Monochrome Bitmap Printing to Zebra ZM400 using ZPL II

Hello,

I am using the following code which I got from a thread online:

// Given a monochrome bitmap file, one can read
// information about that bitmap from the header
// information in the file.  This information includes
// bitmap height, width, bitsPerPixel, etc.  It is required
// that a developer understands the basic bitmap format and
// how to extract the following data in order to proceed.
// A simple search online for 'bitmap format' should yield
// all the needed information.  Here, for our example, we simply
// declare what the bitmap information is, since we are working
// with a known sample file.

string bitmapFilePath = @"test.bmp";  // file is attached to this support article
byte[] bitmapFileData = System.IO.File.ReadAllBytes(bitmapFilePath);
int fileSize = bitmapFileData.Length;

// The following is known about test.bmp.  It is up to the developer
// to determine this information for bitmaps besides the given test.bmp.
int bitmapDataOffset = 62;
int width = 255;
int height = 255;
int bitsPerPixel = 1; // Monochrome image required!
int bitmapDataLength = 8160;
double widthInBytes = Math.Ceiling(width / 8.0);

// Copy over the actual bitmap data from the bitmap file.
// This represents the bitmap data without the header information.
byte[] bitmap = new byte[bitmapDataLength];
Buffer.BlockCopy(bitmapFileData, bitmapDataOffset, bitmap, 0, bitmapDataLength);

// Invert bitmap colors
for (int i = 0; i < bitmapDataLength; i++)
{
    bitmap[i] ^= 0xFF;
}

// Create ASCII ZPL string of hexadecimal bitmap data
string ZPLImageDataString = BitConverter.ToString(bitmap);
ZPLImageDataString = ZPLImageDataString.Replace("-", string.Empty);

// Create ZPL command to print image
string[] ZPLCommand = new string[4];

ZPLCommand[0] = "^XA";
ZPLCommand[1] = "^FO20,20";
ZPLCommand[2] =
    "^GFA, " +
    bitmapDataLength.ToString() + "," +
    bitmapDataLength.ToString() + "," +
    widthInBytes.ToString() + "," +
    ZPLImageDataString;

ZPLCommand[3] = "^XZ";

// Connect to printer
string ipAddress = "10.3.14.42";
int port = 9100;
System.Net.Sockets.TcpClient client =
    new System.Net.Sockets.TcpClient();
client.Connect(ipAddress, port);
System.Net.Sockets.NetworkStream stream = client.GetStream();

// Send command strings to printer
foreach (string commandLine in ZPLCommand)
{
    stream.Write(ASCIIEncoding.ASCII.GetBytes(commandLine), 0, commandLine.Length);
    stream.Flush();
}

// Close connections
stream.Close();
client.Close();

Open in new window


It is working correctly, if I use a monochrome bitmap of the same size as used in this example, but I need to use a smaller monochrome bitmap image, but when I change the width & height above to a smaller image I get the following error:

Error
I have updated the width and height to the smaller image as shown below:

// The following is known about test.bmp.  It is up to the developer
        // to determine this information for bitmaps besides the given test.bmp.
        int bitmapDataOffset = 62;
        int width = 50;
        int height = 50;
        int bitsPerPixel = 1; // Monochrome image required!
        int bitmapDataLength = 8160;
        double widthInBytes = Math.Ceiling(width / 8.0);

Open in new window


...but I need to update the other variables too, I am however unsure of how to get this information of the monochrome bitmap image. Please advise how I can get the other ones from my monochrome bitmap image?

Thanks!
SpaceLaikaAsked:
Who is Participating?
 
Sinisa VukConnect With a Mentor Commented:
You should set bitmapDataLength too, 1 bit per pixel (in one row: (width / 8) bytes):
int bitmapDataLength = ((width / 8) * height);

Open in new window


bitmapDataOffset is not always the same, it is written in header:
http://en.wikipedia.org/wiki/BMP_file_format

int bitmapDataOffset = BitConverter.ToInt32(bitmapFileData, 10);

Open in new window

0
 
DansDadUKConnect With a Mentor Commented:
As sinisav indicates, you need to understand the (various) bitmap header formats, in order to extract the attributes of the image.

The Image Bitmap tool in the PCL Paraphernalia application (available via http://www.pclparaphernalia.eu ) converts common formats of bitmap image to the equivalent PCL raster image.

I've no idea how much PCL raster format differs from ZPL raster format, but the tool may at least give you some help, since (for supported bitmap types) it will display some of the bitmap properties:

width (pixels)
height (pixels)
X-resolution (pixels-per-metre and (derived) pixels-per-inch)
Y-resolution (pixels-per-metre and (derived) pixels-per-inch)
bits-per-pixel
compression mode number
monochrome - true/false


The bitmap image types supported  by the tool are Windows v3 bitmap files, of type BM, which are uncompressed, bottom-up, and either 1-, 4- or 24-bits-per-pixel images.
0
All Courses

From novice to tech pro — start learning today.