Using PIL to show image (png) in terminal

Question

Environment:

Python 3.7.2 Mac OS 10.14.3

I am try to find a way to show a image (jpg/png) in the terminal application.

And I found a working solution for jpg image here:

Display Images in Linux Terminal using Python

With the following code:

import numpy as np
from PIL import Image

def get_ansi_color_code(r, g, b):
    if r == g and g == b:
        if r < 8:
            return 16
        if r > 248:
            return 231
        return round(((r - 8) / 247) * 24) + 232
    return 16 + (36 * round(r / 255 * 5)) + (6 * round(g / 255 * 5)) + round(b / 255 * 5)

def get_color(r, g, b):
    return "\x1b[48;5;{}m \x1b[0m".format(int(get_ansi_color_code(r,g,b)))

def show_image(img_path):
    try:
        img = Image.open(img_path)
    except FileNotFoundError:
        exit('Image not found.')
    h = 100
    w = int((img.width / img.height) * h)
    img = img.resize((w, h), Image.ANTIALIAS)
    img_arr = np.asarray(img)

    for x in range(0, h):
        for y in range(0, w):
            pix = img_arr[x][y]
            print(get_color(pix[0], pix[1], pix[2]), sep='', end='')
        print()

if __name__ == '__main__':
    show_image(sys.argv[1])

The problem is when I try to use this code for a png file I get the error:

Traceback (most recent call last):
  File "img-viewer.py", line 62, in <module>
    show_image(sys.argv[1])
  File "img-viewer.py", line 40, in show_image
    print(get_color(pix[0], pix[1], pix[2]), sep='', end='')
IndexError: invalid index to scalar variable.

It seems like when processing a jpg file the pix is a tuple while with a png file the pix is a int value.

Any advice will be appreciated, thanks :)

Answer 1

Your image may be greyscale, or palettised. Either way there will only be 1 channel, not 3. So change this line

img = Image.open(img_path)

to

img = Image.open(img_path).convert('RGB')

so you get the 3 channels you expect and it all works nicely.

---

I noticed that your resizing code tries to keep the same aspect ratio in the resized image, which is all very laudable, but... the pixels on a Terminal are not actually square! If you look at the cursor up close, it is around 2x as tall as it is wide, so I changed the line of resizing code to allow for this:

w = int((img.width / img.height) * h) * 2

Keywords: PIL, Pillow, terminal, console, ANSI, escape sequences, graphics, ASCII art, image, image processing, Python