viola-jones

Number of haar like features in 24x24 window

≯℡__Kan透↙ 提交于 2020-03-20 04:54:35
问题 Referring to the following link Viola & Jones Face Detection The above link contains the calculation regarding the number of haar features corresponding to different templates(below is excerpt from the link). I am not getting how those(43200,27600,43200,27600,20736) exact calculations are made.Can somebody explain that to me in an easy way? 回答1: To understand, have a look at the algorithm #1. For the first pattern (a) , the following two lines (5 and 6 in the article) gives the explanations

Number of haar like features in 24x24 window

心已入冬 提交于 2020-03-20 04:54:04
问题 Referring to the following link Viola & Jones Face Detection The above link contains the calculation regarding the number of haar features corresponding to different templates(below is excerpt from the link). I am not getting how those(43200,27600,43200,27600,20736) exact calculations are made.Can somebody explain that to me in an easy way? 回答1: To understand, have a look at the algorithm #1. For the first pattern (a) , the following two lines (5 and 6 in the article) gives the explanations

Number of haar like features in 24x24 window

和自甴很熟 提交于 2020-03-20 04:49:36
问题 Referring to the following link Viola & Jones Face Detection The above link contains the calculation regarding the number of haar features corresponding to different templates(below is excerpt from the link). I am not getting how those(43200,27600,43200,27600,20736) exact calculations are made.Can somebody explain that to me in an easy way? 回答1: To understand, have a look at the algorithm #1. For the first pattern (a) , the following two lines (5 and 6 in the article) gives the explanations

Threshold values for viola jones object detection

北战南征 提交于 2020-01-03 05:01:08
问题 I am trying to perform Adaboost training stated by Viola and Jones in their paper on rapid object detection. However, I do not understand how to get the threshold values that will classify the faces from non faces for each of the 160k features. Is this a threshold you set manually? or is this based on some kind of maths ? Can someone please explain the maths to me thanks a lot. 回答1: IMO, the best way to describe what happens during threshold assignment of the weak classifiers in every

Haar Cascades vs. LBP Cascades in Face Detection

和自甴很熟 提交于 2019-12-20 08:00:33
问题 I have been experimenting with face detection in OpenCV (Open Source Computer Vision Library), and found that one could use Haar cascades to detect faces as there are several of them provided with OpenCV. However, I have noticed that there are also several LBP cascades. After doing some research, I found that LBP stands for Local Binary Patterns, and it can also be used for face detection, according to the OpenCV Face Detection Documentation. What I would like to know is, which works better?

Do I have to train Viola-Jones Algorithm with my database to obtain accurate results?

泪湿孤枕 提交于 2019-12-07 09:07:30
问题 I try to extract facial features of a face database but I recognized that Viola-Jones algorithm is not working well* in two cases: When I try to detect the eyes singly, When I try to detect the mouth. * Not working well : Detects different parts of the image as eyes or mouth. Or sometimes detects several of them which is an impossible case. The images I'm using have pure green background and contains a person's frontal face. Detection.cpp: #include "Detection.h" Detection::Detection(const

Face Detection Algorithms with minimal training time [closed]

对着背影说爱祢 提交于 2019-11-30 04:08:24
Wanted to ask if there was any kind of face detection scheme suitable for video that would require minimal training time ideally about a few days rather than weeks like the Viola-Jones. I have read about LBP but it requires a huge set of training samples too but not sure how long it takes. Does training an LBP consume as much time as the Viola - Jones method with a similar number of training set ?. I will be implementing this on a microprocessor like raspberry pi running on a linux OS. Will want to implement it on C for speed as I want it to be able to detect images in a 10fps - 20fps video

Face Detection Algorithms with minimal training time [closed]

不想你离开。 提交于 2019-11-29 02:02:51
问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 6 years ago . Wanted to ask if there was any kind of face detection scheme suitable for video that would require minimal training time ideally about a few days rather than weeks like the Viola-Jones. I have read about LBP but it requires a huge set of training samples too but not sure how long

How does the Viola-Jones face detection method work?

不羁岁月 提交于 2019-11-28 15:32:46
Please explain to me, in few words, how the Viola-Jones face detection method works. cMinor The Viola-Jones detector is a strong, binary classifier build of several weak detectors Each weak detector is an extremely simple binary classifier During the learning stage, a cascade of weak detectors is trained so as to gain the desired hit rate / miss rate (or precision / recall) using Adaboost To detect objects, the original image is partitioned in several rectangular patches, each of which is submitted to the cascade If a rectangular image patch passes through all of the cascade stages, then it is

Viola-Jones' face detection claims 180k features

我们两清 提交于 2019-11-28 02:39:46
I've been implementing an adaptation of Viola-Jones' face detection algorithm . The technique relies upon placing a subframe of 24x24 pixels within an image, and subsequently placing rectangular features inside it in every position with every size possible. These features can consist of two, three or four rectangles. The following example is presented. They claim the exhaustive set is more than 180k (section 2): Given that the base resolution of the detector is 24x24, the exhaustive set of rectangle features is quite large, over 180,000 . Note that unlike the Haar basis, the set of rectangle