Andrés Fuster Guilló

Adjustable compression method for still JPEG images

There are a large number of image processing applications that work with different performance requirements and available resources. Recent advances in image compression focus on reducing image size and processing time, but offer no real-time solutions for providing time/quality flexibility of the resulting image, such as using them to transmit the image contents of web pages. In this paper we propose a method for encoding still images based on the JPEG standard that allows the compression/decompression time cost and image quality to be adjusted to the needs of each application and to the bandwidth conditions of the network. The real-time control is based on a collection of adjustable parameters relating both to aspects of implementation and to the hardware with which the algorithm is processed. The proposed encoding system is evaluated in terms of compression ratio, processing delay and quality of the compressed image when compared with the standard method. Our method performs real-time encoding/decoding still images based on JPEG standard.We introduce parameters that concern to the performance of the image processing.Adjusting the parameters affords to time/quality meet the application constraints.Experiments and quality test were made to probe the method consistency.

Image labelling in real conditions

Purpose – According to the problems of visual perception, we propose a model for the processing of vision in adverse situations of illumination, scale, etc. In this paper, a model for image segmentation and labelling obtained in real conditions with different scales is proposed.Design/methodology/approach – The model is based on the texture identification of the scenes objects by means of comparison with a database that stores series of each texture perceived with successive optic parameter values. As a basis for the model, self‐organising maps have been used in several phases of the labelling process.Findings – The model has been conceived to systematically deal with the different causes that make vision difficult and allows it to be applied in a wide range of real situations. The results show high success rates in the labelling of scenes captured in different scale conditions, using very simple describers, such as different histograms of textures.Research limitations/implications – Our interest is dire...

Architecture for image labelling in real conditions

A general model for the segmentation and labelling of acquired images in real conditions is proposed. These images could be obtained in adverse environmental conditions, such as faulty illumination, nonhomogeneous scale, etc. The system is based on surface identification of the objects in the scene using a database. This database stores features from series of each surface perceived with successive optical parameter values: the collection of each surface perceived at successive distances, and at successive illumination intensities, etc. We propose the use of non-specific descriptors, such as brightness histograms, which could be systematically used in a wide range of real situations and the simplification of database queries by obtaining context information. Self-organizing maps have been used as a basis for the architecture, in several phases of the process. Finally, we show an application of the architecture for labelling scenes obtained in different illumination conditions and an example of a deficiently illuminated outdoor scene.

Remote Web server of digital signal processors cards and its applications in education

A system is presented for the remote execution and planning of processes on digital signal processor cards. The hardware and software designed permits the sharing of processors and remote execution on the part of the users. We can distinguish three major modules: the Host, which acts as a signal processor hardware server; the customers, who send processes (typically programs written in C) and receive the compilation and results of the execution; and lastly, the host/customer connection (the link is carried out on a logic level, and thus independently of the type of net connection: Internet, Ethernet, token...). This situation is adequate for permitting access to high cost hardware platforms on the part of multiple users, facilitating the sharing of resources in research groups and the utilization in the classroom (at accessible costs) of high technology (where, until now, only the use of low cost processors has been envisaged).