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如何在 C# ASP.NET Core 3.1 中正确检索设备独立位图（DIB）指针作为位图？

问题：当我尝试从 Dib 指针保存位图时，我收到System.AccessViolationException: 'Attempted to read or write protected memory。这通常表明其他内存”

我正在使用以下构造函数 Bitmap(Int32, Int32, Int32, PixelFormat, IntPtr)并假设最终参数可以使用 DIB 指针。

using System.Drawing.Common.dll
Bitmap(Int32, Int32, Int32, PixelFormat, IntPtr)

使用以下语法：


    public class Example
    {
        [DllImport("kernel32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
        public static extern IntPtr GlobalLock(int handle);
            
        //https://stackoverflow.com/questions/2185944/why-must-stride-in-the-system-drawing-bitmap-constructor-be-a-multiple-of-4
        public void GetStride(int width, PixelFormat format, ref int stride, ref int bytesPerPixel)
        {
            int bitsPerPixel = System.Drawing.Image.GetPixelFormatSize(format);
            bytesPerPixel = (bitsPerPixel + 7) / 8;
            stride = 4 * ((width * bytesPerPixel + 3) / 4);
        }
        public Bitmap ConvertDibToBitmap(IntPtr dib)
        {
            IntPtr dibPtr = GlobalLock(dib);

            BITMAPINFOHEADER bmi = (BITMAPINFOHEADER)Marshal.PtrToStructure(dibPtr, typeof(BITMAPINFOHEADER));
            /*
                biBitCount: 24
                biClrImportant: 0
                biClrUsed: 0
                biCompression: 0
                biHeight: 2219
                biPlanes: 1
                biSize: 40
                biSizeImage: 12058624
                biWidth: 1704
                biXPelsPerMeter: 7874
                biYPelsPerMeter: 7874
            */

            //We're able to initalize the object here:
            Bitmap img = new Bitmap(bmi.biWidth, bmi.biHeight, stride, PixelFormat.Format32bppArgb, dibPtr);
            img.Save("OutputTest.bmp");
            /*This line throws the exception "System.AccessViolationException: 'Attempted to read or write protected memory. This is often an indication that other memory"*/

        }
    }

我假设问题在于步幅和/或像素格式的计算。我不确定如何从BITMAPINFOHEADER确定PixelFormat

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