for me. I have used here.
Thanks!!!

It really worked for me. I have used here. Thanks!!!

That's really neat! I saw those little printers and wondered how well they would work.

this was very helpful for my project with an ESC/POS ZJ-58 thermal printer :)

I had problems with images of specific resolutions (384x288 broke, while 384x289 worked fine) using this script (I think this was the problem, I added a row of pixels to the former image and it worked ok). The image would print once, and then break and print the raw data as ASCII.

So, I started using the https://github.com/python-escpos/python-escpos/ Python library. But thanks for this gist and the blog posts! they got me started really well :)

I had problems with images of specific resolutions (384x288 broke, while 384x289 worked fine)

Hey, thanks! I'm probably not finishing off the last line properly, so maybe data is getting corrupted. I haven't really done anything with this gist in a long time.

python-escpos didn't used to work for me, so I'm glad to see that it's getting some attention

python-escpos didn't used to work for me, so I'm glad to see that it's getting some attention

it works for me, but maybe a bit too well... and by that I mean running python-escpos takes over control of the USB device and never hands it back (even using close()), so I can't use the simple printf "hi\n\n\n" > /dev/usb/lp0 after using it, and have to restart the printer to do so. Ah well, I guess I will do everything using the python library... >:(