中国最大的门户网站是,汉阳网站推广公司,东莞中小企业网站制作,受欢迎的聊城网站建设例程功能 演示如何使用edges_color#xff0c;展示只能从彩色图像中提取某些边缘的图像#xff0c;说明edges_color和edges_image输出之间的差异。
代码如下
dev_update_off ()
read_image (Image, olympic_stadium)
get_image_size (Image, Width, Height)
dev_close_wind…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_color和edges_image输出之间的差异。
代码如下
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
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_color和edges_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)
