Bitmap & Texture2D 互转方法搜集

来源：互联网发布：php import 编辑：程序博客网时间：2024/06/16 08:15

最近学习emgucv，我在写读摄像头的程序然后需要bitmap 转texture2D 其实可以直接使用setdata<bytes>的方法赋值，感觉帧率不是一般的低，是无法忍受的。

也试了多种方法，基本上都是无法忍受的。可能有人会用得到，将搜集的列下来。

这是一些方法的搜集。

Texture2D toBitmap 的方法

public static Bitmap FastTextureToBitmap(Texture2D texture)         {             // Setup pointer back to bitmap             Bitmap newBitmap = new Bitmap(texture.Width, texture.Height);             // Get color data from the texture             Microsoft.Xna.Framework.Graphics.Color[ textureColors = GetColorDataFromTexture(texture);             System.Drawing.Imaging.BitmapData bmpData = newBitmap.LockBits(new System.Drawing.Rectangle(0, 0, newBitmap.Width, newBitmap.Height), System.Drawing.Imaging.ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);             // Loop through pixels and set values             unsafe             {                 byte* bmpPointer = (byte*)bmpData.Scan0;                 for (int y = 0; y < texture.Height; y++)                 {                     for (int x = 0; x < texture.Width; x++)                     {                         bmpPointer[0] = textureColors[x + y * texture.Width].B;                         bmpPointer[1] = textureColors[x + y * texture.Width].G;                         bmpPointer[2] = textureColors[x + y * texture.Width].R;                         bmpPointer[3] = textureColors[x + y * texture.Width].A;                         bmpPointer += 4;                     }                     bmpPointer += bmpData.Stride - (bmpData.Width * 4);                 }             }             textureColors = null;             newBitmap.UnlockBits(bmpData);             return newBitmap;         }

bitmap to texture2D 的方法：

  private Texture2D GetTexture(GraphicsDevice dev, System.Drawing.Bitmap bmp)        {            int[] imgData = new int[bmp.Width * bmp.Height];            Texture2D texture = new Texture2D(dev, bmp.Width, bmp.Height);            unsafe            {                // lock bitmap                System.Drawing.Imaging.BitmapData origdata =                    bmp.LockBits(new System.Drawing.Rectangle(0, 0, bmp.Width, bmp.Height), System.Drawing.Imaging.ImageLockMode.ReadOnly, bmp.PixelFormat);                uint* byteData = (uint*)origdata.Scan0;                // Switch bgra -> rgba                for (int i = 0; i < imgData.Length; i++)                {                    byteData[i] = (byteData[i] & 0x000000ff) << 16 | (byteData[i] & 0x0000FF00) | (byteData[i] & 0x00FF0000) >> 16 | (byteData[i] & 0xFF000000);                }                // copy data                System.Runtime.InteropServices.Marshal.Copy(origdata.Scan0, imgData, 0, bmp.Width * bmp.Height);                byteData = null;                // unlock bitmap                bmp.UnlockBits(origdata);            }            texture.SetData(imgData);            return texture;        }

貌似对于赋值这一步C#的效率好像不高，帧率一般都会降的很低。我还没有想到更好的办法，表示无奈中。。。

实际上还有一个方法可以直接使用

BitmapSourceExtensions.CopyTo Method (BitmapSource, Texture2D)

此方法需要使用 System.Windows.Media.Imaging 我倒还没有尝试过。估计应该是挺好用的。

例子可以参见http://msdn.microsoft.com/en-us/library/gg712857(v=vs.96).aspx

这种方法试过，但是不管用，自己也是新手，搞不定了。。。就扔了，有人搞懂的话，可以回个帖。~

值得一提的是对于BITMAP的格式，要值得仔细查看一下，不要直接套用上面的方法

这个是另外一种方法，试了一下貌似帧率有所提高，但依然还是不如窗体直接用的那种性能好。都准备放弃XNA了。。。

 1publicstatic Texture2D BitmapToTexture2D( 2 GraphicsDevice GraphicsDevice, 3 System.Drawing.Bitmap image) 4{ 5 // Buffer size is size of color array multiplied by 4 because6// each pixel has four color bytes7int bufferSize = image.Height * image.Width * 4; 8 9 // Create new memory stream and save image to stream so10// we don't have to save and read file 11 System.IO.MemoryStream memoryStream = 12 new System.IO.MemoryStream(bufferSize);13 image.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Png); 14 15 // Creates a texture from IO.Stream - our memory stream16 Texture2D texture = Texture2D.FromStream( 17 GraphicsDevice, memoryStream); 18 19return texture;20}

我依然觉得这是个性能瓶颈。。。又搜到了国外某人发的一个类

using System;using Microsoft.Xna.Framework;using Microsoft.Xna.Framework.Graphics;using System.Drawing;using System.Drawing.Imaging;using System.Runtime.InteropServices;namespace MrXNAHelper{    public class ImageToTexture    {        byte[] bmpBytes;        Texture2D background;        int width, height;        Game game;        public ImageToTexture(Game game, int width, int height)        {            this.width = width;            this.height = height;            this.game = game;            GenerateBitmap(game, width, height);        }        public ImageToTexture(Game game)        {            this.game = game;        }        private void GenerateBitmap(Game game, int width, int height)        {            background = new Texture2D(game.GraphicsDevice, width, height);        }        public Texture2D ConvertBitmapToTexture(Bitmap b)        {                game.GraphicsDevice.Textures[0] = null;                if (background == null ||                    b.Width != background.Width ||                    b.Height != background.Height)                {                    width = b.Width;                    height = b.Height;                    GenerateBitmap(game, width, height);                }                                BitmapData bData = b.LockBits(new System.Drawing.Rectangle(new System.Drawing.Point(), b.Size),                    ImageLockMode.ReadOnly,                    PixelFormat.Format32bppRgb);                // number of bytes in the bitmap                int byteCount = bData.Stride * b.Height;                if (bmpBytes == null ||                    bmpBytes.Length != byteCount)                    bmpBytes = new byte[byteCount];                // Copy the locked bytes from memory                Marshal.Copy(bData.Scan0, bmpBytes, 0, byteCount);                // don't forget to unlock the bitmap!!                b.UnlockBits(bData);                background.SetData(bmpBytes);            return background;        }    }}

我终于会插代码了，，，，囧

现在知道降低XNA帧率或者自己写个定时器，总之不要使用60Hz的话，好像帧率也会有很大的提高。

byte[] bgrData = nextFrame.Bytes;                    for (int i = 0; i < colorData.Length; i++)                        colorData[i] = new Color(bgrData[3 * i + 2], bgrData[3 * i + 1], bgrData[3 * i]);

惊人也没有用到什么内存指针之类的，但是就做到了。使用2张贴图交错的加载方法。膜拜老外啊。