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Digital Image Processing Tutorial- Introduction to Erdas Imagine Software

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Introduction to ERDAS IMAGINE Software There are several image processing software available in paid and free source categories. Erdas Imagine is very commonly used image processing software. In this article, sharing how to start with Erdas Imagine software. ERDAS imagine is image processing software supported by Leica Geosystems Inc earlier but now Hexagon Geospatial providing this software.  ERDAS Imagine is raster based software that is specifically designed for information extraction from satellite images . The functions embedded involve importing, viewing, altering and analyzing both raster and vector data sets. This software is capable of handling an unlimited number of bands of image data in a single file.  These bands imported into ERDAS IMAGINE are often treated as layers. Additional layers can be created and added to existing image file. It allows users to import a wide variety of remotely sensed imagery from satellite and aerial platforms. In this article ERDAS Imagin

Digital Image Processing Tutorial-- Layer Stacking and Subset a Satellite Image

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Satellite Image Processing Satellite image processing include various steps and processes to make image ready for interpretation and classification . These processes are important on each step of image processing such as geometric correction, radiometric correction, enhancement , classification etc.  These processing methods are also depend on number of bands present in image as well as on spatial and temporal properties of satellite image . In this article some basic image processing tools are discussed using  Erdas Imagine. As data downloaded/purchased than there may be some basic operations need to perform for digital image processing . These tools may vary with data acquired, in general satellite data need to stack, subset, mosaic and re-project based on the project requirement and data availability. Layer Stacking: This process is primary process after acquiring satellite images as most of the satellite images are provided in different bands or layers , such a

Digital Image Processing Tutorial- How to Enhance Satellite Image Enhancement Part-II

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Image Enhancement Part-II (Spatial, Spectral and Radiometric Enhancement) There are several others methods to improve quality of image for better interpretation . These enhancement methods are divided on the basis of three basic image concepts of spatial resolution, spectral resolution and radiometric resolution . Therefore they called as spatial enhancement, spectral enhancement and radiometric enhancement. Spatial Enhancement  As it called spatial enhancement so it enhances spatial resolution properties of a satellite image . Spatial resolution defined as ability of sensor to distinguish the small objects. It refers to the amount of detail that can be detected by a sensor. Image pixel size defines the spatial resolution of a satellite image.  For detailed mapping of land use practices requires a much greater spatial resolution. If enhance the spatial properties of image to get more detailed and accurate information one should use this spatial enhancement tool.  This

Digital Image Processing- Introduction of Satellite Images

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Digital Image Processing of a Satellite Image For image processing , need satellite images , which is also called digital Image/data. Introduction to Digital Image/Data (Satellite Image) Introduction An image is an array, or a matrix, of square pixels (picture elements) arranged in columns and rows. Digital images consist of discrete picture elements called PIXELS. A number is associated with each pixel represented as DN (Digital Number). DN depicts by positive numbers, which have the average of electromagnetic energy captured by satellite sensors. The pixel size is reduced more scene detail is preserved in digital representation. The digital numbers are in the form of 'bits' which vary from 0 to a selected power of 2. Such as if a 8 bit data then it becomes 28 and represent 256 variance recorded by sensor of reflected radiance from object. There are two type of satellite image Black and White, which is also called panchromatic image. Color composite, which can be displayed

Digital Image Processing Tutorial-Image Enhancement Part-I

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Image Enhancement-Contrast Adjustment In the last article, learned about the basis concepts of image enhancement and importance of enhancement in satellite image processing .  Understand satellite image , especially DN values stores in each pixel  Process in Erdas Imagine to see DN values stored in pixels through viewer Image Info.  Adjustment of contrast of Image to improve quality  Image Enhancement Processes  In this article will move further to understand some more process can be used to improve quality of image. But this needs basic understanding of DN value and its range for all bands used in image stacking .   There are some enhancement process are available in all image processing software . Here will discuss enhancement functions of Erdas Imagine software .   After displaying a satellite image in viewer of Erdas,   click on Raster tool from menu bar of Viewer.  Click on Contrast  There Select General contrast   in that tool many contrast adjustme