Thursday, September 19, 2013

Linear Barcodes; Advantages and Disadvantages

read the first part here

Linear Barcodes

Linear barcodes are commonly referred as first generation barcodes. These barcodes consist of vertical lines at specific gaps resulting in a particular pattern.  Hardware scanners are used to scan these patterns and decode the information stored in those particular patterns. These barcodes are also commonly called discrete, one dimensional or UPC barcodes. The examles of linear barcodes are  Code 39, EAN-8, EAN-13, EAN 128UPC-E,  UPC-A, ISBN etc.

Advantages of Linear Barcodes

In linear barcodes, vertical lines are used to store data; hence data is generated in one direction which is easier to generate as compared to generating data in multi-dimensions.
Linear barcodes are easier to scan. Just like barcode generation, barcode decoding is also done in one direction which is easier to perform.
No special hardware or software is required to scan these barcodes and a simple and inexpensive scanner can be used to generate and scan linear barcodes.

Disadvantages of Linear Barcodes

Linear barcodes can only store small amount of data. In order to store large amount of data in linear barcodes, it has to be stretched horizontally with additional vertical lines and spaces resulting in large barcodes.
Barcode, once distorted cannot be scanned correctly. Small damage, line at the start or end of the barcode can modify or destroy the data stored in the barcode.

to be continued

Monday, September 16, 2013

Code 39 - Limitations and Usage

read the first part here


It is not suitable for items which require large amount of information to be encoded. In that case, length of the code 39 barcode becomes too large which is not appropriate for encoding as well as decoding.
Code 39 barcode can be easily damaged and distorted like any linear barcode.


Code 39 is commonly used in store items, inventories, badges and similar everyday items.
It is widely used in health sector and medical equipment.
Used by the US Defense department (LOGMARS) for the military equipment.
Used in airline and aviation industry on air plane parts.


Code 39 barcode should be used when small amount of information needs to be encoded.

With the help of Bytescout BarCode SDK one is able to generate Code 39, BarCode Reader SDK can decode it.

Thursday, September 12, 2013

Linear and 2-D Barcodes

Linear and 2-D Barcodes

Barcodes have now become an essential part of almost every Brick and Mortar Company. You will rarely find a product without a barcode Tag. Different types of barcodes are used for different purposes in business sectors. There are several advantages of using barcodes as compared to manual data entry. Typical usage of barcodes include

Tracking sale and purchase of large number of items in an inventory.
Barcodes are pasted sports tickets which allow one to enter a sports arena.
Barcodes are often placed on gift tokens that when decoded tells which gift that token corresponds.

There are several reasons to prefer Barcodes over manual data entry. Following are some of the advantages of barcodes over manual data entry
Barcodes are extremely fast to generate and read.
Barcodes eliminate the possibility of human error in data entry.
Wide variety of barcodes exists which serve different purposes, they are extremely versatile.

Types of barcodes

There are two major types of barcodes
1- Linear Barcodes
2- 2-D Barcodes

to be continued

Thursday, September 05, 2013

Code 39 - History, Purposes and Advantages

Code 39

Code 39 is one of the most widely and commonly used barcode type. It is a linear or 1d barcode and is also known as USS code 39, code 3 of 9, Alpha 39, USD-3, and Type 39. Code 39 is capable of encoding all the alphanumeric characters (26 Alphabets and 10 numeric characters ranging from 0 to 9).  It can also encode space and six special characters including dollar sign ($), Period (.), minus (-), percent (%), slash (/), plus (+). Asterisk (*) can also be used but only at the start or end of the code.


Code 39 was initially designed by two researchers from Intermec, named Ray Stevens and Dr.David Allais in the year 1974. Initial code 39 was created with two wide black bars and a wide space which could encode 40 characters excluding the first or last symbol resulting in 39 total characters. It is for this reason that this barcode is called code 39. The latest code 39 contains 9 bars in total with three wide and six narrow bars.


Code 39 has been recognized by ANSI (American National Standards institute) as MH10.8M-1983. It is general purpose and most widely used barcode type. Its basic purpose is to encode small amount of information containing alphabets as well as numeric characters in linear pattern of bars and spaces.


Wide use of this barcode type makes it portable. This barcode can be encoded and decoded by almost every barcode encoding/decoding equipment.
Code 39 can encode all 26 Alphabets of the English language and the numerals which was not possible with the previous barcodes.
It is much more secure and is not prone to faulty encoding and decoding.

to be continued

Wednesday, September 04, 2013

Code 128 Barcodes: History, Purpose, Advantages, Limitations, Applications

Code 128

Code 128 is another linear barcode which is widely used in industry and stores. Code 128 is denser than the other linear barcode type i-e code 39. Code 128 can encode all the upper and lower case alphabets and all the numeric characters from 0-9 and all the 128 ASCII character. The higher density of code 128 makes it suitable to store large amount of data as compared to code 139.
This variety of characters has been categorized into three sub-groups or sub-sets.  Group or subset A contains all the ASCII characters, uppercase characters, digits and control codes.Subset B contains ASCII characters, upper and lower case characters and digits while the subset C contains numeric data. This versatility of code 128 is the key to its wide scale use.


Computer Identics, in the year 1981, designed a barcode type denser than previously used code 39. The barcode type could encode all the 128 ASCII characters. It is for this reason this barcode type is called code 128.


The purpose of code 128 was to design such a barcode type which could encode large amounts of linear data in compact form. Previously, code 39 was used to code data but that barcode type was not suitable for encoding large amount of data due to its low density and in order to encode large data the length of the barcode had to be increased which was not a convenient solution. Hence researchers designed code 128 which was more dense and compact and could store large data.


Requires 6 elements to encode a character, 3 bars and 3 spaces which make it compact and concise storing large amount of data in small barcode unlike code 39 which required 9 elements to encode a character
Can encode all the ASCII characters (including all special characters) unlike code 39 which could encode only six special characters.
Provides more security over encoded data and minimized chances of error while scanning.


It has four different widths variation for each encoded character. It is not easy to print barcode with four different width variations per element.
More advanced scanning devices are required to scan these bar codes unlike code 39 which could be scanned with any general scanning device.
Like other linear barcodes (Code39, EAN13, EAN8, I2of5, UPCA, UPCE, Codabar, GS1 Databar, GS1 128), code 128 is also subjected to distortions and can be damaged easily.


Commonly used in shipping industry to identify containers and items.
Used in packaging and whole sale industry to identify and label variety of whole sale items.
Widely used in combination with code 39 in all the advanced brick and mortar companies.


If you want linear barcode with complete range of Alphabets, Numeric and ASCII characters, code 128 is the best option. It is compact, concise and can handle large amount of data.

Bytescout has two products which deal with Code 128.  ByteScout BarCode Generator is capable of generating Code 128 barcodes from your desktop and web applications and BarCode Reader SDK  reads Code 128 barcodes from scanned images, photo picutres and PDF files.