On-the-fly Historical Handwritten Text Annotation

The performance of information retrieval algorithms depends upon the availability of ground truth labels annotated by experts. This is an important prerequisite, and difficulties arise when the annotated ground truth labels are incorrect or incomplete due to high levels of degradation. To address this problem, this paper presents a simple method to perform on-the-fly annotation of degraded historical handwritten text in ancient manuscripts. The proposed method aims at quick generation of ground truth and correction of inaccurate annotations such that the bounding box perfectly encapsulates the word, and contains no added noise from the background or surroundings. This method will potentially be of help to historians and researchers in generating and correcting word labels in a document dynamically. The effectiveness of the annotation method is empirically evaluated on an archival manuscript collection from well-known publicly available datasets

Learning Surrogate Models of Document Image Quality Metrics for Automated Document Image Processing

Computation of document image quality metrics often depends upon the availability of a ground truth image corresponding to the document. This limits the applicability of quality metrics in applications such as hyperparameter optimization of image processing algorithms that operate on-the-fly on unseen documents. This work proposes the use of surrogate models to learn the behavior of a given document quality metric on existing datasets where ground truth images are available. The trained surrogate model can later be used to predict the metric value on previously unseen document images without requiring access to ground truth images. The surrogate model is empirically evaluated on the Document Image Binarization Competition (DIBCO) and the Handwritten Document Image Binarization Competition (H-DIBCO) datasets

Stereo Visualisation of Historical Aerial Photos - a Valuable Digital Heritage Research Tool

We demonstrate with several examples how historical aerial photos can benefit from being viewed in stereo and how this can be useful as tool in digital heritage research. The main reason why stereo images are important is that they give a much better understanding of what is actually in the scene than single photos can. The important factor is the depth cue that helps understanding the content and adds the ability to distinguish between objects such as houses and trees and the ground as well as estimating heights of objects. There are however still challenges but also possibilities that will be discussed

Optimal Robot Control using Modelica and Optimica

In this paper, Modelica along with Optimica has been used to formulate and solve a minimum time optimization problem. The problem concerns traversing a given path with a robot in as short time possible under input constraints. Different problem reformulations are discussed that increase the chance of finding optimal solutions. This paper also discusses the use of these optimal solutions for control of industrial robots. A control structure, in which the optimal trajectories are essential, are used on an ABB IRB140B to ensure robustness for model errors and disturbances

Automatic 3DS Conversion of Historical Aerial Photographs

In this paper we present a method for the generation of 3D stereo (3DS) pairs from sequences of historical aerial photographs. The goal of our work is to provide a stereoscopic display when the existing exposures are in a monocular sequence. Each input image is processed using its neighbours and a synthetic image is rendered, which, together with the original one, form a stereo pair. Promising results on real images taken from a historical photo archive are shown, that corroborate the viability of generating 3DS data from monocular footage

Efficient Methods for Fast Shading

On devices without battery consuming and specialized hardware for rendering, it is important to improve the speed and quality so that these methods are suitable for real-time rendering. Furthermore such algorithms are needed on the coming multicore architectures. We show how the methods by Gouraud and Phong, the commonly most used methods for shading, can be improved and made faster for both software rendering as well as simple low energy consuming hardware implementations. Moreover, this paper summarizes the authors’ achievements in increasing shading speed and performance and a Bidirectional Reflectance Distribution Function is simplified for faster computing and hardware implementatio

Models that use logarithmic and power functons

Nowadays, a tremendous speed of computer technologies is being observed. This caused intensive numerous researches in the fields of data protection, information processing and image processing. This article is devoted to computer graphics. To create and manipulate realistic objects in computer graphics one needs to have powerful computers to perform a lot of complicated computations. Though, GPU in modern visual adapters is able to handle very complicated operations during short period of time, a lot of other devices (e.g. hand-held devices) not equipped with GPU require simplification of computations for image shading. Herein we suggest approximation of BRDF (Bidirectional Reflectance Distribution Function) which hard to get computed, by two quadratic polynomials

Topology maps for anisotropic shading

There are a number of materials, like cloth, hair and brushed metal that exhibit anisotropic reflectance properties. Several illumination models have been proposed for shading of such materials. The model by Poulin and Fournier describes how hair, silk and material which can be modeled by parallel cylinders, can be rendered. It has been proposed recently how the topology for this model can vary over the surface as would be the case for many surfaces like spheres and toruses. In this paper it is described how the shading can be visually enhanced by using a map for the topology. The result will be a much more visually pleasing rendering