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Replace GDI+ DrawImage with PInvoked GDI and transparent PNG's

由 血红的双手。 提交于 2019-11-30 07:31:29

I ended up using SharpDX to access both the WIC and Direct2d API's. The results are impressive to say the least. When compositing with Direct2d I'm seeing increased performance as much as 400-500% over GDI+.

I also tried GDI+ and the Task Parallel Library to break up images into four quandrants and do compositing work in each core. The results weren't nearly as signficant as using SharpDX.

Here's the code I ended up using. The reference to "renderSettings" is just a configuration object. Substitute as needed along with the renderLayer image list. 

/* SharpDX */
using SharpDX;
using SharpDX.Direct2D1;
using SharpDX.DirectWrite;
using SharpDX.DXGI;
using SharpDX.IO;
using SharpDX.WIC;
using AlphaMode = SharpDX.Direct2D1.AlphaMode;
using WicBitmap = SharpDX.WIC.Bitmap;
using D2DPixelFormat = SharpDX.Direct2D1.PixelFormat;
using WicPixelFormat = SharpDX.WIC.PixelFormat;
using Rectangle = System.Drawing.Rectangle;
using Bitmap = System.Drawing.Bitmap;

public Image FlattenImageDirect2d()
{

    List<string> renderLayers = new List<string>()
    {
        "image1.jpg", "image1.png", "image2.png", "image3.png", "image4.png", "image5.png", "image6.png", "image7.png"
    };

    // Base image
    string baseLayer = renderLayers[0];

    // Create WIC and D2D factories
    var wicFactory = new ImagingFactory();
    var ddFactory = new SharpDX.Direct2D1.Factory();

    // Get image size using WIC
    int baseWidth, baseHeight;
    using (var wicStream = new WICStream(wicFactory, renderDirectory + baseLayer, NativeFileAccess.Read)) {
        var jpegDecoder = new JpegBitmapDecoder(wicFactory);
        jpegDecoder.Initialize(wicStream, DecodeOptions.CacheOnDemand);
        var frame = jpegDecoder.GetFrame(0);
        baseWidth = frame.Size.Width;
        baseHeight = frame.Size.Height;
        frame.Dispose();
        jpegDecoder.Dispose();
    }

    // Resize image?
    bool resizeImage = (baseWidth != renderSettings.RenderWidth) || (baseHeight != renderSettings.RenderHeight);

    // Bitmaps and render target settings
    var wicBitmap = new WicBitmap(wicFactory, renderSettings.RenderWidth, renderSettings.RenderHeight, SharpDX.WIC.PixelFormat.Format32bppBGR, BitmapCreateCacheOption.CacheOnLoad);
    var renderTargetProperties = new RenderTargetProperties(RenderTargetType.Default, new D2DPixelFormat(Format.Unknown, AlphaMode.Unknown), 0, 0, RenderTargetUsage.None, FeatureLevel.Level_DEFAULT);
    var wicRenderTarget = new WicRenderTarget(ddFactory, wicBitmap, renderTargetProperties);

    // Create bitmap render target used to draw all images to
    SharpDX.Direct2D1.BitmapRenderTarget bitmapRenderTarget = new SharpDX.Direct2D1.BitmapRenderTarget(wicRenderTarget, CompatibleRenderTargetOptions.None, new D2DPixelFormat(Format.Unknown, AlphaMode.Premultiplied));

    // Draw render layers
    for (int i = 0; i < renderLayers.Count; i++) {
        // First layer is always a jpeg, all other subsequent layers are png's
        ImageFormat imageFormat = (i == 0) ? ImageFormat.Jpeg : ImageFormat.Png;

        using (SharpDX.WIC.BitmapSource bitmapSource = LoadWicBitmap(wicFactory, renderDirectory + renderLayers[i], imageFormat, resizeImage, renderSettings.RenderWidth, renderSettings.RenderHeight)) {

            // Convert WIC pixel format to D2D1 format
            var formatConverter = new FormatConverter(wicFactory);
            formatConverter.Initialize(bitmapSource, SharpDX.WIC.PixelFormat.Format32bppPBGRA, BitmapDitherType.None, null, 0f, BitmapPaletteType.MedianCut);

            // Create direct 2d bitmap from wic bitmap
            SharpDX.Direct2D1.Bitmap direct2DBitmap = SharpDX.Direct2D1.Bitmap.FromWicBitmap(bitmapRenderTarget, formatConverter);

            // Draw direct2d image to bitmap render target
            wicRenderTarget.BeginDraw();
            wicRenderTarget.DrawBitmap(direct2DBitmap, 1.0f, SharpDX.Direct2D1.BitmapInterpolationMode.Linear);
            wicRenderTarget.EndDraw();

            // Clean up
            formatConverter.Dispose();
            direct2DBitmap.Dispose();
        }
    }

    // Final image data
    byte[] imageData;

    // Create streams to write output to. 
    using (var memoryStream = new MemoryStream()) {
        using (var wicStream = new WICStream(wicFactory, memoryStream)) {

            // Encode wic bitmap
            var encoder = new JpegBitmapEncoder(wicFactory);
            encoder.Initialize(wicStream);

            var frameEncoder = new BitmapFrameEncode(encoder);
            frameEncoder.Initialize();
            frameEncoder.SetSize(renderSettings.RenderWidth, renderSettings.RenderHeight);
            frameEncoder.PixelFormat = WicPixelFormat.FormatDontCare;
            frameEncoder.WriteSource(wicBitmap);
            frameEncoder.Commit();
            encoder.Commit();

            // Set image data
            memoryStream.Position = 0;
            imageData = memoryStream.ToArray();

            // Clean up 
            frameEncoder.Dispose();
            encoder.Dispose();
            wicBitmap.Dispose();
            wicRenderTarget.Dispose();
            bitmapRenderTarget.Dispose();
            ddFactory.Dispose();
            wicFactory.Dispose();
            frameEncoder = null;
            encoder = null;
            wicBitmap = null;
            wicRenderTarget = null;
            bitmapRenderTarget = null;                  
            ddFactory = null;
            wicFactory = null;
        }
    }

    return Image.FromStream(new MemoryStream(imageData));
}

private BitmapSource LoadWicBitmap(ImagingFactory wicFactory, string path, ImageFormat imageFormat, bool resize, int resizeWidth = 0, int resizeHeight = 0)
{
    PngBitmapDecoder pngDecoder;
    JpegBitmapDecoder jpegDecoder;
    BitmapFrameDecode bitmapFrameDecode;

    var stream = new WICStream(wicFactory, path, NativeFileAccess.Read);

    // Load the appropriate decoder
    if (imageFormat == ImageFormat.Jpeg) {
        jpegDecoder = new JpegBitmapDecoder(wicFactory);
        jpegDecoder.Initialize(stream, DecodeOptions.CacheOnLoad);
        bitmapFrameDecode = jpegDecoder.GetFrame(0);
        jpegDecoder.Dispose();
    }
    else {
        pngDecoder = new PngBitmapDecoder(wicFactory);
        pngDecoder.Initialize(stream, DecodeOptions.CacheOnDemand);
        bitmapFrameDecode = pngDecoder.GetFrame(0);
        pngDecoder.Dispose();
    }

    // Clean up
    stream.Dispose();

    // Resize if necessary
    if (resize) {
        // Prepare scaler
        var scaler = new BitmapScaler(wicFactory);
        scaler.Initialize(bitmapFrameDecode, resizeWidth, resizeHeight, SharpDX.WIC.BitmapInterpolationMode.Fant);
        return (BitmapSource)scaler;
    }

    return (BitmapSource)bitmapFrameDecode;
}

This one should work:

    private Bitmap GetImage() {
        //##################### Get the Bitmaps ############################
        Bitmap sourceImage = new Bitmap("c:\\1.png");
        Bitmap overlayImage = new Bitmap("c:\\2.png");

        //##################### Get Hdc from baselayer ############################
        Graphics sourceImageGraphics = Graphics.FromImage(sourceImage);
        IntPtr sourceImageHDC = sourceImageGraphics.GetHdc();

        //##################### Get Cdc from second layer ############################
        IntPtr overlayImageCDC = CreateCompatibleDC(sourceImageHDC);
        IntPtr overlayImageHandle = overlayImage.GetHbitmap();
        SelectObject(overlayImageCDC, overlayImageHandle);

        /*
         * BitBlt from sourceImage is not neccessary,
         * because Graphics.FromImage(sourceImage) already did it for you
        */

        //##################### Draw the second layer ############################
        AlphaBlend(sourceImageHDC, 0, 0, overlayImage.Width, overlayImage.Height, overlayImageCDC, 0, 0, overlayImage.Width, overlayImage.Height, new BLENDFUNCTION(AC_SRC_OVER, 0, 0xff, AC_SRC_ALPHA));

        //##################### Release everthing ############################
        sourceImageGraphics.ReleaseHdc(sourceImageHDC);
        sourceImageGraphics.Dispose();

        DeleteDC(overlayImageCDC);
        DeleteObject(overlayImageHandle);

        //##################### Return Image ############################
        return sourceImage;
    }
标签
gdi+
direct2d
wic
sharpdx
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