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SheatNoisette/char_detect.py

Last active October 31, 2019 17:07
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Naive characters detection in a 2D array
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char_detect.py
#!/usr/bin/env python
import os
# Find characters in a 2D array and return their position in the grid
# Basis for a simple optical recognition software
# MIT License
char_array = [
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,1,1,1,1,1,0,0,1,1,1,1,1,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,1,1,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,1,1,1,1,1,0,0,0,0,1,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
]
char_array_i = [
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0]
]
#Utils
#Count number of '1' in a list
def sum_line(list):
counter = 0
for element in list:
if element == 1:
counter += 1
return counter
#Count number '1' vertically in an array
def sum_vertical_array(array, x1, y1, y2):
counter = 0
currentY = y1
while currentY < y2:
if array[currentY][x1] == 1:
counter += 1
currentY += 1
return counter
# Output y: [1,6,9,14,16,21]
def find_char_y_pos(array):
yArray = len(array)
yPos = 0
detectY = []
lineRecognised = False
currentSum = 0
while yPos < yArray:
currentSum = sum_line(array[yPos])
if currentSum > 0 and not lineRecognised:
lineRecognised = True
detectY.append(yPos)
elif currentSum == 0 and lineRecognised:
detectY.append(yPos - 1)
lineRecognised = False
#If we are at the end of the array and the line isn't finished
elif yPos == yArray - 1 and lineRecognised:
detectY.append(yArray - 1)
yPos += 1
return detectY
def find_char_x_pos(array, yPosList):
if len(yPosList)%2 != 0:
print("Y List length error in find_char_xpos: ", str(yPosList))
return -1
xArray = len(array[0])
yPosLeft = len(yPosList) // 2
# Keep track of the position
currentYPos = 0
currentXPos = 0
# Current Horizontal sum
currentSum = 0
# Found a char?
charRecognised = False
# Current X char position
currentCharDetected = []
finalCharDetected = []
while yPosLeft > 0:
# Reset x cursor
currentXPos = 0
# Reset X Sum
currentSum = 0
#Reset current position detected
currentCharDetected = []
# Read horizontally
while currentXPos < xArray:
# Get vertical sum
currentSum = sum_vertical_array(array, currentXPos, yPosList[currentYPos], yPosList[currentYPos + 1])
if currentSum > 0 and not charRecognised:
# Beginning of the char
charRecognised = True
# Add X1 and Y1
currentCharDetected.append(currentXPos)
currentCharDetected.append(yPosList[currentYPos])
elif currentSum == 0 and charRecognised:
# End of the Char
charRecognised = False
# Add X2 and Y2
currentCharDetected.append(currentXPos - 1)
currentCharDetected.append(yPosList[currentYPos + 1])
# Add the char position to final list
finalCharDetected.append(currentCharDetected)
# Reset for the next char
currentCharDetected = []
currentXPos += 1
# Go to the next line
currentYPos += 2
# -1 Y couple remaining
yPosLeft -= 1
return finalCharDetected
def find_char_array(array):
return find_char_x_pos(array, find_char_y_pos(array))
# Output example: [Char 1: [x1, y1, x2, y2], ...]
print(find_char_array(char_array))
print(find_char_array(char_array_i))
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