MareArts Computer Vision Study.: 2019.08

8/24/2019

python string encryption, decryption - example code

from cryptography.fernet import Fernet

def encrypt(message: bytes, key: bytes):
    return Fernet(key).encrypt(message)

def decrypt(token: bytes, key: bytes):
    return Fernet(key).decrypt(token)

key = Fernet.generate_key()  # store in a secure location
#ex) key is 'Fn1dPza4Gchl7KpPE4kz2oJEMFXYG39ykpSLcsT1icU='

message = 'This is scret string'
#encryption
enstr = encrypt(message.encode(), key)
#decryption
destr = decrypt(enstr, key).decode()

print('input:',  message)
print('encryption:', enstr)
print('decryption:', destr)

8/21/2019

get similarity between two graphs

Basically, this example use networkX python library.
I made very simple two graphs which are G1, G2

Let see here:

and nx.graph_edit_distance this function calculate how much edit graph can be became isomorphic, that is return value of the function.

Check the example code.

..

#https://stackoverflow.com/questions/11804730/networkx-add-node-with-specific-position
#https://stackoverflow.com/questions/23975773/how-to-compare-directed-graphs-in-networkx

import matplotlib.pyplot as plt
import networkx as nx
G1=nx.Graph()
G1.add_node(1,pos=(1,1))
G1.add_node(2,pos=(2,2))
G1.add_node(3,pos=(3,1))
G1.add_edge(1,2)
G1.add_edge(1,3)

pos=nx.get_node_attributes(G1,'pos')
plt.figure('graph1')
nx.draw(G1,pos, with_labels=True)

G2=nx.Graph()
G2.add_node(1,pos=(10,10))
G2.add_node(2,pos=(20,20))
G2.add_node(3,pos=(30,10))
G2.add_node(4,pos=(40,30))
G2.add_edge(1,2)
G2.add_edge(1,3)
G2.add_edge(1,4)
pos2=nx.get_node_attributes(G2,'pos')
plt.figure('b')
nx.draw(G2,pos2, with_labels=True)

dist = nx.graph_edit_distance(G1, G2)
print(dist)

plt.show()

8/20/2019

compare text using fuzzy wuzzy in python

just refer to this example..it's simple and very useful.

#pip install fuzzywuzzy
from fuzzywuzzy import process
candidate = ["Atlanta Falcons", "New York Jetss", "New York Giants", "Dallas Cowboys"]
search = "new york jets"
r1 = process.extract(search, candidate) 
#r1 = process.extract(search, candidate, limit=3)
search = "cowboys"
r2 = process.extractOne(search, candidate)
search = "new york jets"
r3 = process.extractBests(search, candidate, score_cutoff=70)
print(r1)
#[('New York Jetss', 96), ('New York Giants', 79), ('Atlanta Falcons', 29), ('Dallas Cowboys', 22)]
print(r2)
#('Dallas Cowboys', 90)
print(r3)
#[('Dallas Cowboys', 90)]

8/08/2019

PIL to string, string to PIL (python)

It's simple example source code for that:

PIL to string(base64)
- PIL open image
- image to byte
- byte to string (base64)

string(base64) to PIL
- string to byte
- PIL load byte

--

import base64
import io
from PIL import Image

#open file using PIL
pil_img = Image.open('IMG_0510.jpg')
width, height = pil_img.size
print(width, height)


#get image data as byte
buffer = io.BytesIO()
pil_img.save(buffer, format=pil_img.format)
buffer_value = buffer.getvalue()

#byte to string
base64_str = base64.b64encode(buffer_value)

#read string to image buffer
buffer2 = base64.b64decode(base64_str)
pil_img2 = Image.open(io.BytesIO(buffer2))
width2, height2 = pil_img2.size
print(width2, height2)


#check first & second image
pil_img.show()
pil_img2.show()