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It is well-known that there has been a considerable progress in multimedia technologies during the last decades, namely TV, photography, sound and video recording, communication systems, etc., which came into the world during at least half of the previous century and were developed as analog systems, and nowadays have been almost completely replaced by digital systems. The aforementioned motivates a deep study of multimedia compression and intensive research in this area. Data compression is concerned with minimization of the number of information carrying units used to represent a given data set. Such smaller representation can be achieved by applying coding algorithms. Coding algorithms can be either lossless algorithms that reconstruct the original data set perfectly or lossy algorithms that reconstruct a close representation of the original data set. Both methods can be used together to achieve higher compression ratios. Lossless compression methods can either exploit statistical structure of the data or compress the data by building a dictionary that uses fewer symbols for each string that appears on the data set. Lossy compression, on the other hand, uses a mathematical transform that projects the current data set onto the frequency domain. The coefficients obtained from the transform are quantized and stored. The quantized coefficients require less space to be stored. This chapter is focused on the recently published advances in image and video compression to date considering the use of the integer discrete cosine transform (IDCT), wavelet transforms, and fovea centralis.

Quick Response QR barcode detection in nonarbitrary environment is still a challenging task despite many existing applications for finding 2D symbols. The main disadvantage of recent applications for QR code detection is a low performance for rotated and distorted single or multiple symbols in images with variable illumination and presence of noise. In this paper, a particular solution for QR code detection in uncontrolled environments is presented. The proposal consists in recognizing geometrical features of QR code using a binary large object- (BLOB-) based algorithm with subsequent iterative filtering QR symbol position detection patterns that do not require complex processing and training of classifiers frequently used for these purposes. The high precision and speed are achieved by adaptive threshold binarization of integral images. In contrast to well-known scanners, which fail to detect QR code with medium to strong blurring, significant nonuniform illumination, considerable symbol deformations, and noising, the proposed technique provides high recognition rate of 80%–100% with a speed compatible to real-time applications. In particular, speed varies from 200 ms to 800 ms per single or multiple QR code detected simultaneously in images with resolution from 640 × 480 to 4080 × 2720, respectively.

Wavelet foveated compression can be used in real-time video processing frameworks for reducing the communication overhead while keeping high visual quality. Such algorithm leads into high rate compression results due to the fact that the information loss is isolated outside a region of interest (ROI). The fovea compression can also be applied to other classic transforms such as the commonly used the discrete cosine transform (DCT). In this paper, a fovea window for wavelet-based compression is proposed. The proposed window allows isolate a fovea region over an image. A comparative analysis has been performed showing different error and compression rates between the proposed fovea window for wavelet-based and the DCT-based compression algorithms. Simulation results show that with foveated compression high ratio of compression can be achieved while keeping high quality over the designed ROI.

Wavelet foveated compression can be used in real-time video processing frameworks for reducing the communication overhead. However, each wavelet can yields into different results on compression ratio. Classic foveation filters also applies cutoff frequencies over the region of interest (ROI). A comparative analysis has then been performed showing the different error rate for different cutoff frequency windows that preserves the ROI coefficients intact against windows that apply cutoffs over the ROI. Simulation results show that with wavelet-based foveated compression high ratio of compression can be achieved while keeping high quality over the designed ROI.