The multivariate_normal component in the scipy stats library is a very useful component for many machine learning applications. I faced an issue while trying to import this library in my Jupyter notebook and I wanted to share how I fixed it. I am running python 2.7 on an Ubuntu 14.04 machine.
Showing posts with label Machine Learning. Show all posts
Showing posts with label Machine Learning. Show all posts
Thursday, March 30, 2017
Saturday, October 27, 2012
EXCEPTION_ACCESS_VIOLATION while using JavaCV Facerecognizer class
The below error while executing JavaCV code happen mostly when you try to invoke a method on a non-existing pointer.
#
# A fatal error has been detected by the Java Runtime Environment:
#
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x000007feea1adf5f, pid=10548, tid=8644
#
# JRE version: 7.0_07-b11
# Java VM: Java HotSpot(TM) 64-Bit Server VM (23.3-b01 mixed mode windows-amd64 compressed oops)
# Problematic frame:
# C [jniopencv_contrib.dll+0xdf5f]
#
We need to understand that JavaCV is a JNI wrapper for OpenCV and other similar native libraries. The objects returned using these methods work a bit different from the normal java objects. The above error happens mainly due to trying to operate on a pointer that no longer exists.
Please refer to the below class, for example
Creating an LBPH (Local Binary Pattern Histogram) face recognizer using FaceRecognizer class in JavaCV
In this article we will discuss how to create a Java based LBP face recognizer using JavaCV. JavaCV is a wrapper to the Open CV libraries for image processing. The workflow that I am trying to implement is as below
- The calling program will supply a bunch of images and a person name to this class ( learnNewFace(String personName, IplImage[] images)
- The class will store the images in a folder and map the person name to an integer id
- The class will then read all the images and person names and train the model
- Once training is complete client can invoke identifyFace method giving an image to find out the matching personName (identifyFace(IplImage image))