An analysis of almost 200 references has been carried out in order to obtain knowledge about the DEM (Digital Elevation Model) accuracy assessment methods applied in the last three decades. With regard to grid DEMs, 14 aspects related to the accuracy assessment processes have been analysed (DEM data source, data model, reference source for the evaluation, extension of the evaluation, applied models, etc.). In the references analysed, except in rare cases where an accuracy assessment standard has been followed, accuracy criteria and methods are usually established according to the premises established by the authors. Visual analyses and 3D analyses are few in number. The great majority of cases assess accuracy by means of point-type control elements, with the use of linear and surface elements very rare. Most cases still consider the normal model for errors (discrepancies), but analysis based on the data itself is making headway. Sample size and clear criteria for segmentation are still open issues. Almost 21% of cases analyse the accuracy in some derived parameter(s) or output, but no standardization exists for this purpose. Thus, there has been an improvement in accuracy assessment methods, but there are still many aspects that require the attention of researchers and professional associations or standardization bodies such as a common vocabulary, standardized assessment methods, methods for meta-quality assessment, and indices with an applied quality perspective, among others.

Heritage buildings traditionally have been tackled from several points of view: architectonic features, architectural style, archaeology, history, etc. Documents derived from those studies were classified and put together to form the documentation for consultation, taking decisions about its conservation, and restoration. Such a document organisation has some inconveniences: objects composing the building were treated as isolated objects not related to its adjacent objects. Nowadays technology may help to discover the relationship between architectural objects forming heritage buildings. The tool that makes it possible to include functionality in architectural objects is BIM (Building Information Modelling). In this paper the historical evolution of Saint Jeromés Church in Baza will be analysed and stored in a functional model which includes geometry and its current state. We propose a procedure for building the BIM through its historical roots and evolution to be included in each remarkable object modelled from the point cloud surveyed.

The field of Geographical Information Systems (GIS) has experienced a rapid and ongoing growth of available sources for geospatial data. This growth has demanded more data integration in order to explore the benefits of these data further. However, many data providers implies many points of view for the same phenomena: geospatial features. We need sophisticated procedures aiming to find the correspondences between two vector datasets, a process named geospatial data matching . Similarity measures are key-tools for matching methods, so it is interesting to review these concepts together. This article provides a survey of 30 years of research into the measures and methods facing geospatial data matching. Our survey presents related work and develops a common taxonomy that permits us to compare measures and methods. This study points out relevant issues that may help to discover the potential of these approaches in many applications, like data integration, conflation, quality evaluation, and data management.

This work presents the theoretical and practical aspects of the procedure to derive a Point Spread Function (PSF) of a SPOT image. The PSF of an image can be approximated by the use of linear step structures that are recorded in the image. Deconvolution filters are enhancement filters derived specifically for each image from its PSF, so that they can to restore the original signal for its use in cartographic remote sensing applied to cadastral proposes or urban areas.

Studies the accuracy and reliability of digital elevation models (DEMs) generated from two different satellite sources, the Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and the Systeme Pour l'Observation de la Terre (SPOT) High Resolution Visible (HRV) stereoscopic images, using three different photogrammetric softwares. The main reason for the study is the heterogeneity and absence of agreement found in previous research concerning several significant aspects of DEM generation methods. A set of 91 DEMs were generated from SPOT data and 55 DEMs from ASTER data. Error control was performed with 315 check points determined by differential global positioning systems. Results of Terra ASTER DEMs show that elevation RMSE (root mean square error) equals 13.0 m. The corresponding RMSE value for SPOT HRV DEM is 7.3 m. In both cases, the error is less than the pixel size. Furthermore, this communication proposes a technique to improve DEM structure, based on an objective criterion to cleanse redundancy in DEMs without a significant loss of accuracy. This criterion is based on removing all points with a correlation value below a threshold value.