/// <summary>
/// 根据单波段拉伸渲染
/// </summary>
/// <param name="rasterDataset">栅格数据集</param>
/// <param name="graypos">第几波段</param>
/// <param name="stretchType">拉伸方式</param>
/// <param name="pFromColor">fromColor</param>
/// <param name="pToColor">toColor</param>
/// <returns></returns>
public static IRasterRenderer StretchRenderer(ESRI.ArcGIS.Geodatabase.IRasterDataset rasterDataset, int graypos,
esriRasterStretchTypesEnum stretchType, IRgbColor pFromColor, IRgbColor pToColor)
{
try
{
//Create the color ramp.
IAlgorithmicColorRamp colorRamp = new AlgorithmicColorRampClass();
colorRamp.Size = 255;
colorRamp.FromColor = pFromColor;
colorRamp.ToColor = pToColor;
bool createColorRamp;
colorRamp.CreateRamp(out createColorRamp);
//Create a stretch renderer.
IRasterStretchColorRampRenderer stretchRenderer = new
RasterStretchColorRampRendererClass();
IRasterRenderer rasterRenderer = (IRasterRenderer)stretchRenderer;
//Set the renderer properties.
IRaster raster = rasterDataset.CreateDefaultRaster();
rasterRenderer.Raster = raster;
rasterRenderer.Update();
stretchRenderer.BandIndex = graypos;
stretchRenderer.ColorRamp = colorRamp;
//Set the stretch type.
IRasterStretch pRasterStretch = (IRasterStretch)rasterRenderer;
pRasterStretch.StretchType = stretchType;
pRasterStretch.StandardDeviationsParam = 2;
return(rasterRenderer);
}
catch
{
return(null);
}
}
private void DisplayBandComForm_Load(object sender, EventArgs e)
{
//初始化拉伸方法
List <string> temp = new List <string>();
temp.Add("直方图均衡化");
temp.Add("标准差");
temp.Add("最大最小值");
temp.Add("百分比截断");
this.comBox_StretchType.DataSource = temp;
this.comBox_StretchType.SelectedIndex = 0;
this.stretchType = esriRasterStretchTypesEnum.esriRasterStretch_NONE;
//根据波段数显示不同界面
this.nBand = TOCRightLayer.BandCount;
if (this.nBand == 1)
{
this.panel_multi.Visible = false;
this.panel_single.Visible = true;
}
else
{
List <string> bandnames = new List <string>();
bandnames = getBandName(TOCRightLayer);
addToCombox(this.comBox_B, bandnames);
addToCombox(this.comBox_G, bandnames);
addToCombox(this.comBox_R, bandnames);
this.panel_single.Visible = false;
this.panel_multi.Visible = true;
}
}
private void btn_Display_Click(object sender, EventArgs e)
{
switch (this.comBox_StretchType.SelectedValue.ToString())
{
case "直方图均衡化":
this.stretchType = esriRasterStretchTypesEnum.esriRasterStretch_HistogramEqualize;
break;
case "标准差":
this.stretchType = esriRasterStretchTypesEnum.esriRasterStretch_StandardDeviations;
break;
case "最大最小值":
this.stretchType = esriRasterStretchTypesEnum.esriRasterStretch_MinimumMaximum;
break;
case "百分比截断":
this.stretchType = esriRasterStretchTypesEnum.esriRasterStretch_PercentMinimumMaximum;
break;
}
if (this.nBand == 1)//单波段拉伸显示
{
drawImage(this.TOCRightLayer.Name.ToString(), this.axMapControl.Extent);
this.axMapControl.Refresh();
this.axTOCControl.Refresh();
}
else
{
//如果选择的不够三个波段，无法进行彩色合成
if (this.comBox_B.Text.Length == 0 || this.comBox_G.Text.Length == 0 || this.comBox_R.Text.Length == 0)
{
MessageBox.Show("请选择进行彩色合成的波段！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Warning);
return;
}
this.rgbPos[0] = this.comBox_R.SelectedIndex;
this.rgbPos[1] = this.comBox_G.SelectedIndex;
this.rgbPos[2] = this.comBox_B.SelectedIndex;
drawImage(this.TOCRightLayer.Name.ToString(), this.axMapControl.Extent);
this.axMapControl.Refresh();
this.axTOCControl.Refresh();
}
}
/// <summary>
/// 获取拉伸类型
/// </summary>
/// <param name="stretchType">类型名</param>
/// <returns></returns>
public static esriRasterStretchTypesEnum GetStretchType(string stretchType)
{
//默认标准差拉伸类型
esriRasterStretchTypesEnum schType = esriRasterStretchTypesEnum.esriRasterStretch_StandardDeviations;
switch (stretchType)
{
case "None":
schType = esriRasterStretchTypesEnum.esriRasterStretch_NONE;
break;
case "Custom":
schType = esriRasterStretchTypesEnum.esriRasterStretch_Custom;
break;
case "StandardDeviations":
schType = esriRasterStretchTypesEnum.esriRasterStretch_StandardDeviations;
break;
case "HistogramEqualize":
schType = esriRasterStretchTypesEnum.esriRasterStretch_HistogramEqualize;
break;
case "MinimumMaximum":
schType = esriRasterStretchTypesEnum.esriRasterStretch_MinimumMaximum;
break;
case "HistogramSpecification":
schType = esriRasterStretchTypesEnum.esriRasterStretch_HistogramSpecification;
break;
case "PercentClip":
schType = esriRasterStretchTypesEnum.esriRasterStretch_PercentMinimumMaximum;
break;
}
return(schType);
}
/// <summary>
/// 拉伸渲染
/// </summary>
/// <param name="rasterLayer">渲染图层</param>
/// <param name="stretType">拉伸类型</param>
/// <param name="pStyleGalleryItem">颜色带样式</param>
public static void RasterStretchRenderer(IRasterLayer rasterLayer, esriRasterStretchTypesEnum stretType,
IStyleGalleryItem pStyleGalleryItem)
{
if (pStyleGalleryItem == null)
{
MessageBox.Show(@"Color ramp cannot be empty");
return;
}
//创建拉伸渲染
IRasterStretchColorRampRenderer stretchRenderer = new RasterStretchColorRampRendererClass();
IRasterRenderer rasterRenderer = (IRasterRenderer)stretchRenderer;
//设置拉伸渲染参数属性
IRaster raster = rasterLayer.Raster;
rasterRenderer.Raster = raster;
rasterRenderer.Update();
stretchRenderer.BandIndex = 0;
stretchRenderer.ColorRamp = RenderHelper.GetColorRamp(pStyleGalleryItem, 255);
//设置拉伸类型
IRasterStretch stretchType = (IRasterStretch)rasterRenderer;
stretchType.StretchType = stretType;
rasterLayer.Renderer = rasterRenderer;
}
