Source code for pierogis.ingredients.resize

from typing import Union

import numpy as np
from PIL import Image

from .ingredient import Ingredient
from .pierogi import Pierogi


class Resize(Ingredient):
    """
    resize using width, height, and scale
    """
    FILTERS = {
        'default': Image.NEAREST,
        'nearest': Image.NEAREST,
        'box': Image.BOX,
        'bicubic': Image.BICUBIC,
        'bilinear': Image.BILINEAR,
        'hamming': Image.HAMMING,
        'lanczos': Image.LANCZOS,
    }

    def prep(
            self,
            width: int = None,
            height: int = None,
            scale: int = 1,
            resample: Union[int, str] = FILTERS['default'],
            **kwargs
    ):
        """
        if only one of width and height is provided,
        aspect ratio will be maintained.

        when reducing size,
        a dimension will round down if it would be a decimal

        cook 5x5 pixels prepped with a .5 scale -> resized to 2x2
        cook 2x3 pixels prepped with a width of 1 -> resized to 1x1

        :param width: width to resize to
        :param height: height to resize to
        :param scale: scale multiplier (2 means 2x)
        :param resample: resample filter to use
        """

        if width is None and height is None and scale is None:
            ValueError("One of width height or scale must be provided")

        self.width = width
        self.height = height
        self.scale = scale

        if resample in self.FILTERS:
            resample = self.FILTERS[resample]
        self.resample = resample

    def cook(self, pixels: np.ndarray):
        pierogi = Pierogi(pixels=pixels)

        width = pixels.shape[0]
        height = pixels.shape[1]

        if self.width is not None and self.height is not None:
            width = self.width
            height = self.height
        elif self.width is not None or self.height is not None:
            aspect = width / height

            if self.width is None:
                width = self.height * aspect
                height = self.height
            elif self.height is None:
                height = self.width / aspect
                width = self.width

        width *= self.scale
        height *= self.scale

        pierogi.resize(int(width), int(height), self.resample)

        return pierogi.pixels