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BartMark Bitmap Encoder v 1.2

Encoding a Bitmap

BartMark Bitmap Encoder will allow you to encode text messages into ordinary full color bitmap images or monochrome bitmap images. Encoded bitmaps can be converted to/from various non-lossy formats such as TIFF uncompressed or PNG.

Encoding a color bitmap:
First start the program and open a color bitmap from the file menu.

Next, type your message in the message area. On the status bar below you can see from left to right:
Filename -- Status -- File Type -- Current/Max Message size

If you exceed the maximum message size (in the lower right corner), the message will turn red to let you know you are over. After you have typed your message, you now need to select an encoding key. This key will be needed when you decode the message, so either type in a number you know, or click the Auto button to have it generated for you. If you choose auto, you must remember the number to get your message back.

After you have a number, click the Encode button to Encode the message.

Your message is now embedded in the image. You now need to save the image.
Click the file menu and click Save or Save As.. to save as a different file.

You now have a message saved and hidden in an image. BartMark Bitmap Encoder will work similarly on a Monochrome bitmaps too. Want to get your message back? Go to the decoding section next.

Decoding a Bitmap

Follow these steps to decode a color bitmap:
First start the program and open a color bitmap from the file menu.

Next, click on the Decode Message radio button in the right panel. Now, type in the key that you used to encode the message. If you do not have the correct key, you will not be decoding a message. Enter in the maximum number of characters in your message. This can be greater or less than the actual message size. Note: You must try to keep the Max Chars number as small as possible to decrease the time needed to decode. Entering in 5000 when your message is only likely to be 100 will waste you a lot of time.

Next click the Decode button and notice your message appear in the message area.

Next to save the message, click on Save Message As... on the File menu. This will prompt you to save the message as a text file on your hard drive.

You now have decoded a message from a bitmap. The same can be done with monochrome bitmap images. To destroy a message encoded in a bitmap, you can either encode random characters of the same length using the same key or simply save the image in a lossy format such as JPG.

Frequently Asked Questions

What can I convert a Bitmap to without destroying the message?
BartMark Bitmap Encoder currently only produces fragile watermarks. This means that if the file is changed only slightly , the watermark (your message) will be destroyed. The type of watermark used limits it's use for document validation/ownership except for monochrome bitmaps. Monochrome bitmaps that are converted to/from G4 TIFF are typically not converted to any other formats so BartMark watermarks remain intact.

The following conversions are BartMark OK; they will preserve the message you encode:

Full Color Images (24-Bit):

Bitmap (*.bmp) < - > ZSoft Multi-page Paintbrush (*.dcx)
Bitmap (*.bmp) < - > DKB Ray Tracer (*.dis)
Bitmap (*.bmp) < - > DPX (*.dpx)
Bitmap (*.bmp) < - > Windows Enhanced Metafile (*.emf)
Bitmap (*.bmp) < - > Icon File (*.ico)
Bitmap (*.bmp) < - > Amiga IFF (*.iff)
Bitmap (*.bmp) < - > Vivid Ray Tracer (*.img)
Bitmap (*.bmp) < - > JPEG 2000 JP2 (*.jp2)
Bitmap (*.bmp) < - > JPEG 2000 Code Stream (*.jpc)
Bitmap (*.bmp) < - > Image Magick File (*.mif)
Bitmap (*.bmp) < - > MTV Ray Tracer (*.mtv)
Bitmap (*.bmp) < - > Gimp Pattern (*.pat)
Bitmap (*.bmp) < - > ZSoft Publisher's Paintbrush (*.pcx)
Bitmap (*.bmp) < - > Rayshade (*.pic)
Bitmap (*.bmp) < - > SoftImage (*.pic)
Bitmap (*.bmp) < - > Alias Image File (*.pix)
Bitmap (*.bmp) < - > Portable Network Graphics 24-Bit (*.png)
Bitmap (*.bmp) < - > Portable Image (*.pnm)
Bitmap (*.bmp) < - > Portable Pixmap (*.ppm)
Bitmap (*.bmp) < - > QRT Ray Tracer (*.qrt)
Bitmap (*.bmp) < - > Radiance (*.rad)
Bitmap (*.bmp) < - > Silicon Graphics RGB (*.rgb)
Bitmap (*.bmp) < - > Wavefront Raster File (*.rla)
Bitmap (*.bmp) < - > Truevision Targa (*.tga)
Bitmap (*.bmp) < - > TIFF Various (*.tif, *.tiff)
Bitmap (*.bmp) < - > Vista (*.vst)

Monochrome Images (1-Bit):

Compatible with conversion to most non-lossy and palette-based formats including GIF and TIFF

Why does encoding/decoding large messages take so long?
Encoding and Decoding algorithms in use by BartMark are not linear time based. This means that the more text you try to encode the slower and slower it will become. Encoding over 10,000 characters can prove impossible on all but the fastest processors at the time of this release. Improvements may be made to the algorithms in future releases.

Does BartMark Bitmap Encoder have a Batch Mode?
There is no batch mode available in BartMark Bitmap Encoder. There is, however, a COM object available at http://www.bartdart.com. The COM object is free for non-commercial use and contains all of the functionality of BartMark Bitmap Encoder.

Why can't I Save to a TIFF File?
There are plenty of good TIFF file programs and libraries available for free. If you need to convert and encode many images, consider the BartMark COM object which is compatible with Visual Basic 6 and .NET.