_image_utils.py

import os

from PIL import Image
from mtlogger import logger

from _settings import (
  LONG_STRIP_ASPECT_RATIO,
  MAX_HEIGHT,
  MAX_WIDTH,
  OUTPUT_FORMAT,
  OUTPUT_EXTENSION,
  OUTPUT_QUALITY,
  WEBP_METHOD,
)

JPEG_EXTENSION = '.jpeg'
JPG_EXTENSION = '.jpg'
PNG_EXTENSION = '.png'
WEBP_EXTENSION = '.webp'

FILE_EXCLUSIONS = ['folder.jpg', 'cover.jpg']


def is_image_file(
  filename: str,
):
  name = filename.lower()
  return (
    name.endswith(
      (JPG_EXTENSION, JPEG_EXTENSION, PNG_EXTENSION, WEBP_EXTENSION)
    )
    and name not in FILE_EXCLUSIONS
  )


def is_image_uncompressed(
  filename: str,
):
  return filename.lower().endswith(PNG_EXTENSION)


def is_image_optimally_compressed(
  filename: str,
):
  return filename.lower().endswith(WEBP_EXTENSION)


def get_max_dimensions(
  img: Image.Image,
):
  width, height = img.size

  aspect_ratio = width / height
  height_ratio = height / MAX_HEIGHT
  width_ratio = width / MAX_WIDTH
  is_portrait = height > width
  is_long_strip = aspect_ratio <= LONG_STRIP_ASPECT_RATIO
  too_wide = width > MAX_WIDTH and is_portrait
  too_tall = height > MAX_HEIGHT and not is_long_strip

  if too_wide and width_ratio > height_ratio:
    width = MAX_WIDTH
    height = int(width / aspect_ratio)
  elif too_tall:
    height = MAX_HEIGHT
    width = int(height * aspect_ratio)
  else:
    return None

  return (width, height)


def image_needs_resizing(
  img: Image.Image,
):
  return get_max_dimensions(img) is not None


def resize_image(
  img: Image.Image,
):
  new_dimensions = get_max_dimensions(img)
  if new_dimensions:
    return img.resize(new_dimensions, Image.LANCZOS)
  return img


def save_image_to_path(
  img: Image.Image,
  original_img_path: str,
  keep=False,
):
  try:
    output_img_path = (
      f'{os.path.splitext(original_img_path)[0]}.{OUTPUT_EXTENSION}'
    )
    save_options = {'quality': OUTPUT_QUALITY}
    if OUTPUT_FORMAT.upper() == 'WEBP':
      save_options['method'] = WEBP_METHOD
    img.save(output_img_path, OUTPUT_FORMAT, **save_options)
    if not keep and output_img_path != original_img_path:
      os.remove(original_img_path)

  except Exception as ex:
    logger.error(f'Error processing "{original_img_path}":\n{ex}')