壓縮圖片的三種方式
using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Drawing;using System.IO;namespace ConsoleApplication3_ThumbnailImg
{
class Program
{ const int HEIGHT = 190; const int WIDTH = 190; static void Main(string[] args) { string srcImgPath = @"G:\photoes\20060725\Picture 057.jpg"; string targetFolder = @"E:\Diary\Test\thumbnail"; SetThumbnail_1(srcImgPath, targetFolder); SetThumbnail_2(srcImgPath, targetFolder); SetThumbnail_3(srcImgPath, targetFolder); Console.Read();
} static void SetThumbnail_1(string srcImgPath, string targetFolder) { using (Bitmap source = new Bitmap(srcImgPath)) { // return the source image if it's smaller than the designated thumbnail int wi, hi; wi = WIDTH; hi = HEIGHT; // maintain the aspect ratio despite the thumbnail size parameters if (source.Width > source.Height) { wi = WIDTH; hi = (int)(source.Height * ((decimal)WIDTH / source.Width)); } else { hi = HEIGHT; wi = (int)(source.Width * ((decimal)HEIGHT / source.Height)); } using (Image thumb = source.GetThumbnailImage(wi, hi, null, IntPtr.Zero)) { string targetPath = Path.Combine(targetFolder, "th_1.jpg"); thumb.Save(targetPath); } } } static void SetThumbnail_2(string srcImgPath, string targetFolder) { using (Bitmap source = new Bitmap(srcImgPath)) { // return the source image if it's smaller than the designated thumbnail int wi, hi; wi = WIDTH; hi = HEIGHT; // maintain the aspect ratio despite the thumbnail size parameters if (source.Width > source.Height) { wi = WIDTH; hi = (int)(source.Height * ((decimal)WIDTH / source.Width)); } else { hi = HEIGHT; wi = (int)(source.Width * ((decimal)HEIGHT / source.Height)); } // original code that creates lousy thumbnails // System.Drawing.Image ret = source.GetThumbnailImage(wi,hi,null,IntPtr.Zero); using (System.Drawing.Bitmap thumb = new Bitmap(wi, hi)) { using (Graphics g = Graphics.FromImage(thumb)) { g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; g.FillRectangle(Brushes.White, 0, 0, wi, hi); g.DrawImage(source, 0, 0, wi, hi); } string targetPath = Path.Combine(targetFolder, "th_2.jpg"); thumb.Save(targetPath); } } } static void SetThumbnail_3(string srcImgPath, string targetFolder) { //Configure JPEG Compression Engine System.Drawing.Imaging.EncoderParameters encoderParams = new System.Drawing.Imaging.EncoderParameters(); long[] quality = new long[1]; quality[0] = 75; System.Drawing.Imaging.EncoderParameter encoderParam = new System.Drawing.Imaging.EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality); encoderParams.Param[0] = encoderParam; System.Drawing.Imaging.ImageCodecInfo[] arrayICI = System.Drawing.Imaging.ImageCodecInfo.GetImageEncoders(); System.Drawing.Imaging.ImageCodecInfo jpegICI = null; for (int x = 0; x < arrayICI.Length; x++) { if (arrayICI[x].FormatDescription.Equals("JPEG")) { jpegICI = arrayICI[x]; break; } } using (Bitmap source = new Bitmap(srcImgPath)) { int wi, hi; wi = WIDTH; hi = HEIGHT; // maintain the aspect ratio despite the thumbnail size parameters if (source.Width > source.Height) { wi = WIDTH; hi = (int)(source.Height * ((decimal)WIDTH / source.Width)); } else { hi = HEIGHT; wi = (int)(source.Width * ((decimal)HEIGHT / source.Height)); } // original code that creates lousy thumbnails // System.Drawing.Image ret = source.GetThumbnailImage(wi,hi,null,IntPtr.Zero); using (System.Drawing.Bitmap thumb = new Bitmap(wi, hi)) { using (Graphics g = Graphics.FromImage(thumb)) { g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; g.FillRectangle(Brushes.White, 0, 0, wi, hi); g.DrawImage(source, 0, 0, wi, hi); } string targetPath = Path.Combine(targetFolder, "th_3.jpg"); thumb.Save(targetPath, jpegICI, encoderParams); } } } }
}
