DOCSLIB.ORG

Video Quality in the Digital OR

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Video Quality in the Digital OR Barco | Whitepaper Video Quality in the digital OR http://www.barco.com/healthcare Barco | Whitepaper Table of content Introduction 3 Enabling bright outcomes 3 Importance of Color quality during Surgery 3 Video integration in the Digital OR 3 Resolution 4 Resolution Size 4 Scaling and aspect ratio 5 Deinterlacing 6 Framerate 8 Introduction 8 Framerate at high resolution 8 Effect on latency 8 Effect on eye-fatigue 9 Color encoding schemes 10 RGB 10 YUV 10 Chroma Subsampling 11 Color Gamut 13 Definition 13 Viewing Angle 15 Color Calibration 16 White Balance 16 Color calibration on Surgical displays 16 Color Depth 17 Dithering 18 Compression 19 Latency 19 Conclusion 20 About the author 21 References 21 Definitions 21 P 2 / 21 Barco | Whitepaper Introduction Enabling bright outcomes The human eye is a fantastically complicated piece of instrumentation that performs its own image processing before the signal is relayed to the brain. The eye is very sensitive to color, motion, light, etc. The scope of this document is to explain how to provide the best possible quality to the eye of the Surgeon, to make sure the best outcomes can be reached for the patient. Importance of Color quality during Surgery More and more surgery is done with minimally invasive procedures, which limit the size of incisions needed and lessen wound healing time, associated pain and risk of infection. Minimally invasive procedures have been enabled by the advance of various medical technologies and instrumentation, including Endoscopic cameras and surgical displays. Some procedures are only performed this way, for example laparoscopy and arthroscopy. As explained in the Whitepaper “An Introduction to Color for Medical Imaging”1, surgery and examinations that use endoscopes need an exact representation of colors. The endoscope combined with the display can be considered an extension of the doctor’s eyes. The color of a wound for example provides an indication if a wound is healing. Video integration in the Digital OR In the surgical industry, multiple manufacturers produce different types of video sources and surgical displays. At first glance, the spec sheets of these sources and displays might look similar, but the quality specs of these products can be very different. It’s important to understand these specs when choosing the best possible product for your OR. Today a modern OR is often installed with a medical video integration system, connecting all components in the OR, including the video sources and displays. Again there are multiple manufacturers producing different types of integrated solutions which might look similar at first glance, but when looking at the quality specs there will be important differences. Does it make sense to purchase a 4K Endoscopic camera and connect an HD display to it? Is it a good choice to purchase best-in-class sources and displays but compromise on quality in the video distribution system? Is it an issue to have multiple displays in the OR, each showing the same source with different color settings? This document describes the various video quality specs to consider when choosing the best product for your needs. P 3 / 21 Barco | Whitepaper Resolution Resolution Size Over the years, many different video resolutions were generated by different medical instrumentation. While the aspect ratio may vary, the general trend is that newer applications use higher resolutions. The table below shows some commonly used resolutions and their aspect ratios. Many applications used in the OR have a long lifetime. Therefore there are still many devices in use today with lower resolutions and legacy video interfaces (e.g. S-Video, Composite and VGA). The content sent out by these devices is however very important for many procedures. Therefore the video integration system in the Digital OR must be capable of supporting these legacy video interfaces and resolutions, along with newer technology. The benefits of 4K are described in the whitepaper “4K in the operating room”2. 4K surgical displays developed today typically have a native timing of UHD (3840x2160) or True 4K (4096x2160). Since today’s ORs have devices with a variety of interfaces and resolutions, look for an integration solution which can support a wide range of video interfaces and resolutions for all your devices, both old and new. Confirm that this solution does not change the resolution at any point in the video chain, except at the display where it is scaled to the display resolution. P 4 / 21 Barco | Whitepaper Scaling and aspect ratio When an image is upscaled from a low resolution source to a higher resolution display, the scaling algorithm must invent pixels which are as close as possible to how adjacent pixels look. When an image is downscaled from a high resolution source to a lower resolution display, the scaling algorithm must calculate average pixel values to output the image correctly. By doing that, the quality of the image is reduced, because in most cases all pixels must be recalculated. There are many techniques to make this scaling as good as possible, with errors low enough for the result to appear visually lossless. If a scaled image is scaled a second time this becomes worse, because the errors in the scaling algorithm get multiplied. Therefore an installation should aim to scale the video as little as possible. The worst-case scenario would be a system with a lot of scalers and conversion boxes which scale the image multiple times before it is shown on a display. The best-case scenario is a system where the resolution of the source is identical to the resolution of the display. In such a scenario, the image does not need to be scaled and there is no loss in image quality. When scaling is needed, the aspect ratio should always be preserved to ensure an accurate image. The images below show an example of scaling done with an incorrect aspect ratio. Correct aspect ratio Incorrect aspect ratio - stretched When the aspect ratio of the source is not the same as the aspect ratio of the display, black borders must be added on top and bottom or left and right of the image to ensure the aspect ratio is correct. Look for a video integration solution with as few conversion boxes as possible, and with displays that match the resolution of your most critical sources (typically the endoscopic camera). Confirm that the aspect ratio is not changed at any point in the video chain. P 5 / 21 Barco | Whitepaper Deinterlacing Video interfaces can use two types of scanning methods to draw the picture: interlaced and progressive. All digital displays are progressive-scan displays. Even if the video interface provides the video with an interlaced scanning, the display will convert this to progressive scan before it is shown on the display. This process is called deinterlacing. • Progressive scan In this scanning method, the entire image is drawn at once. No deinterlacing is required. • Interlaced scan In this scanning method, only half of the picture is sent every frame. In the first field, the odd lines are transmitted. In the second field, the even lines are transmitted. The two fields combined result in a full frame. Field 1 Field 2 An interlaced image which is transmitted at 60 fields per second results in 30 complete frames per second. When video transmission was invented, the electronics in displays were not fast enough to process 60 complete images per second. Also the bandwidth of interfaces to transmit the image to the display did not allow this. With an interlaced scanning method, only half of the image needs to be processed. In those days, the display first drew the odd lines and then the even lines. Another benefit that this gave is that the image was refreshed 60 times per second even though only 30 frames were sent. Even though the complete frame did not receive new video content, the viewer perceived this as a higher framerate, resulting in less flickering and more fluent video. Today, digital displays convert the video to progressive before displaying the image. Therefore this benefit is not relevant anymore. Interlaced video is common on analog broadcast standards like PAL/NTSC and used on early computer systems. Interlaced video is rarely used in digital video interfaces, except the SDI standard. The DVI standard does not define interlaced timings, but some CCUs send out 1080i on this interface. P 6 / 21 Barco | Whitepaper • Deinterlacing A deinterlacing algorithm will buffer one field and combine it with the other field to create a full frame. There are different techniques to do this, each with their own advantages and disadvantages. Almost all deinterlacing techniques add some latency because the display needs both fields before it can send the image to the display. • Weaving Weaving is done by simply combining the two fields. The advantage is that the quality of the source image is not touched: the output shows exactly what the source provided. A disadvantage is that fast moving parts in the frame will create an artefact called “combing”. • Blending Blending is done by calculating the average pixel values for consecutive frames. Combing is avoided this way, but another artefact called “ghosting” appears: fast moving parts will be shown two times. This method also causes a quality loss in the complete image, because the image must be downsized and then upsized, losing vertical resolution. Another disadvantage is that this causes some extra latency. • Selective blending This method is a combination of weaving and blending. Areas of the frame that don’t change use weaving. Areas of the frame that change use blending. To be able to do this, a motion detection algorithm must be used to indicate what parts of the frame move and which don’t.
Load more

Recommended publications
  • Adaptive Quantization Matrices for High Definition Resolutions in Scalable HEVC
    Original citation: Prangnell, Lee and Sanchez Silva, Victor (2016) Adaptive quantization matrices for HD and UHD display resolutions in scalable HEVC. In: IEEE Data Compression Conference, Utah, United States, 31 Mar - 01 Apr 2016 Permanent WRAP URL: http://wrap.warwick.ac.uk/73957 Copyright and reuse: The Warwick Research Archive Portal (WRAP) makes this work by researchers of the University of Warwick available open access under the following conditions. Copyright © and all moral rights to the version of the paper presented here belong to the individual author(s) and/or other copyright owners. To the extent reasonable and practicable the material made available in WRAP has been checked for eligibility before being made available. Copies of full items can be used for personal research or study, educational, or not-for profit purposes without prior permission or charge. Provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way. Publisher’s statement: © 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. A note on versions: The version presented here may differ from the published version or, version of record, if you wish to cite this item you are advised to consult the publisher’s version.
    [Show full text]
  • Dell 24 USB-C Monitor - P2421DC User’S Guide
    Dell 24 USB-C Monitor - P2421DC User’s Guide Monitor Model: P2421DC Regulatory Model: P2421DCc NOTE: A NOTE indicates important information that helps you make better use of your computer. CAUTION: A CAUTION indicates potential damage to hardware or loss of data if instructions are not followed. WARNING: A WARNING indicates a potential for property damage, personal injury, or death. Copyright © 2020 Dell Inc. or its subsidiaries. All rights reserved. Dell, EMC, and other trademarks are trademarks of Dell Inc. or its subsidiaries. Other trademarks may be trademarks of their respective owners. 2020 – 03 Rev. A01 Contents About your monitor ......................... 6 Package contents . 6 Product features . .8 Identifying parts and controls . .9 Front view . .9 Back view . 10 Side view. 11 Bottom view . .12 Monitor specifications . 13 Resolution specifications . 14 Supported video modes . 15 Preset display modes . 15 MST Multi-Stream Transport (MST) Modes . 16 Electrical specifications. 16 Physical characteristics. 17 Environmental characteristics . 18 Power management modes . 19 Plug and play capability . 25 LCD monitor quality and pixel policy . 25 Maintenance guidelines . 25 Cleaning your monitor. .25 Setting up the monitor...................... 26 Attaching the stand . 26 │ 3 Connecting your monitor . 28 Connecting the DP cable . 28 Connecting the monitor for DP Multi-Stream Transport (MST) function . 28 Connecting the USB Type-C cable . 29 Connecting the monitor for USB-C Multi-Stream Transport (MST) function. 30 Organizing cables . 31 Removing the stand . 32 Wall mounting (optional) . 33 Operating your monitor ..................... 34 Power on the monitor . 34 USB-C charging options . 35 Using the control buttons . 35 OSD controls . 36 Using the On-Screen Display (OSD) menu .
    [Show full text]
  • Detectability Model for the Evaluation of Lossy Compression Methods on Radiographic Images Vivek Ramaswami Iowa State University
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1996 Detectability model for the evaluation of lossy compression methods on radiographic images Vivek Ramaswami Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Electrical and Electronics Commons Recommended Citation Ramaswami, Vivek, "Detectability model for the evaluation of lossy compression methods on radiographic images" (1996). Retrospective Theses and Dissertations. 250. https://lib.dr.iastate.edu/rtd/250 This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Detectability model for the evaluation of lossy compression methods on radiographic images by Vivek Ramaswami A thesis submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Major: Electrical Engineering Major Professors: Satish S. Udpa and Joseph N. Gray Iowa State University Ames, Iowa 1996 Copyright © Vivek Ramaswami, 1996. All rights reserved. 11 Graduate College Iowa State University This is to certify that the Master's thesis of Vivek Ramaswami has met the t hesis requirements of Iowa State University Signature redacted for privacy 111 TABLE OF CONTENTS ACKNOWLEDGEMENTS IX 1 INTRODUCTION . 1 2 IMAGE COMPRESSION METHODS 5 201 Introduction o 0 0 0 0 0 5 2o2 Vector quantization 0 0 ..... 5 20201 Classified vector quantizer 6 20202 Coding of shade blocks o .....
    [Show full text]
  • EN User Manual 1 Customer Care and Warranty 28 Troubleshooting & Faqs 32 Table of Contents
    499P9 www.philips.com/welcome EN User manual 1 Customer care and warranty 28 Troubleshooting & FAQs 32 Table of Contents 1. Important ...................................... 1 1.1 Safety precautions and maintenance ................................. 1 1.2 Notational Descriptions ............ 3 1.3 Disposal of product and packing material .......................................... 4 2. Setting up the monitor .............. 5 2.1 Installation .................................... 5 2.2 Operating the monitor .............. 9 2.3 Built-in Windows Hello™ pop- up webcam .................................14 2.4 MultiClient Integrated KVM .....16 2.5 MultiView ..................................... 17 2.6 Remove the Base Assembly for VESA Mounting ..........................18 3. Image Optimization ..................19 3.1 SmartImage .................................19 3.2 SmartContrast ............................20 3.3 Adaptive Sync .............................21 4. HDR ............................................. 22 5. Technical Specifications ......... 23 5.1 Resolution & Preset Modes ...26 6. Power Management ................ 27 7. Customer care and warranty . 28 7.1 Philips’ Flat Panel Displays Pixel Defect Policy ..............................28 7.2 Customer Care & Warranty ...... 31 8. Troubleshooting & FAQs ......... 32 8.1 Troubleshooting ........................ 32 8.2 General FAQs ............................. 33 8.3 Multiview FAQs .........................36 1. Important discoloration and damage to the 1. Important monitor. This electronic
    [Show full text]
  • Impact of Adaptation Dimensions on Video Quality
    Impact of Adaptation Dimensions on Video Quality Jens Brandt and Lars Wolf Institute of Operating Systems and Computer Networks (IBR), Technische Universitat¨ Braunschweig, Germany [email protected] Abstract—The number and types of mobile devices which well as the network conditions, may vary more often over time are capable of presenting digital video streams is increasing compared to static devices. Thus, the experience of watching constantly. In most cases the devices are trade-offs between video streams on mobile devices differs to a great extent from powerful all-purpose computers and small mobile devices which are ubiquitously available and range from cellular phones to those scenarios related to static displays usually found in the notebooks. This great heterogeneity of mobile devices makes area of home entertainment. For sequences from soccer games video streaming to such devices a challenging task for content McCarthy et al. observed that potential users preferred lower providers. Each single device has its own capabilities and indi- frame rates but higher detail resolution on mobile devices [2]. vidual requirements, which need to be considered when sending For other genres similar findings were presented for scalable a video stream to it. Thus, to support a great range of different devices, the video streams need to be adapted to the requirements video coding by Eichhorn and Ni in [3]. Besides concentration of each device. To get an idea of how different adaptation methods solely on the temporal resolution of a video stream, in our may affect the experience of users watching a streamed video on a work we additionally investigated the effect of adapting the mobile device, we inspect the influence of three major adaptation spatial and the detail resolution as well.
    [Show full text]
  • Developed by the Consumer Technology Association Video Division
    4K Ultra High-Definition TV A display system may be referred to as 4K Ultra High-Definition if it meets the following minimum performance attributes: Display Resolution – Has at least 8 million active pixels, with at least 3840 horizontally and at least 2160 vertically. Physical pixels shall be individually addressable such that the horizontal and vertical resolution above can be demonstrated over the full range of colors provided by the display. Aspect Ratio – The width to height ratio of the display’s native resolution is 16:9 or wider. Upconversion – The display is capable of upscaling HD video and displaying it at 4K Ultra High- Definition display resolution. Digital Input – Has one or more HDMI inputs supporting at least 3840x2160 native content resolution at 24p, 30p, & 60p frames per second. At least one of the 3840x2160 HDMI inputs shall support HDCP v2.2 or equivalent content protection. Colorimetry – Processes 2160p video inputs encoded according to ITU-R BT.709 color space, and may support wider colorimetry standards. Bit Depth – Has a minimum bit depth of 8 bits. Connected 4K Ultra High-Definition TV A display system may be referred to as Connected 4K Ultra High-Definition (or Connected 4K UHD) if it meets the following minimum performance attributes: 4K Ultra High-Definition Capability – Meets all of the requirements of CTA’s 4K Ultra High-Definition Display Characteristics V3. Video Codec – Decodes IP-delivered video of 3840x2160 resolution that has been compressed using HEVC* and may decode video from other standard encoders. Audio Codec – Receives and reproduces, and/or outputs multichannel audio.
    [Show full text]
  • The H.264 Advanced Video Coding (AVC) Standard
    Whitepaper: The H.264 Advanced Video Coding (AVC) Standard What It Means to Web Camera Performance Introduction A new generation of webcams is hitting the market that makes video conferencing a more lifelike experience for users, thanks to adoption of the breakthrough H.264 standard. This white paper explains some of the key benefits of H.264 encoding and why cameras with this technology should be on the shopping list of every business. The Need for Compression Today, Internet connection rates average in the range of a few megabits per second. While VGA video requires 147 megabits per second (Mbps) of data, full high definition (HD) 1080p video requires almost one gigabit per second of data, as illustrated in Table 1. Table 1. Display Resolution Format Comparison Format Horizontal Pixels Vertical Lines Pixels Megabits per second (Mbps) QVGA 320 240 76,800 37 VGA 640 480 307,200 147 720p 1280 720 921,600 442 1080p 1920 1080 2,073,600 995 Video Compression Techniques Digital video streams, especially at high definition (HD) resolution, represent huge amounts of data. In order to achieve real-time HD resolution over typical Internet connection bandwidths, video compression is required. The amount of compression required to transmit 1080p video over a three megabits per second link is 332:1! Video compression techniques use mathematical algorithms to reduce the amount of data needed to transmit or store video. Lossless Compression Lossless compression changes how data is stored without resulting in any loss of information. Zip files are losslessly compressed so that when they are unzipped, the original files are recovered.
    [Show full text]
  • EN User Manual 1 Customer Care and Warranty 27 Troubleshooting & Faqs 31 Table of Contents
    B Line 346B1 www.philips.com/welcome EN User manual 1 Customer care and warranty 27 Troubleshooting & FAQs 31 Table of Contents 1. Important ...................................... 1 9.3 Multiview FAQs .........................34 1.1 Safety precautions and maintenance ................................. 1 1.2 Notational Descriptions ............ 3 1.3 Disposal of product and packing material .......................................... 3 2. Setting up the monitor .............. 5 2.1 Installation .................................... 5 2.2 Operating the monitor .............. 8 2.3 MultiClient Integrated KVM ......11 2.4 MultiView .....................................12 2.5 Remove the Base Assembly for VESA Mounting ..........................14 3. Image Optimization ..................16 3.1 SmartImage .................................16 3.2 SmartContrast ............................. 17 3.3 Adaptive Sync .............................18 4. Designs to prevent computer vision syndrome (CVS) .............19 5. PowerSensor™ ..........................20 6. Technical Specifications ......... 22 6.1 Resolution & Preset Modes ...25 7. Power Management ................26 8. Customer care and warranty . 27 8.1 Philips’ Flat Panel Displays Pixel Defect Policy .............................. 27 8.2 Customer Care & Warranty .....30 9. Troubleshooting & FAQs .......... 31 9.1 Troubleshooting ......................... 31 9.2 General FAQs ............................. 32 1. Important proper cooling of the monitor’s 1. Important electronics. This electronic user’s
    [Show full text]
  • Overview of the MPEG 4 Standard
    ).4%2.!4)/.!,/2'!.)3!4)/.&/234!.$!2$)3!4)/. /2'!.)3!4)/.).4%2.!4)/.!,%$%./2-!,)3!4)/. )3/)%#*4#3#7' #/$).'/&-/6).'0)#452%3!.$!5$)/ )3/)%#*4#3#7'. $ECEMBER-AUI 3OURCE 7'-0%' 3TATUS &INAL 4ITLE -0%' /VERVIEW -AUI6ERSION %DITOR 2OB+OENEN /VERVIEWOFTHE-0%' 3TANDARD %XECUTIVE/VERVIEW MPEG-4 is an ISO/IEC standard developed by MPEG (Moving Picture Experts Group), the committee that also developed the Emmy Award winning standards known as MPEG-1 and MPEG-2. These standards made interactive video on CD-ROM and Digital Television possible. MPEG-4 is the result of another international effort involving hundreds of researchers and engineers from all over the world. MPEG-4, whose formal ISO/IEC designation is ISO/IEC 14496, was finalized in October 1998 and became an International Standard in the first months of 1999. The fully backward compatible extensions under the title of MPEG-4 Version 2 were frozen at the end of 1999, to acquire the formal International Standard Status early 2000. Some work, on extensions in specific domains, is still in progress. MPEG-4 builds on the proven success of three fields: • Digital television; • Interactive graphics applications (synthetic content) ; • Interactive multimedia (World Wide Web, distribution of and access to content) MPEG-4 provides the standardized technological elements enabling the integration of the production, distribution and content access paradigms of the three fields. More information about MPEG-4 can be found at MPEG’s home page (case sensitive): http://www.cselt.it/mpeg . This web page contains links to a wealth of information about MPEG, including much about MPEG-4, many publicly available documents, several lists of ‘Frequently Asked Questions’ and links to other MPEG-4 web pages.
    [Show full text]
  • Instruction Manual
    HEM-790IT_EN_SP_r2.qxd 11/19/09 9:57 AM Page 1 INSTRUCTION MANUAL Automatic Blood Pressure Monitor with ComFitTM Cuff Model HEM-790IT ESPAÑOL ENGLISH HEM-790IT_EN_SP_r2.qxd 11/19/09 9:57 AM Page 2 TABLE OF CONTENTS Before Using the Monitor Introduction . .4 Safety Information . .5 Operating the Device . .5 Risk of Electrical Shock . .7 Care and Maintenance . .7 Before Taking a Measurement . .8 Operating Instructions Know Your Unit . .9 Unit Display . .11 Display Symbols . .12 Irregular Heartbeat Symbol . .12 Movement Error Symbol . .12 USER ID Symbol . .12 Morning Hypertension Symbol . .13 Heartbeat Symbol . .14 Average Value Symbol . .14 Morning Average Symbol . .14 Evening Average Symbol . .14 Battery Installation . .15 Using the AC Adapter . .17 Setting the Date and Time . .19 Applying the Arm Cuff . .23 2 HEM-790IT_EN_SP_r2.qxd 11/19/09 9:57 AM Page 3 TABLE OF CONTENTS Taking a Measurement . .27 Using the Guest Mode . .27 Selecting the USER ID . .28 Using the USER ID . .28 Selecting the TruReadTM Mode . .29 Using the Single Mode . .31 Using the TruReadTM Mode . .34 Special Conditions . .36 Using the Memory Function . .37 Averaging Function . .37 To Display the Measurement Values . .38 Morning and Evening Averages . .40 Morning Averages . .40 Evening Averages . .40 To Display Morning and Evening Averages . .41 Display Combinations . .42 To Delete All Values Stored in the Memory . .43 Downloading Instructions Installing the Software . .44 Downloading and Installing Microsoft® HealthVaultTM . .44 Downloading and Installing Omron® Health Management Software . .46 Using the Software . .48 Care and Maintenance Care and Maintenance . .52 Error Indicators and Troubleshooting Tips .
    [Show full text]
  • VA2719-2K-Smhd Display User Guide
    VA2719-2K-smhd Display User Guide IMPORTANT: Please read this User Guide to obtain important information on installing and using your product in a safe manner, as well as registering your product for future service. Warranty information contained in this User Guide will describe your limited coverage from ViewSonic Corporation, which is also found on our web site at http://www.viewsonic.com in English, or in specific languages using the Regional selection box in the upper right corner of our website. “Antes de operar su equipo lea cu idadosamente las instrucciones en este manual” Model No. VS16861 Thank you for choosing ViewSonic As a world leading provider of visual solutions, ViewSonic is dedicated to exceeding the world’s expectations for technological evolution, innovation, and simplicity. At ViewSonic, we believe that our products have the potential to make a positive impact in the world, and we are confident that the ViewSonic product you have chosen will serve you well. Once again, thank you for choosing ViewSonic ! Contents 1. Cautions and Warnings ..................................... 1 2. Getting Started ................................................... 4 2-1. Package Contents ............................................................. 5 2-2. The Exterior of the Monitor ................................................ 6 2-3. Hardware Installation ........................................................ 7 2-4. Quick Installation ............................................................. 11 2-5. Power On .......................................................................
    [Show full text]
  • Video Resolution - an Overview from Robert Silva, Nov 16 2005
    Video Resolution - An Overview From Robert Silva, Nov 16 2005 The Basics A television or recorded video image is basically made up of scan lines. Unlike film, in which the whole image is projected on a screen at once, a video image is composed of rapidly scanning lines across a screen starting at the top of the screen and moving to bottom. These lines can be displayed in two ways. The first way is to split the lines into two fields in which all of the odd numbered lines are displayed first and then all of the even numbered lines are displayed next (this is in analog video formats. Digital video switches this, displaying even number lines first then odd number lines- this is what is meant by field dominance), in essence, producing a complete frame. This process is called interlacing or interlaced scan. The second method, used in digital video recording, digital TVs, and computer monitors, is referred to as progressive scan. Instead of displaying the lines in two alternate fields, progressive scan allows the lines to displayed sequentially. This means that both the odd and even numbered lines are displayed in numerical sequence. Analog Video: NTSC/PAL/SECAM The number of vertical scan lines dictates the capability to produce a detailed image, but there is more. It is obvious at this point that the larger the number of vertical scan lines, the more detailed the image. However, within the current arena of video, the number of vertical scan lines is fixed within a system. The current analog video systems are NTSC, PAL, and SECAM.
    [Show full text]