Digital Images

The concentration of people in densely populated urban areas, especially in developing countries, calls for the use of monitoring systems like remote sensing. Such systems along with spatial analysis techniques like digital image processing and geographical information system (GIS) can be used for the monitoring and planning purposes as these enable the reporting of overall sprawl at a detailed level.In the present work, urban sprawl of the Ajmer city (situated in Rajasthan State of India) has been studied at a mid scale level, over a period of 25 years (1977–2002), to extract the information related to sprawl, area of impervious surfaces and their spatial and temporal variability. Statistical classification approaches have been used for the classification of the remotely sensed images obtained from various sensors viz. Landsat MSS, TM, ETM+ and IRS LISS-III. Urban sprawl and its spatial and temporal characteristics have been derived from the classified satellite images. The Shannon's entropy and landscape metrics (patchiness and map density) have been computed in terms of spatial phenomenon, in order to quantify the urban form (impervious area). Further, multivariate statistical techniques have been used to establish the relationship between the urban sprawl and its causative factors. Results reveal that land development (160.8%) in Ajmer is more than three times the population growth (50.1%). Shannon's entropy and landscape metrics has revealed the spatial distribution of the urban sprawl over a period of last 25 years.

A digital watermark is an invisible mark embedded in a digital image which may be used for Copyright Protection. This paper proposes that Fourier-Mellin transform-based invariants can be used for digital image watermarking. The embedded marks may be designed to be una ected by any combination of rotation, scale and translation transformations. The original image is not required for extracting the embedded

– In this paper, we will provide an overview of the mechanisms used in image protection, especially Chaos-based encryption techniques available today. We will see how previously proposed methods such as Data Encryption Standard (DES), Triple Data ...

In the latter half of the 1990s the digital
image became prevalent, easy to manipulate, and consequently, easy to recontextualize,
meaning that now just about any image is available to any computer user for any occasion. To use Bolter's terminology, the "interpenetration" of textual and pictorial space in digital environments, especially on the Web, has increased
markedly, so that the predominance of the digital image now rivals that of the digital word. Indeed, a number of thinkers have noted the digital image's ascendancy in communicating
information via the computer. But how are we to think about, to analyze the rhetorical dimensions of these images? This essay focuses on using classical rhetoric 'as a way of
thinking about the persuasive power of computer-based images.

This article traces the trajectory of the Hindu nationalist imagination of the Kaaba in Mecca as an ancient Shiva temple. It argues that, though the narrative is old, it was the transition from text to digital images that resulted in violent offence controversies in India and Bangladesh. The entire book is Open Access at
https://www.uclpress.co.uk/products/123481

The Least Significant Bit (LSB) algorithm and the Most Significant Bit (MSB) algorithm are steganography algorithms with each one having its demerits. This work therefore proposed a Hybrid approach and compared its efficiency with LSB and MSB algorithms. The Least Significant Bit (LSB) and Most Significant Bit (MSB) techniques were combined in the proposed algorithm. Two bits (the least significant bit and the most significant bit) of the cover images were replaced with a secret message. Comparisons were made based on Mean-Squared Error (MSE), Peak Signal-to-Noise Ratio (PSNR) and the encoding time between the proposed algorithm, LSB and MSB after embedding in digital images. The combined
technique produced a stego-image with minimal distortion in image quality than MSB technique independent of the nature of data that was hidden. However, LSB algorithm produced the best stego-image quality. Large cover images however made the combined algorithm’s quality better improved. The
combined algorithm had lesser time of image and text encoding. Therefore, a trade-off exists between the encoding time and the quality of stego-image as demonstrated in this work.

Noise is always presents in digital images during image acquisition, coding, transmission, and processing steps. Noise is very difficult to remove it from the digital images without the prior knowledge of noise model. That is why, review of noise models are essential in the study of image denoising techniques. In this paper, we express a brief overview of various noise models. These noise models can be selected by analysis of their origin. In this way, we present a complete and quantitative analysis of noise models available in digital images.

Signal & Image Processing : An International Journal is an Open Access peer-reviewed journal intended for researchers from academia and industry, who are active in the multidisciplinary field of signal & image processing. The scope of the journal covers all theoretical and practical aspects of the Digital Signal Processing & Image processing, from basic research to development of application.

For various reasons, aerial archaeologists use(d) film when studying their objects in the Near InfraRed (NIR). However, even the use of colour InfraRed (CIR) emulsions remained severely restricted till today due to some ignorance or a severe lack of knowledge about the subject and – not at least – the critical imaging process. This error-prone film-based workflow belongs now to the past, thanks to the advent of digital cameras. In this article, two new approaches will be outlined, both in an attempt to overcome the constraints on the common archaeological interpretation of varying visible colours in vegetation: the use of modified hand-held digital cameras to photograph the NIR spectrum on the one hand, as well as future plans to digitally capture both Red and NIR wavelengths simultaneously on the other. Besides additional technical background information on NIR photography, the paper treats the advantages (and disadvantages) of NIR to normal archaeological aerial imaging. In the end, an introduction of a new, remotely controlled system to support (aerial) archaeologists in their (NIR) photography is given together with several approaches to NIR image processing.

Thispersondoesnotexist.com offers a refreshable, seductively realistic, series of images of exactly that: a steady supply of amalgamated images of fictional people. Built from an unknown number of Flickr photographs gleaned from the open archives of the internet, these photographically hyper-realistic images enjoy the appearance of veristic "truth," yet are framed by their status as synthetic products generated by Artificial Intelligence, or A.I. Like other images generated using A. I. algorithms (General Adversarial Networks, or GANs), thispersondoesnotexist is known as a "DeepFake" generator. Thispersondoesnotexist, its spinoffs (thisAirBnBdoesnotexist, thesecatsdonotexist, thiswaifudoesnotexist.net, and thisstartupdoesnotexist), FakeApp, DeepFaceLab, DeepDream, Lyrebird, AIMonaLisa, DeepNude, and a proliferation of others, create images and videos so seemingly realistic usingan archive of materials that they hardly – if at all – can be distinguished from actua...