Real-time stacked-up coin counts with the help of Computer Vision using Python-based OpenCV.

Hi Guys,

Today, I’ll be using another exciting installment of Computer Vision. Today, our focus will be to get a sense of visual counting. Let me explain. This post will demonstrate how to count the number of stacked-up coins using computer vision. And, we’re going to add more coins to see the number changes.

Why don’t we see the demo first before jumping into the technical details?

Demo

Isn’t it exciting?


Architecture:

Let us understand the architecture –

From the above diagram, one can notice that as raw video feed captured from a specific location at a measured distance. The python-based intelligent application will read the numbers & project on top of the video feed for human validations.

Let me share one more perspective of how you can configure this experiment with another diagram that I prepared for this post.

Setup Process

From the above picture, one can see that a specific distance exists between the camera & the stacked coins as that will influence the single coin width.

You can see how that changed with the following pictures –

This entire test will depend upon many factors to consider to get effective results. I provided the basic demo. However, to make it robust & dynamic, one can dynamically diagnose the distance & individual coin width before starting this project. I felt that part should be machine learning to correctly predict the particular coin width depending upon the length & number of coins stacked. I leave it to you to explore that part.

Then how does the Aruco marker comes into the picture?

Let’s read it from the primary source side –

From: Source

Please refer to the following link if you want to know more.

For our use case, we’ll be using the following aruco marker –

Marker

How will this help us? Because we know the width & height of it. And depending upon the placement & overall pixel area size, our application can then identify the pixel to centimeter ratio & which will enable us to predict any other objects’ height & width. Once we have that, the application will divide that by the calculated width we observed for each coin from this distance. And, then the application will be able to predict the actual counts in real-time.

How can you identify the individual width?

My easy process would be to put ten quarter dollars stacked up & then you will get the height from the Computer vision. You have to divide that height by 10 to get the individual width of the coin until you build the model to predict the correct width depending upon the distance.


CODE:

Let us understand the code now –

  • clsConfig.py (Configuration file for the entire application.)


################################################
#### Written By: SATYAKI DE ####
#### Written On: 15-May-2020 ####
#### Modified On: 28-Dec-2021 ####
#### ####
#### Objective: This script is a config ####
#### file, contains all the keys for ####
#### Machine-Learning & streaming dashboard.####
#### ####
################################################
import os
import platform as pl
class clsConfig(object):
Curr_Path = os.path.dirname(os.path.realpath(__file__))
os_det = pl.system()
if os_det == "Windows":
sep = '\\'
else:
sep = '/'
conf = {
'APP_ID': 1,
'ARCH_DIR': Curr_Path + sep + 'arch' + sep,
'PROFILE_PATH': Curr_Path + sep + 'profile' + sep,
'LOG_PATH': Curr_Path + sep + 'log' + sep,
'REPORT_PATH': Curr_Path + sep + 'report',
'FILE_NAME': Curr_Path + sep + 'Image' + sep + 'Orig.jpeg',
'SRC_PATH': Curr_Path + sep + 'data' + sep,
'APP_DESC_1': 'Old Video Enhancement!',
'DEBUG_IND': 'N',
'INIT_PATH': Curr_Path,
'SUBDIR': 'data',
'SEP': sep,
'COIN_DEF_HEIGHT':0.22,
'PIC_TO_CM_MAP': 15.24,
'CONTOUR_AREA': 2000
}

view raw

clsConfig.py

hosted with ❤ by GitHub

'COIN_DEF_HEIGHT':0.22,
'PIC_TO_CM_MAP': 15.24,
'CONTOUR_AREA': 2000

The above entries are the important for us.

  1. PIC_TO_CM_MAP is the total length of the Aruco marker in centimeters involving all four sides.
  2. CONTOUR_AREA will change depending upon the minimum size you want to identify as part of the contour.
  3. COIN_DEF_HEIGHT needs to be revised as part of the previous steps explained.
  • clsAutoDetector.py (This python script will detect the contour.)


###############################################
#### Written By: SATYAKI DE ####
#### Written On: 17-Jan-2022 ####
#### Modified On 20-Mar-2022 ####
#### ####
#### Objective: This python script will ####
#### auto-detects the contours of an image ####
#### using grayscale conversion & then ####
#### share the contours details to the ####
#### calling class. ####
###############################################
import cv2
from clsConfig import clsConfig as cf
class clsAutoDetector():
def __init__(self):
self.cntArea = int(cf.conf['CONTOUR_AREA'])
def detectObjects(self, frame):
try:
cntArea = self.cntArea
# Convert Image to grayscale Image
grayImage = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
# Create a Mask with adaptive threshold
maskImage = cv2.adaptiveThreshold(grayImage, 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY_INV, 19, 5)
cv2.imshow("Masked-Image", maskImage)
# Find contours
conts, Oth = cv2.findContours(maskImage, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
objectsConts = []
for cnt in conts:
area = cv2.contourArea(cnt)
if area > cntArea:
objectsConts.append(cnt)
return objectsConts
except Exception as e:
x = str(e)
print('Error: ', x)
objectsConts = []
return objectsConts

Key snippets from the above script are as follows –

# Find contours
conts, Oth = cv2.findContours(maskImage, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)

objectsConts = []

for cnt in conts:
    area = cv2.contourArea(cnt)
    if area > cntArea:
        objectsConts.append(cnt)

Depending upon the supplied contour area, this script will identify & mark the contour of every frame captured through WebCam.

  • clsCountRealtime.py (This is the main class to calculate the number of stacked coins after reading using computer vision.)


##################################################
#### Written By: SATYAKI DE ####
#### Written On: 17-Jan-2022 ####
#### Modified On 20-Mar-2022 ####
#### ####
#### Objective: This python class will ####
#### learn the number of coins stacks on ####
#### top of another using computer vision ####
#### with the help from Open-CV after ####
#### manually recalibarting the initial ####
#### data (Individual Coin Heights needs to ####
#### adjust based on the distance of camera.) ####
##################################################
import cv2
from clsAutoDetector import *
import numpy as np
import os
import platform as pl
# Custom Class
from clsConfig import clsConfig as cf
import clsL as cl
# Initiating Log class
l = cl.clsL()
# Load Aruco detector
arucoParams = cv2.aruco.DetectorParameters_create()
arucoDict = cv2.aruco.Dictionary_get(cv2.aruco.DICT_5X5_50)
# Load Object Detector
detector = clsAutoDetector()
class clsCountRealtime:
def __init__(self):
self.sep = str(cf.conf['SEP'])
self.Curr_Path = str(cf.conf['INIT_PATH'])
self.coinDefH = float(cf.conf['COIN_DEF_HEIGHT'])
self.pics2cm = float(cf.conf['PIC_TO_CM_MAP'])
def learnStats(self, debugInd, var):
try:
# Per Coin Default Size from the known distance_to_camera
coinDefH = self.coinDefH
pics2cm = self.pics2cm
# Load Cap
cap = cv2.VideoCapture(0)
cap.set(cv2.CAP_PROP_FRAME_WIDTH, 1280)
cap.set(cv2.CAP_PROP_FRAME_HEIGHT, 720)
while True:
success, img = cap.read()
if success == False:
break
# Get Aruco marker
imgCorners, a, b = cv2.aruco.detectMarkers(img, arucoDict, parameters=arucoParams)
if imgCorners:
# Draw polygon around the marker
imgCornersInt = np.int0(imgCorners)
cv2.polylines(img, imgCornersInt, True, (0, 255, 0), 5)
# Aruco Perimeter
arucoPerimeter = cv2.arcLength(imgCornersInt[0], True)
# Pixel to cm ratio
pixelCMRatio = arucoPerimeter / pics2cm
contours = detector.detectObjects(img)
# Draw objects boundaries
for cnt in contours:
# Get rect
rect = cv2.boundingRect(cnt)
(x, y, w, h) = rect
print('*'*60)
print('Width Pixel: ')
print(str(w))
print('Height Pixel: ')
print(str(h))
# Get Width and Height of the Objects by applying the Ratio pixel to cm
objWidth = round(w / pixelCMRatio, 1)
objHeight = round(h / pixelCMRatio, 1)
cv2.rectangle(img, (x, y), (x + w, y + h), (255, 0, 0), 2)
cv2.putText(img, "Width {} cm".format(objWidth), (int(x – 100), int(y – 20)), cv2.FONT_HERSHEY_PLAIN, 2, (100, 200, 0), 2)
cv2.putText(img, "Height {} cm".format(objHeight), (int(x – 100), int(y + 15)), cv2.FONT_HERSHEY_PLAIN, 2, (100, 200, 0), 2)
NoOfCoins = round(objHeight / coinDefH)
cv2.putText(img, "No Of Coins: {}".format(NoOfCoins), (int(x – 100), int(y + 35)), cv2.FONT_HERSHEY_PLAIN, 2, (250, 0, 250), 2)
print('Final Height: ')
print(str(objHeight))
print('No Of Coins: ')
print(str(NoOfCoins))
cv2.imshow("Image", img)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
cap.release()
cv2.destroyAllWindows()
return 0
except Exception as e:
x = str(e)
print('Error: ', x)
return 1

Some of the key snippets from this script –

# Aruco Perimeter
arucoPerimeter = cv2.arcLength(imgCornersInt[0], True)

# Pixel to cm ratio
pixelCMRatio = arucoPerimeter / pics2cm

The above lines will extract the critical auroco perimeter & then the ratio between pixel against centimeters.

contours = detector.detectObjects(img)

The application detects the contours of each frame from the previous class, which will be used here.

# Draw objects boundaries
for cnt in contours:
    # Get rect
    rect = cv2.boundingRect(cnt)
    (x, y, w, h) = rect

In this step, the application will draw the object contours & also capture the center points, along with the height & width of the identified objects.

# Get Width and Height of the Objects by applying the Ratio pixel to cm
objWidth = round(w / pixelCMRatio, 1)
objHeight = round(h / pixelCMRatio, 1)

Finally, identify the width & height of the contoured object in centimeters.

cv2.putText(img, "Width {} cm".format(objWidth), (int(x - 100), int(y - 20)), cv2.FONT_HERSHEY_PLAIN, 2, (100, 200, 0), 2)
cv2.putText(img, "Height {} cm".format(objHeight), (int(x - 100), int(y + 15)), cv2.FONT_HERSHEY_PLAIN, 2, (100, 200, 0), 2)

NoOfCoins = round(objHeight / coinDefH)

cv2.putText(img, "No Of Coins: {}".format(NoOfCoins), (int(x - 100), int(y + 35)), cv2.FONT_HERSHEY_PLAIN, 2, (250, 0, 250), 2)

It displays both the height, width & total number of coins on top of the live video.

if cv2.waitKey(1) & 0xFF == ord('q'):
    break

The above line will help the developer exit from the visual application by pressing the escape or ‘q’ key in Macbook.

  • visualDataRead.py (Main calling function.)


###############################################
#### Written By: SATYAKI DE ####
#### Written On: 17-Jan-2022 ####
#### Modified On 20-Mar-2022 ####
#### ####
#### Objective: This is the main calling ####
#### python script that will invoke the ####
#### clsCountRealtime class to initiate ####
#### the model to read the real-time ####
#### stckaed-up coins & share the actual ####
#### numbers on top of the video feed. ####
###############################################
# We keep the setup code in a different class as shown below.
import clsCountRealtime as ar
from clsConfig import clsConfig as cf
import datetime
import logging
###############################################
### Global Section ###
###############################################
# Instantiating all the three classes
x1 = ar.clsCountRealtime()
###############################################
### End of Global Section ###
###############################################
def main():
try:
# Other useful variables
debugInd = 'Y'
var = datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
var1 = datetime.datetime.now()
print('Start Time: ', str(var))
# End of useful variables
# Initiating Log Class
general_log_path = str(cf.conf['LOG_PATH'])
# Enabling Logging Info
logging.basicConfig(filename=general_log_path + 'restoreVideo.log', level=logging.INFO)
print('Started Capturing Real-Time Coin Counts!')
# Execute all the pass
r1 = x1.learnStats(debugInd, var)
if (r1 == 0):
print('Successfully counts number of stcaked coins!')
else:
print('Failed to counts number of stcaked coins!')
var2 = datetime.datetime.now()
c = var2 var1
minutes = c.total_seconds() / 60
print('Total difference in minutes: ', str(minutes))
print('End Time: ', str(var1))
except Exception as e:
x = str(e)
print('Error: ', x)
if __name__ == "__main__":
main()

And, the key snippet from the above script –

x1 = ar.clsCountRealtime()

The application instantiates the main class.

# Execute all the pass
r1 = x1.learnStats(debugInd, var)

if (r1 == 0):
    print('Successfully counts number of stcaked coins!')
else:
    print('Failed to counts number of stcaked coins!')

The above code invokes the learnStats function to calculate the count of stacked coins.


FOLDER STRUCTURE:

Folder Details

So, we’ve done it.

You will get the complete codebase in the following Github link.

I’ll bring some more exciting topic in the coming days from the Python verse. Please share & subscribe my post & let me know your feedback.

Till then, Happy Avenging! 😀

Note: All the data & scenario posted here are representational data & scenarios & available over the internet & for educational purpose only. Some of the images (except my photo) that we’ve used are available over the net. We don’t claim the ownership of these images. There is an always room for improvement & especially the prediction quality.

Oracle SQL & PL/SQL Basics.

Hi!

Friends, this page mainly deals with the basic of oracle sql & pl/sql. Here, i’m going to present many useful Oracle snippets which can be plugged into your solution. Many of the snippets which are going to be part of this blog are conceptualize and coded by me and many cases i got the idea from our brilliant otn members. I’m sure you people will like all the snippets as useful bricks. Very soon i am going to post many oracle sql & pl/sql .

Here i’m posting some useful SQL snippets which can be plugged into your environment –

SQL:

1. Dynamic Table Alteration:

Here is the sample code that demonstrate this –

scott>select * from v$version;
BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - Prod
PL/SQL Release 10.2.0.3.0 - Production
CORE 10.2.0.3.0 Production
TNS for 32-bit Windows: Version 10.2.0.3.0 - Production
NLSRTL Version 10.2.0.3.0 - Production

Elapsed: 00:00:00.09

scott>
scott>create table test_dummy
2 (
3 a varchar2(10)
4 );

Table created.

Elapsed: 00:00:05.00
scott>
scott>
scott>alter table &tab add (& col varchar2 ( 10 ));
Enter value for tab: test_dummy
Enter value for col: b
old 1: alter table &tab add (& col varchar2 ( 10 ))
new 1: alter table test_dummy add (b varchar2 ( 10 ))

Table altered.

Elapsed: 00:00:01.19

scott>
scott>desc test_dummy;
Name Null? Type
-------------------- -------- --------------
A VARCHAR2(10)
B VARCHAR2(10)


2. Alternative Of Break Command:

scott>
scott>SELECT lag(null, 1, d.dname)
over (partition by e.deptno order by e.ename) as dname,
2 e.ename
3 from emp e, dept d
4 where e.deptno = d.deptno
5 ORDER BY D.dname, e.ename;

DNAME ENAME
-------------- ----------
ACCOUNTING CLARK
KING
MILLER
RESEARCH ADAMS
FORD
JONES
SCOTT
SMITH
SALES ALLEN
BLAKE
JAMES

DNAME ENAME
-------------- ----------
MARTIN
TURNER
WARD

14 rows selected.

Elapsed: 00:00:00.52
scott>



3. Can we increase the size of a column for a View:

SQL> create or replace view v_emp
2 as
3 select ename
4 from emp
5 /
View created.

SQL> desc v_emp
Name Null? Type
----------------------------------------- -------- ----------------------------
ENAME VARCHAR2(10)
SQL>
SQL> create or replace view v_emp
2 as
3 select cast (ename as varchar2 (30)) ename
4 from emp
5 /
View created.

SQL> desc v_emp
Name Null? Type
----------------------------------------- -------- ----------------------------
ENAME VARCHAR2(30)

And here is the silly way to do this –

create or replace view temp_vv
as
select replace(ename,' ') ename
from (
select rpad(ename,100) ename
from emp
);

4. Combining two SQL Into One:

satyaki>
satyaki>select e.empno,e.deptno,d.loc "DEPT_10"
2 from emp e, dept d
3 where e.deptno = d.deptno
4 and d.deptno = 10;

EMPNO DEPTNO DEPT_10
---------- ---------- -------------
7782 10 NEW YORK
7839 10 NEW YORK
7934 10 NEW YORK

Elapsed: 00:00:00.04
satyaki>
satyaki>select e.empno,e.deptno,d.loc "DEPT_OTH"
2 from emp e, dept d
3 where e.deptno = d.deptno
4 and e.deptno not in (10);

EMPNO DEPTNO DEPT_OTH
---------- ---------- -------------
7369 20 DALLAS
7876 20 DALLAS
7566 20 DALLAS
7788 20 DALLAS
7902 20 DALLAS
7900 30 CHICAGO
7844 30 CHICAGO
7654 30 CHICAGO
7521 30 CHICAGO
7499 30 CHICAGO
7698 30 CHICAGO

11 rows selected.

Elapsed: 00:00:00.04
satyaki>
satyaki>
satyaki>select a.empno,(
2 select d.loc
3 from emp e, dept d
4 where e.deptno = d.deptno
5 and e.empno = a.empno
6 and d.deptno = 10
7 ) "DEPT_10" ,
8 (
9 select d.loc
10 from emp e, dept d
11 where e.deptno = d.deptno
12 and e.empno = a.empno
13 and d.deptno not in (10)
14 ) "DEPT_OTH"
15 from emp a
16 order by a.empno;

EMPNO DEPT_10 DEPT_OTH
---------- ------------- -------------
7369 DALLAS
7499 CHICAGO
7521 CHICAGO
7566 DALLAS
7654 CHICAGO
7698 CHICAGO
7782 NEW YORK
7788 DALLAS
7839 NEW YORK
7844 CHICAGO
7876 DALLAS

EMPNO DEPT_10 DEPT_OTH
---------- ------------- -------------
7900 CHICAGO
7902 DALLAS
7934 NEW YORK

14 rows selected.

Elapsed: 00:00:00.30
satyaki>

Regards.

Satyaki De.