Digital Image Processing

Fluorescence is the property where certain security features on currency notes glow when exposed to ultraviolet (UV) light. The number panels on banknotes are treated with fluorescent ink that becomes visible only under UV light, making counterfeiting much more difficult. Latent image requires tilting, watermark is visible against normal light, and back-to-back registration involves design alignment.

A pixel (short for 'picture element') is the smallest unit of a digital image. It is a single point in a raster image and represents the minimum addressable element of a display screen.

FITS stands for Flexible Image Transport System, which is the standard data format used in astronomy for storing images and data. It's designed for scientific imaging and can handle multidimensional data arrays.

In black and white photography, filters lighten their own color and darken complementary colors. A red filter allows red light to pass through freely, so red objects appear lighter in the final print. Green and blue objects appear darker because those colors are absorbed.

Bitmap checkpoints in QTP/UFT capture and compare screen areas pixel-by-pixel. Screen resolution changes affect pixel density and layout, while image size determines the captured area dimensions. Object type doesn't matter for bitmap comparisons since they're purely visual - it's all about screen pixels. Image type vs object type distinctions aren't relevant to bitmap checkpoint sensitivity.

The 1x1 transparent GIF spacer technique was a common web design workaround before CSS became standard. Hspace and Vspace were deprecated HTML attributes for image spacing. Using a tiny transparent image stretched to desired size was the preferred alternative. Width/height define the image dimensions, not spacing around it.

dip stands for density-independent pixel. It's an abstract unit that scales based on screen density - 1 dip equals 1 pixel on a 160 dpi screen. This ensures UI elements appear the same physical size across different devices.

Bitonal TIFF is preferred for scanned documents because it supports black-and-white imaging (sufficient for most business documents), uses lossless compression (preserves exact document content), and can store multi-page documents in a single file (efficient for archival). These combined benefits make it ideal for enterprise document management.

This method is used in image processing of applet to modify the work_pixels array for the next cell.

Convolution is a simple mathematical operation which is fundamental to many common image processing operators. Convolution provides a way of 'multiplying together' two arrays of numbers, generally of different sizes, but of the same dimensionality, to produce a third array of numbers of the same dimensionality.

Halftone is the reprographic technique that simulates continuous tone imagery through the use of dots, varying either in size, shape or spacing.

Images that gradually appear sharper are called interlaced graphics.

The Histogram shows the total tonal distribution in the image. It's a barchart of the count of pixels of every tone of gray that occurs in the image. It helps us analyze, and more importantly, correct the contrast of the image.