Evaluating the accuracy of vehicle tracking data obtained from Unmanned Aerial Vehicles

Abstract This paper presents a methodology for tracking moving vehicles that integrates Unmanned Aerial Vehicles with video processing techniques. The authors investigated the usefulness of Unmanned Aerial Vehicles to capture reliable individual vehicle data by using GPS technology as a benchmark. A video processing algorithm for vehicles trajectory acquisition is introduced. The algorithm is based on OpenCV libraries. In order to assess the accuracy of the proposed video processing algorithm an instrumented vehicle was equipped with a high precision GPS. The video capture experiments were performed in two case studies. From the field, about 24,000 positioning data were acquired for the analysis. The results of these experiments highlight the versatility of the Unmanned Aerial Vehicles technology combined with video processing technique in monitoring real traffic data

Identifying related landmark tags in urban scenes using spatial and semantic clustering

There is considerable interest in developing landmark saliency models as a basis for describing urban landscapes, and in constructing wayfinding instructions, for text and spoken dialogue based systems. The challenge lies in knowing the truthfulness of such models; is what the model considers salient the same as what is perceived by the user? This paper presents a web based experiment in which users were asked to tag and label the most salient features from urban images for the purposes of navigation and exploration. In order to rank landmark popularity in each scene it was necessary to determine which tags related to the same object (e.g. tags relating to a particular café). Existing clustering techniques did not perform well for this task, and it was therefore necessary to develop a new spatial-semantic clustering method which considered the proximity of nearby tags and the similarity of their label content. The annotation similarity was initially calculated using trigrams in conjunction with a synonym list, generating a set of networks formed from the links between related tags. These networks were used to build related word lists encapsulating conceptual connections (e.g. church tower related to clock) so that during a secondary pass of the data related network segments could be merged. This approach gives interesting insight into the partonomic relationships between the constituent parts of landmarks and the range and frequency of terms used to describe them. The knowledge gained from this will be used to help calibrate a landmark saliency model, and to gain a deeper understanding of the terms typically associated with different types of landmarks

Estimating the Available Sight Distance in the Urban Environment by GIS and Numerical Computing Codes

The available sight distance (ASD) is that part of the roadway ahead which is visible to the driver, and should be of sufficient length to allow a vehicle traveling at the designated speed to stop before reaching a stationary object in its path. It is fundamental in assessing road safety of a project or on an existing road section. Unfortunately, an accurate estimation of the available sight distance is still an issue on existing roads, above all due to the lack of information regarding the as-built condition of the infrastructure. Today, the geomatics field already offers different solutions for collecting 3D information about environments at different scales, integrating multiple sensors, but the main issue regarding existing mobile mapping systems (MMSs) is their high cost. The first part of this research focused on the use of a low-cost MMS as an alternative for obtaining 3D information about infrastructure. The obtained model can be exploited as input data of specific algorithms, both on a GIS platform and in a numerical computing environment to estimate ASD on a typical urban road. The aim of the investigation was to compare the performances of the two approaches used to evaluate the ASD, capturing the complex morphology of the urban environment

A Navigation and Augmented Reality System for Visually Impaired People

In recent years, we have assisted with an impressive advance in augmented reality systems and computer vision algorithms, based on image processing and artificial intelligence. Thanks to these technologies, mainstream smartphones are able to estimate their own motion in 3D space with high accuracy. In this paper, we exploit such technologies to support the autonomous mobility of people with visual disabilities, identifying pre-defined virtual paths and providing context information, reducing the distance between the digital and real worlds. In particular, we present ARIANNA+, an extension of ARIANNA, a system explicitly designed for visually impaired people for indoor and outdoor localization and navigation. While ARIANNA is based on the assumption that landmarks, such as QR codes, and physical paths (composed of colored tapes, painted lines, or tactile pavings) are deployed in the environment and recognized by the camera of a common smartphone, ARIANNA+ eliminates the need for any physical support thanks to the ARKit library, which we exploit to build a completely virtual path. Moreover, ARIANNA+ adds the possibility for the users to have enhanced interactions with the surrounding environment, through convolutional neural networks (CNNs) trained to recognize objects or buildings and enabling the possibility of accessing contents associated with them. By using a common smartphone as a mediation instrument with the environment, ARIANNA+ leverages augmented reality and machine learning for enhancing physical accessibility. The proposed system allows visually impaired people to easily navigate in indoor and outdoor scenarios simply by loading a previously recorded virtual path and providing automatic guidance along the route, through haptic, speech, and sound feedback

Vertical Video Trends Among Amateur Digital Platform Users as an Alternative for Film Production

The Vertical Video Syndrome expression adequately represents the spread of the production process and projection of amateur digital content in vertical format. For smartphone users, the vertical is the king. All components of digital life make users subconsciously hold their phones vertically on various occasions. Penetration after penetration is carried out, from flexibility and artificial intelligence, to private viewing rooms that move dynamically. As a new starting point in quite an extended period, the vertical video gives birth to a glimmer of hope in a film atmosphere that seems exclusive and rigid. However, problems have arisen as user demands have increased and smartphones have become sociocultural necessity over the last decade. With a vertical screen, people are used to spending time watching video shows, including recording all their activities. Because of that, there is a big challenge for filmmakers to see the opportunities that exist. The vertical format creates a narrow, elongated reading space. The camera movement, which used to use action from left to right, now switches from top to bottom. Subjects in vertical formats are also forced to submit to limited reading space. In conventional films, close-ups can isolate the field of view while at the same time emphasizing facial expressions. But not vertically because it will bring out a different density; what arises is not a close-up but a big close-up and even an extreme close-up. As a result, this gives motivation and a different meaning visually. It would be a lie if this didn't fall into the challenges to be solved. The field of view gets more complicated. The vertical concept encourages creators to get out of the conventional mindset. Likewise, with the actors involved, the vertical format provides a more challenging exploration of expressions and gestures. This research uses qualitative methods in collecting data and utilizes a lot of current literature. The research results are in the form of knowledge and recommendations regarding the packaging and distribution of film production in a vertical format. Tren Video Vertikal di Antara Pengguna Platform Digital Amatir sebagai Alternatif Produksi Film. Sindrom Video Vertikal, ungkapan itu cukup mewakili merebaknya proses produksi dan proyeksi konten digital amatir berformat vertikal. Bagi pengguna smartphone, vertikal adalah raja. Seluruh komponen kehidupan digital membuat pengguna secara alam bawah sadar memegang telepon secara vertikal dalam beragam kesempatan. Penetrasi demi penetrasi dilakukan, fleksibilitas, kecerdasan buatan, hingga ruang tonton privasi yang bergerak dinamis. Sebagai titik pijak baru dalam kurun waktu yang cukup panjang, video vertikal melahirkan secercah harapan dalam suasana perfilman yang terkesan eksklusif dan kaku. Namun, persoalan pun muncul, di kala tuntunan pengguna semakin tinggi dan smartphone menjadi kebutuhan sosiokultural sejak satu dekade terakhir. Dengan layar vertikal, orang terbiasa menghabiskan waktu untuk menonton tayangan video termasuk merekam segala aktivitasnya. Karena itulah, muncul tantangan besar bagi pembuat film guna melihat peluang yang ada. Format vertikal mencipta ruang baca yang menyempit memanjang. Memindahkan pergerakan kamera yang terbiasa memanfaatkan pergerakan dari kiri ke kanan, kini beralih dari atas ke bawah. Subjek pada format vertikalpun dipaksa untuk tunduk pada ruang baca yang terbatas. Pada film konvensional, close-up sudah mampu mengisolasi ruang pandang sekaligus mempertegas ekspresi wajah. Namun tidak pada vertikal karena akan memunculkan kepadatan yang berbeda, yang timbul bukan close-up melainkan big close-up bahkan extreme close-up. Alhasil ini memberi motivasi dan makna yang berbeda secara visual. Suatu kebohongan jika ini tidak masuk dalam kategori tantangan yang harus dipecahkan. Ruang pandang menjadi sedikit lebih rumit. Konsep vertikal benar-benar mendorong kreator untuk keluar dari pola pikir konvensional. Begitu pula dengan aktor yang terlibat, format vertikal memberikan tantangan eksplorasi yang lebih pada ekspresi dan gerak tubuh. Penelitian ini menggunakan metode kualitatif dalam mengumpulkan data dan memanfaatkan banyak literatur saat ini. Hasil penelitian berupa pengetahuan dan rekomendasi tentang pengemasan dan distribusi produksi film dalam format vertikal