image-intensities 0.0.10.dev3

Calculate image intensities, a database friendly alternative to image hashing..

image_intensities

Python implementation of the great derpibooru/image_intensities.

The algorithmic overview is to convert the image into the yuv colorspace, drop the u and v components, and then average the y component over 4 evenly-spaced rectangles on the image dimensions.

Usage

from image_intensities import png_intensities, jpeg_intensities
luma = png_intensities('/absolute/path/to/954482.png')  # image can ge found in the tests folder.
luma = jpeg_intensities('/absolute/path/to/2544057.jpg')  # image can ge found in the tests folder.

# returns something like
luma == Luma(nw=0.42, ne=0.44, sw=0.58, se=0.69) 

from image_intensities import rgb_luma_from_filename, Luma

luma = rgb_luma_from_filename('/path/to/image.png')

# returns something like
luma == Luma(nw=0.42, ne=0.44, sw=0.58, se=0.69)

Dependencies

C-Extension

libpng

• MacOS: brew install libpng (tested to work with 1.6.37)
• Ubuntu: sudo apt-get update && sudo apt-get install libpng-dev
• Dockerfile, Ubuntu based: apt-get update -y && apt-get install -y libpng-dev && apt-get clean && rm -rfv /var/lib/apt/lists/*

  • ⚠️ Make sure you pull a recent release of the python docker image (even if it's an older python version!). Especially if you're getting errors complaining about a png_set_longjmp_fn function when you try to use it. As time of writing the 2-month old version did not work, but the newest releases (python:3.6: 6ac87e65b6d0, pythong:3.9: 1b33974176a3) ones have that fixed.

Installation

See dependencies above, and make sure those are installed.

Install via pip

pip install image_intensities

Mac OS:

CPPFLAGS='-I/usr/local/include/' LDFLAGS='-L/usr/local/lib/' pip install image_intensities

From source

E.g. you checked out this repository:

python setup.py install

Mac OS:

CPPFLAGS='-I/usr/local/include/' LDFLAGS='-L/usr/local/lib/' python setup.py install

Minimal installation example

Using docker as it already has a working libpng-dev:

docker pull python:3.9
docker run -it --rm python:3.9 bash
pip install image_intensities

# test import
python -c"import image_intensities as it; print(it._intensities.ffi)"

# test with a png
wget https://derpicdn.net/img/download/2015/8/9/954482.png -O /tmp/954482.png
python -c"from image_intensities import png_intensities; print(png_intensities('/tmp/954482.png'))"

# test with a jpg
wget https://derpicdn.net/img/download/2021/2/4/2544057.jpg -O /tmp/2544057.jpg  # we need to use an absolute path!
python -c"from image_intensities import jpeg_intensities; print(jpeg_intensities('/tmp/2544057.jpg'))"