Modern technology and computer science is spreading and developing very fast. The use and facilities evolve too. One of the fields where computer science is widely used – computer games. Computer animation makes games more interactive and attractive to the user. The purpose of this project was to review and analyze the animation techniques used in modern games development. Review file formats witch are used in computer games to store game objects and animation data. Try to point out the strengths and weaknesses of animation techniques. Main attention was committed to skeletal and key frame animation. Implement skeletal and key frame animation techniques.

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[EN] This Thesis presents a set of tools that allows the improvement of the digital video coding efficiency by exploiting the fundamentals of the state of the art video coding standards. This work has been focused both on research and on the application of the results to the encoding of digital video in real time mobile environments. The first contribution is an automatic shot change detection algorithm integrated in the encoding process. This algorithm is based on the monitoring of the coding mode of the macroblocks of the sequence, and the proper definition of a set of parameters provides excellent detection rates, precision and recall. The results also indicate an improvement on the encoded video quality when these detection techniques are used, which triggers the definition of a content-based keyframe selection algorithm. With this method, the optimal position of reference pictures can be determined. These keyframes are then used by the encoder to perform temporal prediction of the subsequent frames, which improves the compression rate and the encoded video quality (both objective and subjective). This quality improvement is the main objective of this Thesis. In the last part of this work, a rate control algorithm for variable bitrate and frame rate environments has been defined, being able to generate a bitstream that quickly follows the varying conditions of the mobile channel. In parallel to all this work, a set of training and test sequences has been obtained, providing an optimal environment for the design, development, configuration, optimization and test of the algorithms described here. / [ES] Esta tesis presenta un conjunto de herramientas que permiten mejorar la eficiencia de codificación de vídeo mediante la explotación de los fundamentos en los que se basan los principales estándares de codificación actuales. El trabajo se ha orientado tanto a la investigación como a la aplicación de los resultados a la codificación de vídeo en tiempo real en entornos móviles. En primer lugar se ha definido un algoritmo de detección automática de cambios de plano para entornos de tiempo real integrado en el proceso de codificación. Este algoritmo está basado en la monitorización del modo de codificación de los macrobloques de la secuencia y la correcta definición de un conjunto de parámetros consigue unas tasas de detección, una precisión y una eficacia superiores a otros métodos similares existentes en la literatura. Los resultados muestran también una mejora en la calidad del vídeo codificado al aplicar estas técnicas de detección, lo que lleva a la definición de un algoritmo de selección de imágenes de referencia (keyframes) basado en el contenido. Así se pueden obtener las posiciones óptimas para las imágenes de referencia utilizadas por el codificador para realizar predicciones temporales que aumentan la calidad tanto objetiva como subjetiva del vídeo codificado, lo que constituye a su vez el objetivo principal de esta tesis. Por último, se ha diseñado un algoritmo de control de tasa capaz de obtener un bitstream que se adapta rápidamente a los cambios tanto de bitrate como de tasa de imágenes por segundo producidos en el canal móvil. Paralelamente, se ha obtenido un conjunto de secuencias de entrenamiento y test que proporcionan un entorno óptimo para el diseño, desarrollo, configuración, optimización y prueba de los algoritmos aquí descritos. / [CAT] Aquesta tesi presenta un conjunt de ferramentes que permeten millorar la eficiència de codificació de vídeo digital mitjançant l'explotació dels fonaments en els que es basen els principals estàndards de codificació actuals. El treball ha estat orientat tant a la investigació com a l'aplicació dels resultats a la codificació de vídeo en temps real en entorns mòbils. En primer lloc s'ha definit un algoritme de detecció automàtica de canvis de plànol integrat en el propi procés de codificació. Aquest algoritme s'ha basat en la monitorització del mode de codificació dels macroblocs de la seqüència, i la correcta definició d'un conjunt de paràmetres de configuració permet aconseguir unes taxes de detecció, una precisió i una eficàcia superiors a altres mètodes similars presents a la literatura. Aquests resultats també indiquen una millora en la qualitat del vídeo codificat al aplicar aquestes tècniques de detecció la qual ens porta a la definició d'un algoritme de selecció d'imatges de referència (keyframes) basada en el contingut. Amb aquest algoritme es poden obtenir les posicions òptimes per a les imatges de referència utilitzades pel codificador per a realitzar prediccions temporals òptimes que augmenten la qualitat tant objectiva com subjectiva del vídeo codificat. Amb esta millora s'assoleix l'objectiu principal d'aquesta tesi. Per últim, s'ha dissenyat un algoritme de control de taxa capaç d'obtenir un bitstream que s'adapta ràpidament als canvis tant de bitrate com de taxa d'imatges per segon requerits per les condicions canviants del canal mòbil. Paral·lelament s'ha obtingut un conjunt de seqüències d'entrenament i test que permet disposar d'un entorn òptim per al disseny, desenvolupament, configuració, optimització i prova dels algoritmes descrits en aquestes fulles. / Usach Molina, P. (2015). TÉCNICAS DE MEJORA DE LA EFICIENCIA DE CODIFICACIÓN DE VÍDEO [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59446 / TESIS

The main goal of this project was to familiarize readers with the techniques used in real-time animation of 3D characters. This work is focused on two types of animation: keyframe animation and skeletal animation. There are described algorithms for software and hardware accelerated model deformations, keyframe interpolations, animation blending, inverse kinematics and ragdoll. The result of this project is a framework, which consists of an animation library, examples demonstrating library functions and tools for export animations from 3D Studio Max and MilkShape 3D.

Simulating realistic human behavior on a virtual avatar presents a difficult task. Because the simulated environment does not adhere to the same scientific principles that we do in the existent world, the avatar becomes capable of achieving infeasible postures. In an attempt to obtain realistic human simulation, real world constraints are imposed onto the non-sentient being. One such constraint, and the topic of this thesis, is self-collision avoidance. For the purposes of this topic, a posture will be defined solely as a collection of angles formed by each joint on the avatar. The goal of self-collision avoidance is to eliminate the formation of any posture where multiple body parts are attempting to occupy the exact same space. My work necessitates an extension of this definition to also include collision avoidance with objects attached to the body, such as a backpack or armor. In order to prevent these collisions from occurring, I have implemented an effort-based approach for correcting afflicted postures. This technique specifically pertains to postures that are sequenced together with the objective of animating the avatar. As such, the animation's coherence and defining characteristics must be preserved. My approach to this problem is unique in that it strategically blends the concept of keyframe interpolation with an optimization-based strategy for posture prediction. Although there has been considerable work done with methods for keyframe interpolation, there has been minimal progress towards integrating a realistic collision response strategy. Additionally, I will test this optimization-based approach through the use of a complex kinematic human model and investigate the use of the results as input to an existing dynamic motion prediction system.

Στην παρούσα εργασία υλοποιούμε ένα σύστημα δημιουργίας περιλήψεων από ακολουθίες βίντεο. Υλοποιούνται όλα τα βήματα που θα πρέπει να ακολουθηθούν (εξαγωγή χαρακτηριστικών-ανίχνευση πλάνων-εξαγωγή χαρακτηριστικών καρέ) έτσι ώστε να εξαχθεί ένα σύνολο καρέ (χαρακτηριστικά καρέ) τα οποία να συνοψίζουν νοηματικά το περιεχόμενο μιας ακολουθίας βίντεο. Η επεξεργασία του βίντεο γίνεται απευθείας στο συμπιεσμένο πεδίο και συγκεκριμένα σε συμπιεσμένα αρχεία MPEG-1-2, έτσι ώστε τα αποτελέσματα να εξάγονται σε σχετικά μικρό χρόνο και με σχετικά χαμηλές απαιτήσεις σε αποθηκευτικό χώρο και επεξεργαστική ισχύ. / In this paper a video summarization system is being constructed. We acomplish all the needed steps (feature extraction -shot detection-keyframe extraction) in order to extract a set of frames (keyframes) that capture the semantic content of the video sequence. The processing of the video takes place directly at the compressed domain (at MPEG-1-2 video files). Thus we obtain results at relatively little time and with relatively low storage and computer power demands.

Dans ce travail, nous proposons une représentation efficace de l’environnement adaptée à la problématique de la navigation autonome. Cette représentation topométrique est constituée d’un graphe de sphères de vision augmentées d’informations de profondeur. Localement la sphère de vision augmentée constitue une représentation égocentrée complète de l’environnement proche. Le graphe de sphères permet de couvrir un environnement de grande taille et d’en assurer la représentation. Les "poses" à 6 degrés de liberté calculées entre sphères sont facilement exploitables par des tâches de navigation en temps réel. Dans cette thèse, les problématiques suivantes ont été considérées : Comment intégrer des informations géométriques et photométriques dans une approche d’odométrie visuelle robuste ; comment déterminer le nombre et le placement des sphères augmentées pour représenter un environnement de façon complète ; comment modéliser les incertitudes pour fusionner les observations dans le but d’augmenter la précision de la représentation ; comment utiliser des cartes de saillances pour augmenter la précision et la stabilité du processus d’odométrie visuelle. / Our aim is concentrated around building ego-centric topometric maps represented as a graph of keyframe nodes which can be efficiently used by autonomous agents. The keyframe nodes which combines a spherical image and a depth map (augmented visual sphere) synthesises information collected in a local area of space by an embedded acquisition system. The representation of the global environment consists of a collection of augmented visual spheres that provide the necessary coverage of an operational area. A "pose" graph that links these spheres together in six degrees of freedom, also defines the domain potentially exploitable for navigation tasks in real time. As part of this research, an approach to map-based representation has been proposed by considering the following issues : how to robustly apply visual odometry by making the most of both photometric and ; geometric information available from our augmented spherical database ; how to determine the quantity and optimal placement of these augmented spheres to cover an environment completely ; how tomodel sensor uncertainties and update the dense infomation of the augmented spheres ; how to compactly represent the information contained in the augmented sphere to ensure robustness, accuracy and stability along an explored trajectory by making use of saliency maps.

The goal of this work is to create an application, which will combine procedural and keyfram animations with subsequent visualization. Composition of this two different animations techniques is used to animate a virtual character. To combine this two techniques one starts with interpolations from keyframe animation and then enchance them by procedural animations to properly fit into the characters surroundings. This procedural part of animation is obtained by using forward and inverse kinematics. Whole application is written in C++, uses GLM math library for computations and OpenGL and GLUT for final visualization.

This thesis proposes an architecture of animation engine flexible enough to support large scale of animation algorithms with unified approach to each one of them. One of the major goals of the engine is to support creation of very complex animation seqences with high degree of animation execution control. The main animation technique used in the engine is skeletal animation and some variants of this technique are already implemented within, but it was never meant to be skeletal animation only engine and is designed that way.