Reversible Data Hiding with a New Local Contrast Enhancement Approach

Reversible data hiding schemes hide information into a digital image and simultaneously increase its contrast. The improvements of the different approaches aim to increase the capacity, contrast, and quality of the image. However, recent proposals contrast the image globally and lose local details since they use two common methodologies that may not contribute to obtaining better results. Firstly, to generate vacancies for hiding information, most schemes start with a preprocessing applied to the histogram that may introduce visual distortions and set the maximum hiding rate in advance. Secondly, just a few hiding ranges are selected in the histogram, which means that just limited contrast and capacity may be achieved. To solve these problems, in this paper, a novel approach without preprocessing performs an automatic selection of multiple hiding ranges into the histograms. The selection stage is based on an optimization process, and the iterative-based algorithm increases capacity at embedding execution. Results show that quality and capacity values overcome previous approaches. Additionally, visual results show how greyscale values are better differentiated in the image, revealing details globally and locally

Additional information delivery to image content via improved unseen–visible watermarking

In a practical watermark scenario, watermarks are used to provide auxiliary information; in this way, an analogous digital approach called unseen–visible watermark has been introduced to deliver auxiliary information. In this algorithm, the embedding stage takes advantage of the visible and invisible watermarking to embed an owner logotype or barcodes as watermarks; in the exhibition stage, the equipped functions of the display devices are used to reveal the watermark to the naked eyes, eliminating any watermark exhibition algorithm. In this paper, a watermark complement strategy for unseen–visible watermarking is proposed to improve the embedding stage, reducing the histogram distortion and the visual degradation of the watermarked image. The presented algorithm exhibits the following contributions: first, the algorithm can be applied to any class of images with large smooth regions of low or high intensity; second, a watermark complement strategy is introduced to reduce the visual degradation and histogram distortion of the watermarked image; and third, an embedding error measurement is proposed. Evaluation results show that the proposed strategy has high performance in comparison with other algorithms, providing a high visual quality of the exhibited watermark and preserving its robustness in terms of readability and imperceptibility against geometric and processing attacks

Variaciones climáticas en la Zona Metropolitana de la Ciudad de Toluca, Estado de México: 1960-2007

Los científicos del Panel Intergubernamental para el Cambio Climático (ipcc, 2001), han analizado las posibles consecuencias que pueden representar los cambios climáticos en distintos espacios geográficos de la Tierra. En México, el cambio climático empieza a ser notorio, por esta razón se realizó una investigación en la Zona Metropolitana de la Ciudad de Toluca y su hinterland para estudiar el comportamiento de la temperatura y la precipitación entre 1960 y 2007, y demostrar la existencia de variaciones que pueden contribuir al cambio climático. El sustento teórico de esta investigación fue la geografía ambiental, y el metodológico se basó en la estadística, trabajo de campo, el método comparativo y la cartografía automatizada. Con los resultados obtenidos se puede concluir que el clima en la zmct y su hinterland están en proceso de cambio y, de acuerdo con las investigaciones e informes de la nasa y el ipcc, éste seguirá cambiando globalmente.Los cientíÀcos del Panel Intergubernamental para el Cambio Climático (ipcc, 2001), han analizado las posibles consecuencias que pueden representar los cambios climáticos en distintos espacios geográÀcos de la Tierra. En México, el cambio climático empieza a ser notorio, por esta razón se realizó una investigación en la Zona Metropolitana de la Ciudad de Toluca y su hinterland para estudiar el comportamiento de la temperatura y la precipitación entre 1960 y 2007, y demostrar la existencia de variaciones que pueden contribuir al cambio climático. El sustento teórico de esta investigación fue la geografía ambiental, y el metodológico se basó en la estadística, trabajo de campo, el método comparativo y la cartografía automatizada. Con los resultados obtenidos se puede concluir que el clima en la zmct y su hinterland están en proceso de cambio y, de acuerdo con las investigaciones e informes de la nasa y el ipcc, éste seguirá cambiando globalmente

Avances en las técnicas de eliminación de marcas de agua visibles basadas en aprendizaje profundo

In recent years, artificial intelligence algorithms have shown great results in different application areas, such as robotics, medical, informatics security, financial services, among others. In the context of digital image processing, the use of deep learning is being applied to remove visible watermarks from the visual content of digital images, to remove the copyright protection of the owners of the images in question. This paper makes a briefly survey of the most recent works that remove visible watermarks employing deep learning, with the purpose of analyzing the current trends that allow designing more robust visible watermarking algorithms against this type of removal tools.En los últimos años los algoritmos de inteligencia artificial han demostrado tener grandes resultados en diferentes áreas de aplicación, tales como robótica, medicina, seguridad informática, finanzas, entre otras. En el contexto de procesamiento digital de imágenes, el uso del aprendizaje profundo está siendo aplicado para remover marcas de agua visibles en imágenes digitales, con la finalidad de eliminar la protección de derechos de autor de los propietarios de las imágenes en cuestión. El presente trabajo realiza una recopilación de los trabajos más recientes que remueven marcas de agua visibles a través de aprendizaje profundo, con la finalidad de analizar las tendencias actuales que permitan diseñar algoritmos de marcado de agua visible más robustos ante este tipo de herramientas de remoción

Tendencias y retos de la geografía en América Latina en el siglo XXI: una perspectiva desde el VII CGAL

Su estructura contempla siete capítulos: en el primero denominado Origen y devenir histórico del Coloquio Geográfico sobre América Latina de la Facultad de Geografía de la UAEM de los autores Carlos Reyes Torres, Agustín Olmos Cruz y Fernando Carreto Bernal, integrantes del Cuerpo Académico en Educación y Enseñanza de la Geografía, da cuenta del origen de los Coloquios Geográficos de AL, estableciendo sus etapas de desarrollo desde 1993 al 2014, caracterizando sus comités organizadores, ejes temáticos, así como la representación de los ponentes de las instituciones y países participantes. La relevancia de estos estudios radica en la recuperación de la historia de los eventos para fomentar la identidad y sentido de pertenencia con la disciplina y con la institución.El presente libro intitulado Tendencias y retos de la geografía en América Latina en el siglo XXI: una perspectiva desde el VII CGAL, es un producto derivado del 7° Coloquio Geográfico sobre América Latina, celebrado en desde hace ya dos décadas en la Facultad de Geografía de la Universidad Autónoma del Estado de México, convocando con el eje temático sobre “Las Tendencias y retos de la Geografía en América Latina en el siglo XXI”Universidad Autónoma del Estado de México Facultad de Geografí

Use of crowd logistics for the last mile of home parcel deliveries

Technology has transformed the way logistics is done and how parcels are delivered. Similarly, it has contributed towards an ascending e-commerce growth, making the shipping of goods more affordable, faster and more reliable. In consequence, this has created more demanding consumers with higher expectations including affordability, more control of the delivery process and faster deliveries. Along with consumers’ demands, the promptly increase of labor and fuel costs, the difficulty to fill drivers’ positions and the non-existent structure for urban deliveries with robot couriers has forced logistics companies to come up with innovative solutions to solve such problems being crowd logistics one of them. The objective of this research was to influence change in the traditional home parcel delivery process by leveraging new technologies such as crowd logistics to contribute to the creation of value for stakeholders around the home parcel delivery process. A mixed method was used to carry out the research where comparisons of variables such as cost, revenue generation, impact on the environment and flexibility for home parcel deliveries between crowd logistics and traditional delivery practices were made. The results indicate that the use of crowd logistics for home parcel deliveries can reduce costs directly and indirectly, it can increase the revenue for logistics companies and retailers, and most importantly, it could make the home parcel delivery process more resilient, giving consumers more control over the last mile. Furthermore, the use of crowd logistics did not have a positive impact on sustainability compared to traditional practices due to the heavy investment required from delivery couriers to switch to fossil free vehicles which could take years to accomplish. This research can serve as a guide for logistics companies in future projects concerning home parcel deliveries and therefore, contribute to a faster, flexible, and more profitable parcel business; however, generalizing the results and applying them to logistics companies in Finland of lower scale could be unsuitable due to external forces and inadequate infrastructure. It is recommended to continue with the research to have a more robust understanding about crowd logistics and leverage it for the creation of solutions

Imperceptible–Visible Watermarking to Information Security Tasks in Color Imaging

Digital image watermarking algorithms have been designed for intellectual property, copyright protection, medical data management, and other related fields; furthermore, in real-world applications such as official documents, banknotes, etc., they are used to deliver additional information about the documents’ authenticity. In this context, the imperceptible–visible watermarking (IVW) algorithm has been designed as a digital reproduction of the real-world watermarks. This paper presents a new improved IVW algorithm for copyright protection that can deliver additional information to the image content. The proposed algorithm is divided into two stages: in the embedding stage, a human visual system-based strategy is used to embed an owner logotype or a 2D quick response (QR) code as a watermark into a color image, maintaining a high watermark imperceptibility and low image-quality degradation. In the exhibition, a new histogram binarization function approach is introduced to exhibit any watermark with enough quality to be recognized or decoded by any application, which is focused on reading QR codes. The experimental results show that the proposed algorithm can embed one or more watermark patterns, maintaining the high imperceptibility and visual quality of the embedded and the exhibited watermark. The performance evaluation shows that the method overcomes several drawbacks reported in previous algorithms, including geometric and image processing attacks such as JPEG and JPEG2000

Complete Separable Reversible Data Hiding for Encrypted Digital Images Using Code Division Multiplexing with Versatile Bit Depth Management

A reversible data hiding in the encrypted domain (RDH-ED) aims to hide data within encrypted images, protecting its content, while allowing additional information to be distributed. This paper presents a complete separable RDH-ED scheme, whose main contribution is allowing the receiver to extract data and restore the image, either from the cryptogram with hidden data or from the directly decrypted version. With versatile bit-depth management, the most significant bits of each pixel are encrypted with AES-CTR cipher algorithm, while the additional data will be inserted inside the least significant bit planes of the encrypted pixels, by means of the code division multiplexing technique. Considering the marked/encrypted images, and encryption/data-hiding keys, a receiver could: (a) directly decrypt the encrypted image and obtain its approximate version, (b) extract the error-free hidden data, and (c) recover the data and original image. Considering an image approximation version and the data hiding key, a receiver could: (d) extract the hidden data from the plaintext domain, and (e) restore the image to its original state, while accessing the hidden data without any loss. Experimental results show the performance of the developed algorithm, evaluating the capacity and imperceptibility of the proposed scheme with respect to current state of the art