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@scruss
Last active June 19, 2024 11:32
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print image files to thermal printer ESC-POS on stdout
#!/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())))
@abhigkar
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It really worked for me. I have used here.
Thanks!!!

@scruss
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scruss commented Jul 12, 2023

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.

@alifeee
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alifeee commented Jun 7, 2024

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 :)

@scruss
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scruss commented Jun 8, 2024

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

@alifeee
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alifeee commented Jun 8, 2024

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... >:(

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