contour | 易学教程

Convolutional Networks for Image Semantic Segmentation

阅读更多关于 Convolutional Networks for Image Semantic Segmentation

感谢分享。http://yhlleo.github.io/2016/10/19/CNN-SemanticSeg/ 把前段时间自己整理的一个关于卷积神经网络应用于图像语义分割的PPT整理发布在本篇博客内，由于部分内容还在研究或发表过程中，就只上传PPT前两部分的内容。今天给大家介绍卷积神经网络在图像语义分割上的一些方法和应用。 PPT的目录包括，语义分割的简单介绍，然后介绍一些我的研究和具体的应用，最后简单说一下我最近的一些研究工作。图像语义，也就是图像理解，图像作为一种信息记录方式，每张图像都会传达出一些信息，就像一个故事。比如左边的图像，我们可以简单地分析出，有一只黑白斑纹的小猫，趴在一个木质的小木桌上，一只爪子按着一个有线鼠标，另一只放在一个打开的黑色的笔记本电脑上，旁边好像还站着个人。但是怎么能让计算机理解这些呢？这是个很难的问题，即便现在我们通过深度学习进行目标检测，可以得到图像场景中可能有哪些目标，但是要实现这样更深层次的理解，还是非常困难。目标检测和语义分割，是两种理解图像语义的基础方法，主要是为了解决，图像中有什么，在哪里的问题。虽然看起来解决的问题很相似，但是却差异很大。从输出结果来看，目标检测网络更加宽松，只要给定一个包含目标的最小窗口区域就可以，可以说它是window级别的方法，得到粗检测结果；而分割网络更加细致，强调像素级的精细化检测结果

Plotting contours on an irregular grid

阅读更多关于 Plotting contours on an irregular grid

问题 I have gone through pages and pages of contour plots in R (including many hints on stackoverflow) without success. Here is my data to contour, including adding a map of Rwanda (the data consists of 14 values of longitude, latitude and rain as x,y and z): Lon Lat Rain 28.92 -2.47 83.4 29.02 -2.68 144 29.25 -1.67 134.7 29.42 -2.07 174.9 29.55 -1.58 151.5 29.57 -2.48 224.1 29.6 -1.5 254.3 29.72 -2.18 173.9 30.03 -1.95 154.8 30.05 -1.6 152.2 30.13 -1.97 126.2 30.33 -1.3 98.5 30.45 -1.81 145.5 30

Find edge of black and white image

阅读更多关于 Find edge of black and white image

问题 I need to find the edge and generate points of a black and white image like the one below: I am not sure how to go about doing this. I know OpenCV is an option, but that is way overkill for what is sure to be a simple task. Does anyone know any easy way to do this? Libraries are okay, as long as they aren't too heavyweight (header only preferred) 回答1: I would use a Canny Edge Detection, though you can easily experiment with the others that @therainmaker suggests. I would use ImageMagick which

基于三维GIS技术的公路交通数字孪生系统

阅读更多关于基于三维GIS技术的公路交通数字孪生系统

3 月，跳不动了？>>> 交通运输系统是四个现代化建设的重要保障，在“一带一路”倡议规划背景下，互联网+、智慧交通提升到国家新战略。智慧交通的基石是建立可映射物理世界的虚拟世界，因此大多数交通管理平台项目通过抽象建模构造二维电子地图，并在抽象模型上集成数据及分析工具，实现运营期信息化管理。随着设计、施工、运营全生命周期细化管理日益增长的需求，传统的交通地理信息(Geographic Informa-tion System-Transportation,GIS-T)系统的压力也随之增加。交通基础设施数字化映射为三维GIS 信息世界的技术方案是突破二维GIS-T系统局限的有效途径，其已成为交通信息化研究的热点课题，目前研究主要集中于建模、数据库协同、可视化分析。（1）在建模方面，通过三维GIS平台场景中集成建筑信息模型(Building Information Modeling, BIM)软件创建的地物模型达到宏观和微观的信息表达是最直观的思路。实践发现，交通以线状工程为主，其结构复杂性远低于建筑工程，照搬建筑业BIM不可复用的手工建模方式具有高人力投人的特点，缺乏项目各生命周期出现的模型、选线变更高效应对手段。点云、倾斜摄影等基于机载激光雷达的标准数据(LIDAR Standard, LAS)雷达和图形学的建模方法十分先进但只适用于运营期，且模型单体化处理技术尚不成熟

Extract area detected by color using OpenCV in Android

阅读更多关于 Extract area detected by color using OpenCV in Android

问题 The sample project named "color-blob-detection" that comes with the openCV SDK for android can be used to identify an area of a particular color. What I require is to extract that area and save it into the phone memory as a bitmap. This is what I have understood so far: There is a list of contours: List<MatOfPoint> contours = new ArrayList<MatOfPoint>(); Contours are found using: Imgproc.findContours(mDilatedMask, contours, mHierarchy, Imgproc.RETR_EXTERNAL, Imgproc.CHAIN_APPROX_SIMPLE); This

matplotlib: preventing a few very large (or small) values to affect my contour

阅读更多关于 matplotlib: preventing a few very large (or small) values to affect my contour

问题 in plotting the data some times there are a few very large (or very small) numbers which, if not taken care of, will affect the contour in a bad way. a solution is to take out the 10% highest and lowest data out of the contour color grading and considering them as less than and more than. the following figure shows the idea: the two arrow shapes on the top and the bottom of the bar support this idea. any value above 14 will be shown in white and any value below -2 will be shown in black color

Finding Largest Contours C++

阅读更多关于 Finding Largest Contours C++

问题 I am currently trying to create a program that finds the edges of a receipt and then crops it accordingly. I used this code to do so: vector<vector<cv::Point> > contours; vector<Vec4i> hierarchy; findContours(edged, contours, hierarchy, CV_RETR_LIST, CV_CHAIN_APPROX_NONE); sort(contours.begin(), contours.end(), compareContourAreas); vector<cv::Point> target; for(int i = 0; i < contours.size(); i++){ vector<cv::Point> c = contours[i]; double p = arcLength(c, true); vector<cv::Point> approx;

segmentation fault in findcontours opencv

阅读更多关于 segmentation fault in findcontours opencv

问题 I am trying to detect a ball and draw boundaries to it. It shows the error segmentation fault (core dumped) The mistake is somewhere here, vector<vector<Point> > contours; vector<Vec4i> hierarchy; Mat itt = Mat::zeros( imgThresholded.size(), CV_8UC1 ); itt = imgThresholded*255; Canny( itt ,itt, 10, 30, 3 ); vector<vector<Point> > contours_poly( contours.size() ); vector<Point2f>center( contours.size() ); vector<float>radius( contours.size() ); vector<Rect> boundRect( contours.size() ); imshow

How to warp a rectangular object to fit its larger bounding box

阅读更多关于 How to warp a rectangular object to fit its larger bounding box

问题 Given this image: I'd like to make it such that it will rotate and stretch to fully fit in the bounding box with no whitespace on the outside of the largest rectangular box. It should also account for worse perspective case, like in the links I list later on. Basically, while it is not noticeable, the rectangle is rotated a little bit, and I'd like to fix that distortion. However, I got an error when attempting to retrieve the four points of the contour. I have made sure and utilized contour

How to warp a rectangular object to fit its larger bounding box

阅读更多关于 How to warp a rectangular object to fit its larger bounding box

订阅 contour