ArcEngine中主要是用ILayerEffects接口对栅格图层的透明度、对比度、亮度进行调整,其中透明度的取值范围为0-100,对比度和亮度的取值范围为-100-100,代码如下:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.DataSourcesFile;
using ESRI.ArcGIS.DataSourcesGDB;
using ESRI.ArcGIS.DataSourcesRaster;
using ESRI.ArcGIS.Display;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Output;
using ESRI.ArcGIS.SystemUI;
namespace WindowsFormsApplication1
{
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
}
// 添加影像数据
private void btnAddData_Click(object sender, EventArgs e)
{
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.Title = "选择栅格文件";
openFileDialog.Filter = "TIFF(*.tif)|*.tif";
openFileDialog.RestoreDirectory = true;
if (openFileDialog.ShowDialog() == DialogResult.OK)
{
IWorkspaceFactory pWorkspaceFactory = new RasterWorkspaceFactory();
IWorkspace pWorkspace = pWorkspaceFactory.OpenFromFile(System.IO.Path.GetDirectoryName(openFileDialog.FileName), 0);
IRasterWorkspace pRasterWorkspace = pWorkspace as IRasterWorkspace;
IRasterDataset pRasterDataset = pRasterWorkspace.OpenRasterDataset(System.IO.Path.GetFileName(openFileDialog.FileName));
// 创建金字塔
IRasterPyramid pRasterPyramid = pRasterDataset as IRasterPyramid;
if (!pRasterPyramid.Present)
{
pRasterPyramid.Create();
}
// 栅格图层
IRasterLayer pRasterLayer = new RasterLayer();
pRasterLayer.CreateFromDataset(pRasterDataset);
ILayer pLayer = pRasterLayer as ILayer;
// 刷新地图
axMapControl1.AddLayer(pLayer, 0);
axMapControl1.Refresh();
}
}
// 调整透明度
private void trackBar1_Scroll(object sender, EventArgs e)
{
IRasterLayer pRasterLayer = axMapControl1.get_Layer(0) as IRasterLayer;
ILayerEffects pLayerEffects = pRasterLayer as ILayerEffects;
pLayerEffects.Transparency = (short)trackBar1.Value;
axMapControl1.ActiveView.Refresh();
}
// 调整对比度
private void trackBar2_Scroll(object sender, EventArgs e)
{
IRasterLayer pRasterLayer = axMapControl1.get_Layer(0) as IRasterLayer;
ILayerEffects pLayerEffects = pRasterLayer as ILayerEffects;
pLayerEffects.Contrast = (short)trackBar2.Value;
axMapControl1.ActiveView.Refresh();
}
// 调整亮度
private void trackBar3_Scroll(object sender, EventArgs e)
{
IRasterLayer pRasterLayer = axMapControl1.get_Layer(0) as IRasterLayer;
ILayerEffects pLayerEffects = pRasterLayer as ILayerEffects;
pLayerEffects.Brightness = (short)trackBar3.Value;
axMapControl1.ActiveView.Refresh();
}
}
}
结果如下图: