Acquisition of 3D model of real objects and scenes is indispensable and useful in many practical applications, such as digital archives, game and entertainment industries, engineering, advertisement. There are 2 main methods for 3D acquisition : laser-based reconstruction (active method) and image-based reconstruction from multiple images of the scene in different points of view (passive method). While laser-based reconstruction achieves high accuracy, it is complex, expensive and difficult to set up for large-scale outdoor reconstruction. Image-based, or multi-view stereo methods are more versatile, easier, faster and cheaper. By the time we begin this thesis, most multi-view methods could handle only low resolution images under controlled environment. This thesis targets multi-view stereo both both in large scale and high accuracy issues. We significantly improve some previous methods and combine them into a remarkably effective multi-view pipeline with GPU acceleration. From high-resolution images, we produce highly complete and accurate meshes that achieve best scores in many international recognized benchmarks. Aiming even larger scale, on one hand, we develop Divide and Conquer approaches in order to reconstruct many small parts of a big scene. On the other hand, to combine separate partial results, we create a new merging method, which can merge automatically and quickly hundreds of meshes. With all these components, we are successful to reconstruct highly accurate water-tight meshes for cities and historical monuments from large collections of high-resolution images (around 1600 images of 5 M Pixel images)

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This thesis focuses on the design of a foveated stereo video compression algorithm for visual telepresence applications. In a typical telepresence application, a user at the local site views real-time stereo video recorded and transmitted from a robotic camera platform located at a remote site. The robotic camera platform tracks the user's head motion producing the sensation of being present at the remote site. The design of the stereo video compression algorithm revolved around a fast spatio-temporal block-based motion estimation algorithm, with a foveated SPIHT algorithm used to compress and foveate the independent frames and error residues. Also, the redundancy between the left and right video streams was exploited by disparity compensation. Finally, position feedback from the robotic camera platform was used to perform global motion compensation, increasing the compression performance without raising computation requirements. The algorithm was analysed by introducing the above mentioned components separately. It was found that each component increased the compression rate significantly, producing compressed video with similar compression and quality as MPEG2. The implementation of the algorithm did not meet the real-time requirements on the experiment computers. However, the algorithm does not contain any intrinsic delays. Therefore, given faster processors or optimized software implementation, the design should be able to run in real-time.

Abstract The Russia in which Isaak Babel (1894-1940) wrote was one of deep seated anti-Semitic philosophies and prejudices, a place of pogroms and segregation. Literature of this era painted the Jew as a villainous, dishonest, and feeble minded foreign being within society. Traditionally, Russian literature used the Jew as a national scapegoat or a comical stock character ripe for ridicule. Babel’s contemporaries considered him to be a born writer with a gift for minimalism without the sacrifice of vivid description. His was an evocative style of brutal humanism, showing both character flaws and character virtues. The Odesskie rasskazy (Odessa Tales) epitomized this honest approach to human portrayal. The Jewish community of the Odesskie rasskazy boasted a variety of characters from all walks of life, rejecting the previously perpetuated stereotype. The Jew, as shown by Pushkin, Turgenev, Dostoyevsky, Gogol, and Chekhov, was simply a caricature. Such characters were restricted to the role of the fool, the thief, and the opportunist. When Babel first described the community, people, and culture of his native shtetl, the previous stereotype of the Russian Jew became an antiquated relic of the past. This thesis will explore some examples of earlier depiction of Jews in literature and the humanized image of Russian Jewry that Babel created in his Odesskie rasskazy. The analysis will discuss how these depictions created a new, three dimensional characterization of the Jew.

Robotic manipulators have been introduced in industry as a form of increasing productivity. Today, there exist an interest to enlarge the application of these manipulators to outdoor environments. Forestry cranes used in the forestry industry are a clear example. A long term goal in this industry is the development of autonomous systems to increase the logging efficiency. In this thesis, we consider how to control the rotator of these cranes, which is an electro-hydraulically actuated motor, and is used to control the end ffector tool. Control system design for the rotator is a challenging task since the sensing is not available to full extent. The main reason is the harsh environment that these machines are exposed to and sensors such as encoders are very fragile and cannot be used. In this thesis we use alternative sensing devices, such as a magnetic sensor and a stereo camera. In the case of the camera we face a problem with big delay. A prediction method has been used to compute desired values. Due to various reasons certain measuring devices can not be used in the industry. We consider four cases for control system design where dfferent combinations of available sensors have been used. Initially angular position of the rotator is controlled using only the magnetic sensor. A cascade control setup is used where pressure and position are measurable, first using the magnetic sensor and later using the camera. When only pressure measurements are available identified models have replaced sensors for position feedback. All tests and experiments have been done using a scaled version of a real forestry crane. The available crane has similar configuration and dynamics as the real one and is therefor useful for experimental purposes.

The purpose of this master’s thesis was to study the possibility to use computer vision methods to detect and classify objects in the front passenger seat in a car. This work presents different approaches to solve this problem and evaluates the usefulness of each technique. The classification information should later be used to modulate the speed and the force of the airbag, to be able to provide each occupant with optimal protection and safety. This work shows that computer vision has a great potential in order to provide data, which may be used to perform reliable occupant classification. Future choice of method to use depends on many factors, for example costs and requirements on the system from laws and car manufacturers. Further, evaluation and tests of the methods in this thesis, other methods, the ABE approach and post-processing of the results should also be made before a reliable classification algorithm may be written.

This thesis focuses on the design of a foveated stereo video compression algorithm for visual telepresence applications. In a typical telepresence application, a user at the local site views real-time stereo video recorded and transmitted from a robotic camera platform located at a remote site. The robotic camera platform tracks the user's head motion producing the sensation of being present at the remote site. The design of the stereo video compression algorithm revolved around a fast spatio-temporal block-based motion estimation algorithm, with a foveated SPIHT algorithm used to compress and foveate the independent frames and error residues. Also, the redundancy between the left and right video streams was exploited by disparity compensation. Finally, position feedback from the robotic camera platform was used to perform global motion compensation, increasing the compression performance without raising computation requirements. The algorithm was analysed by introducing the above mentioned components separately. It was found that each component increased the compression rate significantly, producing compressed video with similar compression and quality as MPEG2. The implementation of the algorithm did not meet the real-time requirements on the experiment computers. However, the algorithm does not contain any intrinsic delays. Therefore, given faster processors or optimized software implementation, the design should be able to run in real-time.

Abstract The Russia in which Isaak Babel (1894-1940) wrote was one of deep seated anti-Semitic philosophies and prejudices, a place of pogroms and segregation. Literature of this era painted the Jew as a villainous, dishonest, and feeble minded foreign being within society. Traditionally, Russian literature used the Jew as a national scapegoat or a comical stock character ripe for ridicule. Babel’s contemporaries considered him to be a born writer with a gift for minimalism without the sacrifice of vivid description. His was an evocative style of brutal humanism, showing both character flaws and character virtues. The Odesskie rasskazy (Odessa Tales) epitomized this honest approach to human portrayal. The Jewish community of the Odesskie rasskazy boasted a variety of characters from all walks of life, rejecting the previously perpetuated stereotype. The Jew, as shown by Pushkin, Turgenev, Dostoyevsky, Gogol, and Chekhov, was simply a caricature. Such characters were restricted to the role of the fool, the thief, and the opportunist. When Babel first described the community, people, and culture of his native shtetl, the previous stereotype of the Russian Jew became an antiquated relic of the past. This thesis will explore some examples of earlier depiction of Jews in literature and the humanized image of Russian Jewry that Babel created in his Odesskie rasskazy. The analysis will discuss how these depictions created a new, three dimensional characterization of the Jew.

Examensarbetet undersöker vilken stereoteknik som uppfattas ge den mest verklighetstrogna återgivningen av konstmusik samt om valet av stereoteknik påverkas av ljudteknisk eller konstmusikalisk bakgrund. Undersökningen gjordes i form av ett lyssningstest där deltagare i tre grupper fick, efter att ha lyssnat till en konstmusikalisk ensemble live i en konsertlokal, lyssna till tio olika inspelningar av samma stycke vars enda skillnad var vilken stereoteknik som använts vid inspelningen. Deltagarna ombads att gradera hur väl inspelningarna speglade verkligheten samt rangordna dem efter vilka de ansåg låta bäst oavsett hur trogna verkligheten de var.Studiens resultat visar på att konstmusikalisk och ljudteknisk bakgrund påverkar valet av vilken stereoteknik man föredrar och vilken man tycker låter mest likt den verkliga upplevelsen av musiken live. Av resultatet kan man också utläsa att personer inte konsekvent anser att de inspelningar som låter mest verklighetstroget är den man anser låter bäst.

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