This file provides the utilities.

shift2angle

This method converts the displacement to refraction angle.

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BOSlib.utils.shift2angle(shift: np.ndarray, ref_array: np.ndarray, sensor_pitch: float, resolution_of_background: float, Lb: float, Lci: float, binarization : str ="HPfilter", thresh : int = 128, freq : int = 500)

    """
    Convert the background image displacement to the angle of light refraction.

    Parameters
    ----------
    shift : np.ndarray
        Displacement values from the background image.
    ref_array : np.ndarray
        Reference image array used for calculations.
    sensor_pitch : float
        The pitch of the image sensor in mm.
    resolution_of_background : float
        It represents the number of lines per mm.
    Lb : float
        Distance from the background to the object being captured(mm).
    Lci : float
        Distance from the image sensor to the object being captured(mm).
    
    binarization : str, optional, default="HPfilter"
        The method used for binarization of the images. Options are:
        - "thresh" : Use thresholding for binarization.
        - "HPfilter" : Use high-pass filtering for binarization.
        
    thresh : int, optional, default=128
        The threshold value used for binarization when `binarization="thresh"`. Pixels with values above the threshold are set to 1, and those below are set to 0.
        
    freq : int, optional, default=500
        The frequency parameter used for high-pass filtering when `binarization="HPfilter"`.

    Returns
    -------
    tuple
        - angle : np.ndarray
            The calculated angles of light refraction.
        - Lc : float
            The distance from the object to the lens.
        - Li : float
            The distance from the lens to the image sensor.
        - projection_ratio : float
            The ratio of projection based on the dimensions.
    """

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Note:

Examples:

from BOSlib.utils import shift2angle
angle,Lc,Li,Projection_Ratio=shift2angle(shift = shift, ref_array = ref_image, sensor_pitch = 0.004220546, resolution_of_background = 10, Lb = 30, Lci = 532)

print(Lc,Li,Projecction_Ratio)

plt.figure(figsize=(10, 5))
plt.subplot(1, 2, 1)
plt.imshow(shift, cmap="gray")
plt.colorbar()
plt.title("Reference Image")
plt.axis("off")

plt.subplot(1, 2, 2)
plt.imshow(angle, cmap="gray")
plt.colorbar()
plt.title("Experimental Image")
plt.axis("off")

plt.show()

Output:

0.27733443890895615 0.2546655610910439 0.8286268274883615

get_gladstone_dale_constant

This method calculate Gladstone-Dale constant that is necessary to convert refractive index to density.

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BOSlib.utils.get_gladstone_dale_constant(temperature, pressure, humidity)

"""
    Calculate the Gladstone-Dale constant based on temperature, pressure, and humidity without using metpy.

    Parameters
    ----------
    temperature : float
        Temperature in degrees Celsius (°C).
    pressure : float
        Pressure in hectopascals (hPa).
    humidity : float
        Humidity as a percentage (%).

    Returns
    -------
    tuple
        - G : float
            The calculated Gladstone-Dale constant.
        - density : float
            The density of the atmosphere.
    """

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Note:

We are assuming an ideal gas

Examples: