Code sample for image loading

During the image loading, .NET specific problems can occur.

The image is encapsulated in System.Drawing.Bitmap object in application memory. The bitmap data has to be transferred in byte[] array to kRecLoadImgM.
BitmapData.Stride is a signed number:

Positive value means TOP_DOWN, and negative value means BOTTOM_UP. The sign of Stride is mapped into lineord of kRecSetImgFormat.

BytesPerLine is the absolute value of Stride.
.NET and OmniPage SDK interprets differently the RGB order:
- Bitmap.PixelFormat Rgb means BGR for kRecLoadImgM
- Bitmap.PixelFormat Argb means BGRA for kRecLoadImgM

The following code sample can be used to load a bitmap image from the memory:

    //Image is received in argument (Bitmap bmp)
    Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);
    BitmapData bmpData = bmp.LockBits(rect, ImageLockMode.ReadOnly, bmp.PixelFormat);
    IMG_LINEORDER imgLineOrder = bmpData.Stride < 0 ? IMG_LINEORDER.BOTTOM_UP : IMG_LINEORDER.TOP_DOWN;
    IMG_INFO ImgInfo = new IMG_INFO();
    ImgInfo.Size.cx = bmp.Width;
    ImgInfo.Size.cy = bmp.Height;
    ImgInfo.DPI.cx = (Int32)bmp.HorizontalResolution;
    ImgInfo.DPI.cy = (Int32)bmp.VerticalResolution;
    ImgInfo.BytesPerLine = (uint)Math.Abs(bmpData.Stride);
    byte[] buf = new byte[Math.Abs(bmpData.Stride) * bmp.Height];
    Marshal.Copy(bmpData.Scan0, buf, 0, buf.Length);
    bmp.UnlockBits(bmpData);
    switch (bmp.PixelFormat){
        case PixelFormat.Format24bppRgb: 
            ImgInfo.BitsPerPixel = 24;
            RecAPI.kRecSetImgFormat(0, imgLineOrder, IMG_PADDING.PAD_DWORDBOUNDARY, IMG_RGBORDER.COLOR_BGR);
            break;
    }
    RecAPI.kRecLoadImgM(0, buf, ImgInfo, out hPage);

Code sample for image loading

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