Low-resolution images can come from a variety of sources, but the most common source is probably screen capture. Screen capture images are usually 96 DPI on Windows. (This can vary depending on the user settings). Additionally, image representations of incoming faxes may also be considered low-res and fall under the resolution threshold acceptable for OCR. Typically, OCR engines require images of 200 or 300 DPI in order to achieve acceptable results.

Change Image Resolution

One easy solution for images that do not have noise or have complex structures is to change the resolution of the image before OCRing the image. This C# sample shows you how, then it gets the text from the image and outputs it to the console.

Even today there are many organizations that rely on fax as a required form of communications. Because of this, receiving faxes is a requirement that much still be met. To do this, many organizations utilize fax services either hosted locally or by a third-party. Many of these services will email received faxes to users as a PDF file.

In a normal facsimile transmission, every other scan-line is skipped. This reduces the amount of data that needs to be sent over the relatively slow connection used to send faxes. To account for the missing scan-lines, the aspect ratio of the pixels is 2:1. It is important to recognize this when displaying the image else you will end up displaying the image incorrectly, making it looked squashed.

When LEAD Technologies set out to create its HTML5 SDK, we wanted to do it right by making LEADTOOLS the fastest and most interactive toolkit available. Thanks to our many customers investing in and developing with this technology, we take that as a vote of confidence that we have succeeded in attaining that goal.

There are many ways to design a zero footprint application, and unfortunately the performance and quality often suffer due to many applications simply pushing all of the image processing to a server. With the LEADTOOLS JavaScript libraries, you can gain all the advantages of zero footprint development without losing the user-friendliness of an application that can provide instantaneous visual feedback.

As part of the LEAD Technologies 25th anniversary, we are creating 25 projects in 25 days to celebrate LEAD's depth of features and ease of use. Today's project comes from Faris.

What it Does

This project will perform various image cleanup functions until a barcode is recognized using LEADTOOLS Version 19. To run the project, extract it to the C:\LEADTOOLS 19\Examples\DotNet\CS directory.

As I mentioned in my previous post, Correct Photos of Documents – Ambient Lighting, most images of documents suffer from skew. There are two types of skew: two-dimensional and three-dimensional.

Text is typically parallel to the top and bottom of the paper. Simply put, two-dimensional skew is the angle of the text when compared to the top or bottom edge of the image. This type of skewing can occur in photos of documents as well as document images produced by a scanner. While it is relatively easy to correct with a simple rotate, determining the angle of rotation can be tricky. Fortunately, LEADTOOLS includes a DeskewCommand class that can determine the angle of skew.