¿Cómo puedo crear un mapa de bits con una altura de barra específica?

¿Cómo puedo crear un mapa de bits con una altura de barra específica?

El siguiente código de ejemplo muestra cómo crear un mapa de bits con una altura de barra concreta para EAN 13 (se puede adaptar a otros tipos de código de barras lineales).

double dpi = 300;
double barHeightinMM = 23;
double symbolHeightinMM = 26;
double nominalNarrowBarWidthinMM = 0.33;

Graphics gfx = this.CreateGraphics(); // graphics of any screen DC

Barcode ean13 = new Barcode();
ean13.BarcodeType = BarcodeType.Ean13;
ean13.Data = "123456789012";
ean13.Dpi = dpi;

// 1 Pixel in mm
double PxtoMm = 25.4 / dpi;

// how many Pixels are 0.33 mm => We have to round depending on DPI
int narrowBarinPx = (int) Math.Round (nominalNarrowBarWidthinMM / PxtoMm);
double narrowBarinMM = narrowBarinPx * PxtoMm;
System.Diagnostics.Debug.WriteLine("Narrow bar width in mm (rounded to full Pixels): " + narrowBarinMM);

// calculate width in pixels by using the number of "modules" in the barcode
int symbolWidthinPixels = ean13.CalculateNumberOfModules() * narrowBarinPx;

// set font size to an automatic size based upon module width
double fontSizePt = 10 * Math.Round(narrowBarinMM, 3) / 0.339;
ean13.Font = new Font("Consolas", (float) fontSizePt);

// Case A: desired bar height is 23 mm
{
    int barHeightinPx = (int) Math.Round(barHeightinMM / PxtoMm, 0);
    System.Diagnostics.Debug.WriteLine("Bar height in Pixels : " + barHeightinPx);

    // calculate actual text area height
    float textAreaHeightMM = ean13.CalculateTextAreaHeight(null);
    int textAreaHeightPx = (int) (0.5 + textAreaHeightMM / PxtoMm);
    System.Diagnostics.Debug.WriteLine("Text height in Pixels: " + textAreaHeightPx);

    int symbolHeightinPx = barHeightinPx + textAreaHeightPx;

     // set bounding rectangle in Pixels
    ean13.BoundingRectangle = new Rectangle(0,0, symbolWidthinPixels, symbolHeightinPx);

    // Draw directly to bitmap file
    ean13.Draw(AppDomain.CurrentDomain.BaseDirectory + @"\EAN13-caseA.BMP", ImageType.Bmp, gfx, 1);

    // Draw to Picture Box

    // Option A
    // scale font depending on DPI ratio (required if internal DC is used)
    ean13.FontHeight = (int) (fontSizePt * dpi / gfx.DpiY);
    pictureBoxEAN13.Image = ean13.DrawBitmap();

    // Option B
    // ignore DC resolution + use Pt font size
    ean13.IgnoreDpiFromDC = true;
    ean13.FontHeight = (int) fontSizePt;
    pictureBoxEAN13.Image = ean13.DrawBitmap();
}

// Case B: desired symbol height (incl. text) is 26 mm
{
    int symbolHeightinPx = (int) Math.Round (symbolHeightinMM / PxtoMm, 0);
    System.Diagnostics.Debug.WriteLine("Symbol height in Pixels : " + symbolHeightinPx);

     // set bounding rectangle in Pixels
    ean13.BoundingRectangle = new Rectangle(0, 0, symbolWidthinPixels, symbolHeightinPx);

    // Draw directly to bitmap file
    ean13.Draw(AppDomain.CurrentDomain.BaseDirectory + @"\EAN13-caseB.BMP", ImageType.Bmp, gfx, 1);
}