When digitizing documents, we may accidentally scan a document image twice. Finding the duplicate images manually is painstaking. In this article, we are going to use JavaScript to detect duplicate document images automatically. How to Calculate the Similarity between Two Images We need to compare two images to check whether...

Object detection is a computer technology related to computer vision and image processing that deals with detecting instances of semantic objects of a certain class (such as humans, buildings, or cars) in digital images and videos.1 It can be used in a barcode reading task as barcodes are often printed...

Filters are commonly used to adjust the rendering of images. We can use it to make images sharper, remove unwanted objects, or adjust the color tone. In this article, we are going to build a JavaScript library to perform various image filters. It can be used together with Dynamsoft Document...

Whether we scan documents via document scanners or cameras, we may end up getting document images with bad quality. In this article, we are going to talk about how to evaluate the quality of scanned document images so that we can recapture the document to get a better image. A...

A black-and-white binary image consists of pixels that can have one of exactly two colors: black and white. Converting an image to black and white has some usages: File size reduction: a 1-bit binary image requires less data for storage than a 24-bit color image. Image processing: many image processing...

Grayscale images are composed exclusively of shades of gray. They are commonly stored with 8 bits per sampled pixel, which allows 256 different intensities to be recorded. Converting an image to grayscale has some usages: File size reduction: an 8-bit grayscale image often requires less data for storage than a...

Sometimes, we may need to flip a media element in a web app. For example, we may need to flip a video element streaming from a camera to match what we actually see or correct scanned document images that are flipped. In this article, we are going to talk about...

In a document-scanning web app, image resizing is useful as it can correct the proportion of scanned documents and increase the DPI of document images to meet printing requirements. In this article, we are going to talk about how to resize an image with JavaScript. One way is using Canvas...

Sometimes, we may need to rotate an image on a web page, like showing a loading animation. In a document-scanning web app, we need to rotate skewed document images or document images scanned in the wrong direction. In this article, we are going to talk about three ways to rotate...

Scanning documents into a digital form can help companies save physical space, improve data retrieval, reduce costs, improve collaboration, etc. Sometimes, we may come across very large scanned document files or files scanned with a low visual quality. In this article, we are going to talk about aspects related to...

Scanned documents often contain skewed or crooked images. They do not look good and are not friendly for OCR. In this article, we are going to use OpenCV and Python to deskew scanned documents based on text lines. Steps to Deskew a Scanned Document Image with OpenCV We are going...

Motion detection can detect whether there is a change in the positions of objects. It can be achieved by many methods. For example, infrared light or laser technology can be used for optical detection. As for image processing methods, there is a basic one by a fixed camera, which compares...

We need to use OCR in various scenarios, whether we want to scan the credit card number with our phone or extract text from documents. Dynamsoft Label Recognition (DLR) and Dynamic Web TWAIN (DWT) have the OCR ability to accurately read text. Although generally they can do a good job,...

In reality, we can always see some photos that have low brightnesses and low contrast. To make objects recognizable in pictures,  we need to process the photo with Illumination Compensation. There are many algorithms used for Illumination Compensation such as Histogram equalization, Color similarity measure, Gamma Correction and so on. In this tutorial, I...