更改图像分辨率

本文介绍了更改图像分辨率的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 29岁程序员，3月因学历无情被辞！ 我想将一个上传图片的分辨率更改为小尺寸。如何使用c＃asp.net if （fileUploadImage.HasFile） { int fileSize = fileUploadImage.PostedFile。的ContentLength; if （fileSize > Convert.ToInt32（ConfigurationManager.AppSettings [ fileSize]）） { lblUploadImage.Visible = 真; } else { String fileName = fileUploadImage.FileName.ToString（）; // Substring（0，fileUploadImage.FileName.IndexOf（。））; string fileNameUrl = ConfigurationManager.AppSettings [ imagepath] + GenerateUniqueFileName（txtFname.Text，Path.GetExtension（fileName））; Bitmap upBmp =（Bitmap）Bitmap.FromStream（fileUploadImage.PostedFile.InputStream）; 位图newBmp = 新位图（ 50 ， 50 ，System.Drawing.Imaging.PixelFormat.Format24bppRgb）; newBmp.SetResolution（ 72 ， 72 ）; Graphics newGraphic = Graphics.FromImage（newBmp）; 尝试 { newGraphic.Clear（Color。白色）; newGraphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias; newGraphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; newGraphic.DrawImage（upBmp， 500 ， 100 ， 500 ， 100 ）; newBmp.Save（MapPath（fileNameUrl））; // 在图像控件中显示已上传的已调整大小的图片 imgProfile.Src = fileNameUrl; lblUploadImage.Visible = true ; } catch （Exception exp） {} // fileUploadImage.SaveAs（Server.MapPath（fileNameUrl））; // HiddenField1.Value = fileNameUrl; // imgProfile.Src = fileNameUrl; // lblUploadImage.Visible = false; } 解决方案 您可以查看SetResolution-Method： http://msdn.microsoft.com/de-de/library/ system.drawing.bitmap.setresolution.aspx [ ^ ] 但是，谢尔盖提到你可能想要做的是图像的下采样。 你好，你的代码中有一点错误，但它是如此有用。 你必须保存upBmp对象而不是newBmp对象。 非常感谢!! i want to change the resolution of one uploaded image to small size .how to do this usng c# asp.netif (fileUploadImage.HasFile) { int fileSize = fileUploadImage.PostedFile.ContentLength; if (fileSize > Convert.ToInt32(ConfigurationManager.AppSettings["fileSize"])) { lblUploadImage.Visible = true; } else { String fileName = fileUploadImage.FileName.ToString();//Substring (0,fileUploadImage.FileName.IndexOf(".")); string fileNameUrl = ConfigurationManager.AppSettings["imagepath"] + GenerateUniqueFileName(txtFname.Text, Path.GetExtension(fileName)); Bitmap upBmp = (Bitmap)Bitmap.FromStream(fileUploadImage.PostedFile.InputStream);Bitmap newBmp = new Bitmap(50,50, System.Drawing.Imaging.PixelFormat.Format24bppRgb);newBmp.SetResolution(72, 72); Graphics newGraphic = Graphics.FromImage(newBmp);try {newGraphic.Clear(Color.White);newGraphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;newGraphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;newGraphic.DrawImage(upBmp, 500, 100, 500, 100);newBmp.Save(MapPath(fileNameUrl));//Show the uploaded resized picture in the image controlimgProfile.Src = fileNameUrl;lblUploadImage.Visible = true; } catch(Exception exp) { } // fileUploadImage.SaveAs(Server.MapPath(fileNameUrl)); // HiddenField1.Value = fileNameUrl; // imgProfile.Src = fileNameUrl; // lblUploadImage.Visible = false; } 解决方案 You can have a look at the SetResolution-Method:http://msdn.microsoft.com/de-de/library/system.drawing.bitmap.setresolution.aspx[^]But as Sergey mentioned what you probably want to do is a Downsampling of the image.Hello, you have a little mistake in your code, but it's so helpfully.you must save the upBmp object and not the newBmp object.Thank you so much!! 这篇关于更改图像分辨率的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！ 上岸，阿里云！