The densities and speeds PaperDisk can achieve vary depending on the capabilities of the scanners, printers, and processors. Yet some current benchmarks are revealing of the potential. Utilizing off-the-shelf printers and scanners, we have succeeded in encoding over 2.4MB of text (over 900 pages, over 660K after compression) on one side of a printed page, and retrieving it perfectly and consistently. Utilizing more precise printing processes and the same off-the-shelf scanner, we have succeeded in encoding 4MB of text (over 1,500 pages, over 1MB after compression) within an 8.5 x 11 inch space. With a 100 MHz Pentium, encoded data has been extracted at speeds up to 20Kbps with compressed data (perhaps 80Kbps uncompressed throughput) -- as fast as all but the fastest modems over ordinary telephone lines.
While we have produced the above densities to demonstrate the potential for the technology, we recommend using lesser densities whenever possible in order to minimize difficulties in decoding the PaperDisk patterns. The PaperDisk software comes with preselected default parameters which vary depending on the intended printer and scanner. These default parameters were selected so that the technology works effortlessly virtually every time. This high degree of reliability comes at the cost of lower densities of data.
If you want to determine the upper limits for your printer and scanner, you can customize your format parameters. Click on the Data format button, then select Customize. This brings you to the Customize data format dialog box. From there you can experiment by setting your own format parameters. The Help facility tells you what the various parameters mean. You might want to start experimenting by lowering parameters such spot height, spot length and row distance by increments of 1. Note that with off-the-shelf peripherals, combinations of 600dpi optical resolution scanners and 600dpi laser printers will produce densities significantly higher than other combinations of printers and scanners. Good luck and, if you are able to better our benchmarks, drop us a line!