WPF 解決Image控件讀取高分辨率圖片並縮放占用內存過大

需求:讀取高分辨率圖片顯示到寬度為200的Image控件上

核心代碼:

private BitmapImage ReadImageFiletToBinary(string fileName)
{
using (var stream = new FileStream(fileName, FileMode.Open))
{
var bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;

int streamLen = (int)stream.Length;
byte[] imageData = new byte[stream.Length];
stream.Read(imageData, 0, streamLen);

bitmapImage.StreamSource = new MemoryStream(imageData, 0, streamLen);

bitmapImage.DecodePixelWidth = 200; //設置解碼后圖像的寬度，圖像變小，解析變快
bitmapImage.EndInit();
return bitmapImage;
}
}

這樣占用的內存很低,原本直接讀取10幾張圖需要占用150M內存,現在只需不到5M