Question

我使用此代码在文件BMP中编写字节数组：

private async void ScriviBMP()
    {
        using (Stream stream = immagineBitmap.PixelBuffer.AsStream())
        {
            await stream.WriteAsync(arrayImmagine, 0, arrayImmagine.Length);
        }
        StorageFolder folder = KnownFolders.PicturesLibrary;
        if (folder != null)
        {
            StorageFile file = await folder.CreateFileAsync("area2_128x128" + ".bmp", CreationCollisionOption.ReplaceExisting);
            using (var storageStream = await file.OpenAsync(FileAccessMode.ReadWrite))
            {
                var encoder = await BitmapEncoder.CreateAsync(BitmapEncoder.BmpEncoderId, storageStream);
                var pixelStream = immagineBitmap.PixelBuffer.AsStream();
                var pixels = new byte[pixelStream.Length];
                await pixelStream.ReadAsync(pixels, 0, pixels.Length);
                encoder.SetPixelData(BitmapPixelFormat.Bgra8, BitmapAlphaMode.Ignore, (uint)immagineBitmap.PixelWidth, (uint)immagineBitmap.PixelHeight, 48, 48, pixels);
                await encoder.FlushAsync();
            }
        }
    }

然后我使用此代码在Image对象中显示BMP图像

private async void VisBMP()
    {
        var file = await KnownFolders.PicturesLibrary.GetFileAsync("area2_128x128.bmp");
        using (var fileStream = (await file.OpenAsync(Windows.Storage.FileAccessMode.Read)))
        {
            var bitImg = new BitmapImage();
            //bitImg.UriSource = new Uri(file.Path);
            bitImg.SetSource(fileStream);
            image.Source = bitImg;
        }
    }

这些功能大约需要400毫秒才能完成整个过程，这需要很多时间。有没有办法避免使用BMP文件并仅使用流来显示图像对象上的图像？调试程序可能会减慢进程的速度吗？我正在使用Visual Studio 2015。

Answer 1

您可以将数据缓冲区（arrayImmagine）传输到 InMemoryRandomAccessStream 中的图像。这些代码大约需要200ms。我使用以下代码测试。此外，您可以参考此article以获取更多信息。

        BitmapImage biSource = new BitmapImage();
        using (InMemoryRandomAccessStream stream = new InMemoryRandomAccessStream())
        {
            await stream.WriteAsync(bytes.AsBuffer());
            stream.Seek(0);
            await biSource.SetSourceAsync(stream);
        }

        image.Source = biSource;

从Byte数组创建一个BitmapImage并将其显示在Image对象UWP Raspberry Pi 3

1 个答案: