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Wednesday, April 17, 2019

Update python modules of 3.73 version.

Today we tested an older tool with the new version of python 3.7.3.
This is a tool that will help you update your python modules.
Here's how to install:
C:\Python373\Scripts>pip install pip-review
Collecting pip-review
...
Requirement already satisfied: pyparsing>=2.0.2 in c:\python373\lib\site-package
s (from packaging->pip-review) (2.4.0)
Installing collected packages: packaging, pip-review
Successfully installed packaging-19.0 pip-review-1.0
Here is the complete overview of the options.
C:\Python373\Scripts>pip-review -h
usage: pip-review [-h] [--verbose] [--raw] [--interactive] [--auto]

Keeps your Python packages fresh.

optional arguments:
  -h, --help         show this help message and exit
  --verbose, -v      Show more output
  --raw, -r          Print raw lines (suitable for passing to pip install)
  --interactive, -i  Ask interactively to install updates
  --auto, -a         Automatically install every update found

Unrecognised arguments will be forwarded to pip list --outdated, so you can
pass things such as --user, --pre and --timeout and they will do exactly what
you expect. See pip list -h for a full overview of the options.
To update all python modules you can use:
C:\Python373\Scripts>pip-review --auto
To run interactively, you can ask to upgrade for each package:
C:\Python373\Scripts>pip-review --interactive


Monday, April 15, 2019

Using the ORB feature from OpenCV python module.

Today I will show you a simple script using the ORB (oriented BRIEF), see C++ documentation / OpenCV.
The algorithm uses FAST in pyramids to detect stable keypoints, selects the strongest features using FAST or Harris response, finds their orientation using first-order moments and computes the descriptors using BRIEF (where the coordinates of random point pairs (or k-tuples) are rotated according to the measured orientation).
One good feature of ORB is the is rotation invariant and resistant to noise.
The ORB descriptor use the Center of the mass of the patch of the Moment (sum of x,y), Centroid (the result of the matrix of all moment) and Orientation ( the atan2 of moment one and two).
One good article about ORB can be found here.
Let's see the script code of this python example:
import cv2
import numpy as np 

image_1 = cv2.imread("1.png", cv2.IMREAD_GRAYSCALE)
image_2 = cv2.imread("2.png", cv2.IMREAD_GRAYSCALE)

orb = cv2.ORB_create()
kp1, des1 = orb.detectAndCompute(image_1,None)
kp2, des2 = orb.detectAndCompute(image_2,None)

bf = cv2.BFMatcher(cv2.NORM_HAMMING, crossCheck=True)
matches = bf.match(des1, des2)
matches = sorted(matches, key = lambda x:x.distance)

matching_result = cv2.drawMatches(image_1, kp1, image_2, kp2, matches[:150], None, flags=2)

cv2.imshow("Image 1", image_1)
cv2.imshow("Image 2", image_2)
cv2.imshow("Matching result", matching_result)
cv2.waitKey(0)
cv2.destroyAllWindows()
The script use two file images 1.png and 2.png.
The result is an image composed of the two on which the areas of similitude are traced as detected by the mathematical algorithm.

Sunday, April 14, 2019

Using the python module music21.

What is music21?
Music21 is a set of tools for helping scholars and other active listeners answer questions about music quickly and simply. If you’ve ever asked yourself a question like, “I wonder how often Bach does that” or “I wish I knew which band was the first to use these chords in this order,” or “I’ll bet we’d know more about Renaissance counterpoint (or Indian ragas or post-tonal pitch structures or the form of minuets) if I could write a program to automatically write more of them,” then music21 can help you with your work.
This toolkit for Computer-Aided Musical Analysis was developed at MIT by cuthbertLab. Michael Scott Cuthbert, Principal Investigator.
The development of music21 is supported by the generosity of the Seaver Institute and the NEH.
The tutorial today is about the python music21 module.
Let's start with the default pip tool to install this python module:
C:\Python364\Scripts>pip install --upgrade music21
Collecting music21
...
  Running setup.py install for music21 ... done
Successfully installed music21-5.5.0
The next step tells us to install some additional python modules:
C:\Python373>python.exe
Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 22:22:05) [MSC v.1916 64 bit (AMD64)]
 on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from music21 import * 
music21: Certain music21 functions might need these optional packages: matplotlib,
 scipy;
if you run into errors, install them by following the instructions at
http://mit.edu/music21/doc/installing/installAdditional.html
Let's install these python modules:
C:\Python373\Scripts>pip install matplotlib
C:\Python373\Scripts>pip install scipy
Let's test and play a simple example (Bach’s BWV 66.6):
>>> from music21 import *
>>> s = corpus.parse('bwv66.6')
>>> sChords = s.chordify()
>>> sChords
...
>>> sChords.show('midi')
If you want to save it, use:
>>> sChords.write("midi", "bach6.mid")
'bach6.mid'
Another example is to play a note on guitar (C#):
from music21 import stream, instrument
from music21.note import Note
cd = Note("C#", type='quarter')
test = stream.Part()
test.insert(0, instrument.AcousticGuitar())
test_measure = stream.Measure()
test_measure.append(cd)
test.append(test_measure)
test.show('midi')
You can see all the instruments here.
This python module is very complex and can be used with additional software, see here.
More details can be found in the documentation.

Friday, April 12, 2019

Using pytineye to automate searching for images.

The TinEye API is ideally suited for image and profile verification, UGC moderation, copyright compliance and fraud detection.
Read more about the TinEye API here.
You need to use authentication for this API, read here.
To use the TinEye API you must purchase a search bundle.
The documentation for Python can be found here.
Let's start with the installation.
You need to download the zip file from GitHub and install using the pip tool:
C:\Python373\Scripts>pip3.7.exe install pytineye-master.zip
...
Successfully installed pytineye-1.3

>>> import pytineye
>>> from pytineye import TinEyeAPIRequest
>>> myapi = TinEyeAPIRequest('http://api.tineye.com/rest/', 'your_public_key', 'your_private_key')
>>> myapi.remaining_searches()
{'bundles': [], 'total_remaining_searches': 0}
Because I don't have search the python code return an error:
>>> myapi.search_url(url='http://en.es-static.us/upl/2019/03/rogue-planet-CFBD-S
IR-J214947.2-040308.9-2012-800x450.jpg')
Traceback (most recent call last):
  File "", line 1, in 
  File "C:\Python373\lib\site-packages\pytineye\api.py", line 304, in search_url

    obj = self._request('search', params, **kwargs)
  File "C:\Python373\lib\site-packages\pytineye\api.py", line 276, in _request
    raise TinEyeAPIError(obj['code'], obj.get('messages'))
pytineye.exceptions.TinEyeAPIError: APIError:
                   code    = 401
                   message = ['AUTHORIZATION_ERROR', 'You have no more searches
available. Please purchase another bundle if you wish to make more searches.']
If you want to buy TinEye API searches then the prices start from:
5,000 searches $200.00 USD($0.04 per search)
10,000 searches $300.00 USD($0.03 per search)
50,000 searches $1,000.00 USD($0.02 per search)
1,000,000 searches $10,000.00 USD($0.01 per search)

Friday, April 5, 2019

First test with 3.7.3 and opencv-python module version 4.0.0 .

The Python 3.7.3 is the third maintenance release of Python 3.7 and is released at March 25, 2019.
More about this new released version can be found at official website.
C:\Python373\Scripts>pip install opencv-python
Collecting opencv-python
...
Installing collected packages: numpy, opencv-python
Successfully installed numpy-1.16.2 opencv-python-4.0.0.21
Let's test it:
C:\Python373>python.exe
Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 22:22:05) [MSC v.1916 64 bit (AMD64)]
 on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import cv2
>>> cv2.__version__
'4.0.0'
Let test a simple example that computes a dense optical flow using the Gunnar Farneback’s algorithm.
import cv2
import numpy as np
cap = cv2.VideoCapture(0)
ret, frame1 = cap.read()
prvs = cv2.cvtColor(frame1,cv2.COLOR_BGR2GRAY)
hsv = np.zeros_like(frame1)
hsv[...,1] = 255
while(1):
    ret, frame2 = cap.read()
    next = cv2.cvtColor(frame2,cv2.COLOR_BGR2GRAY)
    flow = cv2.calcOpticalFlowFarneback(prvs,next, None, 0.1, 1, 2, 3, 5, 11.2, 0)
    mag, ang = cv2.cartToPolar(flow[...,0], flow[...,1])
    hsv[...,0] = ang*180/np.pi/2
    hsv[...,2] = cv2.normalize(mag,None,0,255,cv2.NORM_MINMAX)
    bgr = cv2.cvtColor(hsv,cv2.COLOR_HSV2BGR)
    cv2.imshow('frame2',bgr)
    k = cv2.waitKey(30) & 0xff
    if k == 27:
        break
    prvs = next
cap.release()
cv2.destroyAllWindows()

Wednesday, April 3, 2019

About Ninja IDE for python programming.

This I.D.E. is a very good tool for python programming and development.
The version of this tool is 2.3.
I tested with my Django project on Windows OS and works great.
The development team comes with this info:
NINJA-IDE (from the recursive acronym: "Ninja-IDE Is Not Just Another IDE"), is a cross-platform integrated development environment (IDE). NINJA-IDE runs on Linux/X11, Mac OS X and Windows desktop operating systems, and allows developers to create applications for several purposes using all the tools and utilities of NINJA-IDE, making the task of writing software easier and more enjoyable.
The official webpage can be found here.
If you want to use it with Django the easy way is to install the plugin for this area.
You can see all about the development team about page.