Enhancement of Underwater Video Mosaics for Post-Processing

Mosaics of seafloor created from still images or video acquired underwater have proved to be useful for construction of maps of forensic and archeological sites, species\u27 abundance estimates, habitat characterization, etc. Images taken by a camera mounted on a stable platform are registered (at first pair-wise and then globally) and assembled in a high resolution visual map of the surveyed area. While this map is usually sufficient for a human orientation and even quantitative measurements, it often contains artifacts that complicate an automatic post-processing (for example, extraction of shapes for organism counting, or segmentation for habitat characterization). The most prominent artifacts are inter-frame seams caused by inhomogeneous artificial illumination, and local feature misalignments due to parallax effects - result of an attempt to represent a 3D world on a 2D map. In this paper we propose two image processing techniques for mosaic quality enhancement - median mosaic-based illumination correction suppressing appearance of inter-frame seams, and micro warping decreasing influence of parallax effects

Mosaicing Tool for Aerial Imagery from a Lidar Bathymetry Survey

Aerial imagery collected during lidar bathymetry surveying provides an independent reference dataset for ground truth. Mosaicing of aerial imagery requires some manual involvement by the operator, which is time consuming. This paper presents an automatic mosaicing procedure that creates a continuous and visually consistent photographic map of the imaged area. This study aimed to use only the frames from the aerial camera without additional information. A comparison between the features in the resultant mosaic and a reference chart shows that the mosaic is visually consistent and there is good spatial-geometric correlation of features.Las imagenes aereas recogidas durante los levantamientos batimetricos efectuados con el lfdar proporcionan una coleccion de datos de referencia independientes para la validacion en el terreno. La composicion de las imagenes aereas en forma de mosaico requiere una cierta implicacion manual par parte del operador, to que toma mucho tiempo. Este articulo presenta un procedimiento para la composicion automatica en forma de mosaico, que crea un mapa fotografico continuo y visuatmente coherente de la zona representada en la imagen. El objetivo de este estudio es utilizar solo los marcos de la camara aerea sin informacion adicional. Una comparacion entre las caracterfsticas del mosaico resultante y una carta de referencia muestra que el mosaico es visualmente coherente y que hay una buena correlacion geometrico-espacial de las caracteristicas.L'imagerie aerienne effectuee pendant les leves bathymetriques lidar constitue un ensemble de donnees de reference independant, pour la realite de terrain. Le mosaiiquage de l'imagerie aerienne requiert une intervention manuelle de l'operateur, laquelle prend beaucoup de temps. Cet article presente une procedure de mosaiiquage automatique qui permet d'obtenir une carte photographique continue et visuellement coherente de la zone couverte. L'objectif de cette etude consiste a utiliser seulement les images de la camera aerienne sans informations supptementaires. Une comparaison entre tes elements dans la mosaique resultante et une carte de reference montre que la mosaique est visuellement coherente et qu'il existe une bonne correlation geometrique-spatiale des elements

An in Depth Review Paper on Numerous Image Mosaicing Approaches and Techniques

Image mosaicing is one of the most important subjects of research in computer vision at current. Image mocaicing requires the integration of direct techniques and feature based techniques. Direct techniques are found to be very useful for mosaicing large overlapping regions, small translations and rotations while feature based techniques are useful for small overlapping regions. Feature based image mosaicing is a combination of corner detection, corner matching, motion parameters estimation and image stitching.Furthermore, image mosaicing is considered the process of obtaining a wider field-of-view of a scene from a sequence of partial views, which has been an attractive research area because of its wide range of applications, including motion detection, resolution enhancement, monitoring global land usage, and medical imaging. Numerous algorithms for image mosaicing have been proposed over the last two decades.In this paper the authors present a review on different approaches for image mosaicing and the literature over the past few years in the field of image masaicing methodologies. The authors take an overview on the various methods for image mosaicing.This review paper also provides an in depth survey of the existing image mosaicing algorithms by classifying them into several groups. For each group, the fundamental concepts are first clearly explained. Finally this paper also reviews and discusses the strength and weaknesses of all the mosaicing groups

Mosaicing Tool for Aerial Imagery from a Lidar Bathymetry Survey

Aerial imagery collected during lidar bathymetry surveying provides an independent reference dataset for ground truth. Mosaicing of aerial imagery requires some manual involvement by the operator, which is time consuming. This paper presents an automatic mosaicing procedure that creates a continuous and visually consistent photographic map of the imaged area. This study aimed to use only the frames from the aerial camera without additional information. A comparison between the features in the resultant mosaic and a reference chart shows that the mosaic is visually consistent and there is good spatial-geometric correlation of features.Las imagenes aereas recogidas durante los levantamientos batimetricos efectuados con el lfdar proporcionan una coleccion de datos de referencia independientes para la validacion en el terreno. La composicion de las imagenes aereas en forma de mosaico requiere una cierta implicacion manual par parte del operador, to que toma mucho tiempo. Este articulo presenta un procedimiento para la composicion automatica en forma de mosaico, que crea un mapa fotografico continuo y visuatmente coherente de la zona representada en la imagen. El objetivo de este estudio es utilizar solo los marcos de la camara aerea sin informacion adicional. Una comparacion entre las caracterfsticas del mosaico resultante y una carta de referencia muestra que el mosaico es visualmente coherente y que hay una buena correlacion geometrico-espacial de las caracteristicas.L'imagerie aerienne effectuee pendant les leves bathymetriques lidar constitue un ensemble de donnees de reference independant, pour la realite de terrain. Le mosaiiquage de l'imagerie aerienne requiert une intervention manuelle de l'operateur, laquelle prend beaucoup de temps. Cet article presente une procedure de mosaiiquage automatique qui permet d'obtenir une carte photographique continue et visuellement coherente de la zone couverte. L'objectif de cette etude consiste a utiliser seulement les images de la camera aerienne sans informations supptementaires. Une comparaison entre tes elements dans la mosaique resultante et une carte de reference montre que la mosaique est visuellement coherente et qu'il existe une bonne correlation geometrique-spatiale des elements

Performance analysis on color image mosaicing techniques on FPGA

Today, the surveillance systems and other monitoring systems are considering the capturing of image sequences in a single frame. The captured images can be combined to get the mosaiced image or combined image sequence. But the captured image may have quality issues like brightness issue, alignment issue (correlation issue), resolution issue, manual image registration issue etc. The existing technique like cross correlation can offer better image mosaicing but faces brightness issue in mosaicing. Thus, this paper introduces two different methods for mosaicing i.e., (a) Sliding Window Module (SWM) based Color Image Mosaicing (CIM) and (b) Discrete Cosine Transform (DCT) based CIM on Field Programmable Gate Array (FPGA). The SWM based CIM adopted for corner detection of two images and perform the automatic image registration while DCT based CIM aligns both the local as well as global alignment of images by using phase correlation approach. Finally, these two methods performances are analyzed by comparing with parameters like PSNR, MSE, device utilization and execution time. From the analysis it is concluded that the DCT based CIM can offers significant results than SWM based CIM

Development Of A High Performance Mosaicing And Super-Resolution Algorithm

In this dissertation, a high-performance mosaicing and super-resolution algorithm is described. The scale invariant feature transform (SIFT)-based mosaicing algorithm builds an initial mosaic which is iteratively updated by the robust super resolution algorithm to achieve the final high-resolution mosaic. Two different types of datasets are used for testing: high altitude balloon data and unmanned aerial vehicle data. To evaluate our algorithm, five performance metrics are employed: mean square error, peak signal to noise ratio, singular value decomposition, slope of reciprocal singular value curve, and cumulative probability of blur detection. Extensive testing shows that the proposed algorithm is effective in improving the captured aerial data and the performance metrics are accurate in quantifying the evaluation of the algorithm

Toward the vision based supervision of microfactories through images mosaicing.

International audienceThe microfactory paradigm means the miniaturisation of manufacturing systems according to the miniaturisation of products. Some benefits are the saving of material, energy and place. A vision based solution to the problem of supervision of microfactories is proposed. It consists in synthetising a high resolution global view of the work field and real time inlay of local image in this background. The result can be used for micromanipulation monitoring, assistance to the operator, alarms and others useful informations displaying