【issue-halcon例程学习】edges_color.hdev

例程功能

演示如何使用edges_color,展示只能从彩色图像中提取某些边缘的图像,说明edges_coloredges_image输出之间的差异。

代码如下

cpp 复制代码
dev_update_off ()
read_image (Image, 'olympic_stadium')
get_image_size (Image, Width, Height)
dev_close_window ()
dev_open_window (0, 0, Width, Height, 'black', WindowHandle)
dev_set_part (0, 0, Height - 1, Width - 1)
set_display_font (WindowHandle, 16, 'mono', 'true', 'false')
dev_display (Image)
Message := 'Color image'
disp_message (WindowHandle, Message, 'window', 12, 12, 'black', 'true')
stop ()
* Convert the color image to a gray value image.  Note that there is no contrast
* between the soccer field and the track in the gray value image.
rgb1_to_gray (Image, GrayImage)
dev_display (GrayImage)
Message := 'Gray value image'
disp_message (WindowHandle, Message, 'window', 12, 12, 'black', 'true')
stop ()
* Compute the color edges without non-maximum suppression and hysteresis
* thresholding, i.e., the raw edge amplitude image.  Note that there is a clearly
* visible edge between the soccer field and the track in the color edge image.
edges_color (Image, ImaAmp, ImaDir, 'canny', 1, 'none', -1, -1)
dev_display (ImaAmp)
Message := 'Color edge image'
disp_message (WindowHandle, Message, 'window', 12, 12, 'black', 'true')
stop ()
* Compute the gray value edges without non-maximum suppression and
* hysteresis thresholding, i.e., the raw edge amplitude image.  Note that there is
* no visible edge between the soccer field and the track in the gray value edge
* image.
edges_image (GrayImage, ImaAmpGray, ImaDirGray, 'canny', 1, 'none', -1, -1)
dev_display (ImaAmpGray)
Message := 'Gray value edge image'
disp_message (WindowHandle, Message, 'window', 12, 12, 'black', 'true')
stop ()
* Now perform the color edge extraction including non-maximum suppression
* and hysteresis thresholding.  Note the segmented edge between the soccer
* field and the track.
edges_color (Image, ImaAmpHyst, ImaDirHyst, 'canny', 1, 'nms', 20, 40)
threshold (ImaAmpHyst, RegionColor, 1, 255)
skeleton (RegionColor, EdgesColor)
dev_display (Image)
dev_set_color ('blue')
dev_display (EdgesColor)
Message := 'Segmented color edges'
disp_message (WindowHandle, Message, 'window', 12, 12, 'black', 'true')
stop ()
* Now perform the gray value edge extraction including non-maximum
* suppression and hysteresis thresholding.  Note the absence of an edge
* between the soccer field and the track.
edges_image (GrayImage, ImaAmpGrayHyst, ImaDirGrayHyst, 'canny', 1, 'nms', 20, 40)
threshold (ImaAmpGrayHyst, RegionGray, 1, 255)
skeleton (RegionGray, EdgesGray)
dev_display (GrayImage)
dev_set_color ('blue')
dev_display (EdgesGray)
Message := 'Segmented gray value edges'
disp_message (WindowHandle, Message, 'window', 12, 12, 'black', 'true')
stop ()
* Now display everything again, while only showing the part of the image
* containing the soccer field and the track.
Row1 := 220
Col1 := 215
Row2 := 399
Col2 := 489
dev_set_part (Row1, Col1, Row2, Col2)
dev_display (Image)
stop ()
dev_display (GrayImage)
stop ()
dev_display (ImaAmp)
stop ()
dev_display (ImaAmpGray)
stop ()
dev_display (Image)
dev_set_color ('blue')
dev_display (EdgesColor)
stop ()
dev_display (GrayImage)
dev_set_color ('blue')
dev_display (EdgesGray)

要点

  1. 例程中着重说明图像中足球场和跑道两个区域间几乎没有对比度 。以此为难点分别用edges_coloredges_image分割图像边缘。
    没有对比度意味着灰度化后足球场和跑道区域间边缘特征不明显(看起来像一块区域),后接edges_image 确实没有检测出足球场边框。
    edges_color直接对彩色图像进行边缘提取,效果会好于edges_image方法。两个算子的参数相同,不同点在于入参图像分别为彩色图像和灰度图像。
    edges_color------使用 Deriche、Lanser、Shen 或 Canny 过滤器提取边缘;
    Image ------入参,待处理图像;
    ImaAmp ------出参,边缘幅度(梯度)分割结果;
    ImaDir ------出参,边缘方向分割结果;
    Filter ------入参,过滤器;
    Alpha ------入参,滤镜参数(值越小,平滑效果越强,细节越少,canny算子相反);
    NMS ------入参,极大值抑制;
    Low ------入参,滞后阈值分割的低阈值(不需要则置negative);
    High ------入参,滞后阈值分割的高阈值(不需要则置negative);
相关推荐
澪-sl14 分钟前
基于CNN的人脸关键点检测
人工智能·深度学习·神经网络·计算机视觉·cnn·视觉检测·卷积神经网络
真的想上岸啊36 分钟前
学习C++、QT---18(C++ 记事本项目的stylesheet)
开发语言·c++·学习
rui锐rui1 小时前
大数据学习2:HIve
大数据·hive·学习
凛铄linshuo2 小时前
爬虫简单实操2——以贴吧为例爬取“某吧”前10页的网页代码
爬虫·python·学习
大春儿的试验田3 小时前
高并发收藏功能设计:Redis异步同步与定时补偿机制详解
java·数据库·redis·学习·缓存
金色光环4 小时前
【Modbus学习笔记】stm32实现Modbus
笔记·stm32·学习
THMOM914 小时前
TinyWebserver学习(9)-HTTP
网络协议·学习·http
凌辰揽月5 小时前
Servlet学习
hive·学习·servlet
魔芋红茶6 小时前
spring-initializer
python·学习·spring
西岭千秋雪_6 小时前
Redis性能优化
数据库·redis·笔记·学习·缓存·性能优化