Aspect Ratio Conversion Research Articles

Intelligence for Harmonizing Cloud-Based and On-Premises Workflows in Standards Conversion

<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Cloud computing offers significant benefits to broadcasters including the ability to scale up processing to meet peak or unexpected demands. Many broadcasters experience instances where material suddenly arrives in the wrong format for a given project or distribution network. Keeping a standards converter on standby for such situations is expensive and uses up valuable assets. In this paper, we describe a system that enables broadcasters to use in-house resources for regular operations, with intelligent offloading of critical or irregular processing demands into the cloud when required. Content arriving is analyzed and directed into the appropriate workflow path, for example, transcoding-only on-premise. Where a frame rate, format, or aspect ratio conversion is needed, the content can be directed to a cloud-based, motion-compensated, standards converter, where resources are allocated to meet the requirements of the job. We conclude with results from the evaluation of this system by a major German broadcaster</i> .

SpriteCam: virtual camera control using sprite

Editing or browsing video based on spatial content without distortion or cropping has been challenging because of providing unavailable information (view) in a single frame. Virtual camera control enables the user to view the video from her perspective by using camera functions such as pan, tilt, and zoom on a recorded video. In this paper, we propose our SpriteCam system that provides virtual camera controls by first generating the background sprite or mosaic of the video. We provide the theoretical framework and then explain how pan, tilt, and zoom operations are applied using the sprite. SpriteCam allows centralizing objects, aspect ratio conversion, and fixing the camera view without distortion or information loss for videos which sprite can be generated.

Aspect Ratio Problems in Television Today and Some New Solutions

The proliferation of video source formats, delivery mechanisms, and display devices has significantly increased broadcasters' needs for aspect ratio conversion. As a result, the authors have developed aspect processing, a framework for producing an arbitrary shape intelligently and flexibly. Aspect processing extends aspect ratio conversion to the definition of optimum viewing for a given screen size and shape. This paper presents new aspect processing technologies, which introduce a set of efficient criteria to automatically identify regions of interest in the picture and to process the picture accordingly. The paper also introduces a unique and novel technology—video seam carving, which works by altering the perspective of the image sequence to change between aspect ratios. These new technologies allow broadcasters to access new platforms and audiences with maximum re-use of systems and source material, resulting in a simpler and cheaper infrastructure.

Variable-field aspect-ratio transformer with cascaded graded-index oval-core fibers

A new configuration is proposed for continuously transforming aspect ratios of field-intensity distributions in optical fibers. The field aspect ratio varies in proportion to the angle between the principal axes of two cascaded graded-index oval-core fibers. The highest aspect-ratio conversion is obtained at an angle of 90 degrees. The conversion effect is numerically and experimentally confirmed, showing that a circular field is successfully transformed into an elliptical one with an aspect ratio as high as 9 at a wavelength of 0.98 microm.

A video backend for multimedia TV-sets

Advanced multimedia TV-sets can handle double scan TV sources (100 Hz, progressive scan, VGA, SVGA) with resolutions up to 800/spl times/600 at 60 Hz. In addition wide screens (16:9 aspect ratio) are attractive for displaying video and PC graphics side by side. This could become a key feature for WWW-ready TV-sets. So modern TV systems face two problems: displaying different scan rates and the compatibility of aspect ratios between TV/PC sources and picture tubes. This paper describes a highly integrated display and deflection processor (DDP). The mixed signal IC contains the entire digital video component processing like chroma transient improvement (CTI), adaptive luma peaking and a nonlinear Panorama aspect ratio conversion. All deflection related signals can be adapted to different scan rates. The analog section contains all analog interface components and an ADC, to compensate long term changes of the picture tube parameters and extreme high tension effects.

A flexible display module for DVD and set-top box applications

This paper presents a flexible, multi-mode display module for DVD and set-top box (STB) applications. The display module features: (1) vertical/horizontal post processing for chroma upsampling and rate conversions; (2) aspect ratio conversion for displaying 16:9 or 4:3 decoded pictures on either 16:9 or 4:3 devices; (3) user programmable, window based display with half or double window resizing; (4) sub-picture mixing and OSD overlay. All these functions are supported for both interlaced and progressive picture formats for PAL as well as NTSC systems.

MUSC/NTSC converter

The authors developed a home-use MUSE/NTSC (multiple subNyquist sample encoding/National Television System Committee) converter featuring basic or extended system selection capability. They describe the conversion algorithms, especially the aspect ratio conversion and scanning line decimation filtering from MUSE to NTSC. Five LSIs were developed for this system. Using this cost-effective converter, it is possible to watch MUSE programs on conventional TV sets. The system offers higher picture quality on TV sets with Y/C separated input or an RGB input.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>