Internet & Web Page Barcode Tutorial
Implementing internet web barcode technology is often useful for the automation or verification of something that must be displayed on a mobile device screen or printed, such as airline boarding passes and tickets, invoices and receipts, coupons, name badges, check-in confirmations, registrations, rebate mailers, gift certificates and more. IDAutomation offers many products used to generate barcode symbols on the web and in web based mobile apps. These implementations are listed in the charts below, in order, with the recommended options at the top.
A popular method of barcode generation involves streaming an image from a server. This implementation type is supported by several products and may be easily implemented within several applications as described in the Dynamic Streaming Barcode Integration Guide. No temporary files are produced on the host because the resulting barcode image is transmitted immediately to the browser as a binary stream. Printing to low resolution thermal printers is not recommended with streaming products unless a DPI adjustment can be made to match the image to the printer's resolution. Any of these streaming services may also be used as a barcode generator for a desktop or mobile app.
Using barcode fonts within web applications allows very efficient barcode generation without latency issues. In addition, many of IDAutomation's barcode fonts print accurately to low resolution thermal printers. All Code 39 and Codabar barcode fonts require a start and stop character. In addition, more complex barcode fonts such as Code 128, DataBar, PDF417, Data Matrix and QR-Code require implementation of a font encoder.
This product is a Web Server Control designed to be used in ASP.NET Web Applications. It is compatible with Microsoft Visual Studio and other .NET development environments. Many similar barcode symbologies are combined into single, small, fully-functional, redistributable file.
These components are downloaded by the web browser, stored in the browsers cache and used as needed. They allow very efficient barcode generation without latency issues, however, are generally not compatible with all browsers. In addition, security settings may not allow barcode generation from these components.
When displaying barcodes on mobile devices, it is suggested that the barcode symbol be enlarged so it can be accurately scanned from the screen. For best performance on mobile devices, IDAutomation recommends a 2D matrix symbology such as Data Matrix or QR-Code. To properly scan a 2D symbol from a mobile device, a 2D imager should be used, such as the IDAutomation 2D Scanner.
When implementing barcodes on the web, most browsers will print from the screen image at 96 DPI. The low resolution of the browser can sometimes be a problem when barcodes that are being printed require precise X dimensions (the width of the narrow bar). The minimum allowable X dimension (the width of the narrow bar) of a browser barcode that uses a streaming product to display a barcode must be a multiple of 1/96 of an inch, which is about 12 mils, or .03CM.
Most ISO and AIM standards indicate that the minimum X dimension should be 10 mils for open systems (meaning compatibility with different barcode scanners), so this is usually not an issue. However, there are some situations when the X dimension needs to be defined more accurately. For example, if an application requires an X dimension of 5 mils or 15 mils, this problem can be resolved by using products that support this capability such as Barcode Fonts or Web Server Controls. To understand more about this, please refer to the Achieving the Correct X Dimension with Web Products KB article.
Barcode images from browsers can also cause problems when printing to 203 DPI thermal barcode printers. This issue may be resolved by using Barcode Fonts or Web Server Controls. To understand more about this, refer to the Printing to Thermal Barcode Printers with Web Products article.
Laser barcode scanners cannot be used to properly read barcode symbols from screens or mobile devices. Instead a CCD scanner or 2D imager must be used. All of the barcode scanners provided by IDAutomation have built-in decoders that automatically read several barcode types and perform "keyboard emulation" by default. They receive their power from the PC keyboard or USB port so no external power supply is required. When a barcode is scanned with these easy-to-use scanners, the data is sent to the PC as if it had been typed from the keyboard. When the data is sent in keyboard emulation mode, it is possible to use these scanners as easy input devices for online web applications by placing the cursor in the appropriate field and scanning the barcode. Additional information about scanning barcodes into applications is provided in the USB Barcode Scanner Application Integration Guide.