from matplotlib import pyplot as plt
import pydicom

from pylinac import image
from pylinac.core.io import retrieve_demo_file, TemporaryZipDirectory

demo_zip = retrieve_demo_file('drgs.zip')
with TemporaryZipDirectory(demo_zip) as tmpzip:
    image_files = image.retrieve_image_files(tmpzip)

    # read the values "raw"
    dmlc_raw = pydicom.read_file(image_files[0])
    open_raw = pydicom.read_file(image_files[1])
    raw = dmlc_raw.pixel_array / open_raw.pixel_array

    # Tag-correct the values
    img_dmlc = image.load(image_files[0])
    img_open = image.load(image_files[1])
    corrected = img_dmlc.array / img_open.array

plt.plot(raw[200, :], label="Raw DICOM pixels")
plt.plot(23*corrected[200, :], label="Using Rescale + Intercept Tags * 23")
plt.legend()
plt.grid(True)
plt.ylim(1.1, 1.6)
plt.show()