The Python 3 implementation of the helper functions are in SF2_Python/helper.py and SF2_Python/helper_jpeg.py.
Some Python functions / methods are project work and they should not provided at the start of the SF2 project.
They are marked after the comment line:
############# Functions not provided initially #############in helpers.py and
############# Methods not provided initially #############in helpers_jpeg.py.
numpy, scipy, matplotlib, sewar (optional)
# Jupyter notebook recommended
# Use %load_ext autoreload
# and %autoreload 2
# in the Jupyter notebook to automatically
# refresh the imported modules on every run
import numpy as np
import matplotlib.pyplot as plt
from helpers import *
from helpers_jpeg import JpegHuff
jpeg = JpegHuff()
# Use functions before Section 10 of the handout directly
C8 = dct_ii(8)
Y = colxfm(colxfm(X, C8).T, C8).T
draw(beside(X1, X2, X3, X4)) # Improved beside(*args) function
plt.show() # Optional in Jupyter notebook
# Use the new functions in Section 12 of the handout
# in the JpegHuff class
vlc, _bits, _huffval = jpeg.jpegenc(X-128, qstep)
Z = jpeg.jpegdec(vlc, qstep)For more usage, refer to the project work in the jupyter notebooks in the separate repository.
The tests were written in pytest but only have minimum code coverage, so passing the tests does not mean the code base is bug free. Run pytest in SF2_Python/ to run the tests. The code of project work is tested as well.
This repository is provided with no warranty of any kind (MIT license).
The comments and doc strings were mostly copied from the old Matlab files and may not comply with good Python styles.