Picture Quality Analysis System - PQA600
Contents
1. d 4 a __ 4 as 2 2 Se es LUI a oe ee p ht ECEE E BN IL 3 3 44 H SSH St ERN EM He oT tT ET L1 Pt ttt j dll E d I a DEI LHH Stet mm CC EN Fi L eH I _ tT ETT T _ dT L p B Modulation Sensitivity vs Spatial Frequency This model has been calibrated over the appropriate combinations of ranges for these parameters with reference stimulus response data from vision science research As a result of this calibration the model provides a highly accurate prediction 4 www tektronix com D Perceptual Contrast Map The graphs above are examples of scientifc data regarding human vision characteristics used to calibrate the human vision system model in the PQA600 Graph A shows modulation sensitivity vs temporal frequency and graph B shows modulation sensitivity vs spatial frequency The use of over 1400 calibration points supports high accuracy measurement results Picture C is a single frame from the reference sequence of a moving sequence and picture D is the perceptual contrast map calculated by the PQA600 The perceptual contrast map shows how the viewer perceives the reference sequence The blurring on the background is caused by temporal masking due to camera panning and the black area around the jogger shows the masking effect due to the high c2. Picture Quality Analysis System PQA600 Data Sheet Features amp Benefits Fast Accurate Repeatable and Objective Picture Quality Measurement Predicts DMOS Differential Mean Opinion Score based on Human Vision System Model Picture Quality Measurements can be made on a Variety of HD Video Formats 10801 720p and SD Video Formats 525i or 625i Makes Picture Quality Comparison across Different Resolutions from HD to SD or SD HD to CIF User confgurable Viewing Condition and Display Models for Reference and Comparison Attention Artifact Weighted Measurement Region Of Interest ROI on Measurement Execution and Review Automatic Temporal and Spatial Alignment Embedded Reference Decoder imported from MTS4EA Easy Regression Testing and Automation using XML Scripting with Export Import File from GUI Multiple Results View Options Optional SD HD SDI Interface with Simultaneous Generation Capture 2 channel Capture and 2 channel Generation with Swap channel Capability IP Interface with Simultaneous Generation Capture and 2 Ch Capture Cross Interface Confguration such as Generating from SDI and Capturing from IP or vice versa with Option SDI Preinstalled Sample Reference and Test Sequences Applications CODEC Design Optimization and Verifration Conformance Testing Transmission Equipment and System E valuation Digital Video Mastering Video Compression Services Digital Consumer P roduct Development and Ma
3. Capture Test IP Incoming uncompressed video Capture Reference SD HD SDI PQA600 Cross Interface Confguration To accommodate equipment processing delay that may be present in the system the user can use the Delay Start function when capturing video Using Delayed Start minimizes the number of unused overhead frames in the test fle and enables faster execution of the auto temporal alignment in the measurement Simultaneous 2 channel generation capability available only in SDI interface selection Supports two types of subjective testing With two displays the user can check the reference and test video content on side by side monitors With one display and swap channel capability the user can check the reference and test video content without moving the eye s focus point In any modes the user can Select the Cross Interface confguration such as generating from S DI and capturing from IP or vice versa The compressed video fle captured through IP will be converted to an uncompressed fle internally by an embedded reference decoder imported from MTS4EA Supported File Formats for SD HD SDI Interface The SD HD SDI video option can generate SDI video from fies in the following formats 8 bit unless otherwise stated yuv UYVY YUY2 V210 10 bit UYVY 3 components in 32 bits a rgb BGR24 Avi uncompressed BGR 32 discard alpha channel BGR24 UYVY YUY2 210 vcap created by PQA600 SDI video
4. CIF Display and Viewing D CINEMA Projector and Viewing 001 SD Broadcast PQR 002 HD Broadcast PQR 003 CIF and QVGA PQR 004 D CINEMA PQR Subjective Rating Predictions SD Display and Viewing HD Display and Viewing CIF Display and Viewing D CINEMA Projector and Viewing 005 SD Broadcast DMOS 006 HD Broadcast DMOS 007 CIF and QVGA DMOS 008 D CINEMA DMOS SD Broadcast CRT HD Broadcast CRT CIF QVGA LCD DMD Projector SD Broadcast CRT HD Broadcast CRT CIF QVGA LCD DMD Projector View Model NA ITU R BT 500 ITU R BT 500 7 scrn heights 20 cd m 3 scrn heights 1 cd m ITU R BT 500 ITU R BT 500 7 scrn heights 20 cd m 3 scrn heights 1 PSNR NA NA NA NA NA NA NA NA NA Perceptual Difference NA Typical Typical Typical Typical Typical Typical Typical Typical Artifact Detection NA NA NA NA NA NA NA NA NA Attention Model NA NA NA NA NA NA NA NA NA Configuration Nodes Display Model Summary Node PQR Units PQR Units PQR Units PQR Units DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training Attention Biased Subjective Rating Predictions SD Display and Viewing HD Display and Viewing CIF Display and Viewing SD Sports HD Spor
5. Simple Profle at Levels 0 5 and Advanced Simple Profie at Levels 0 5 H 263 Baseline System Layer Elementary streams contained within MPEG 2 Transport P rogram Stream MP4 Parts 1 12 and 15 ASF 3GPP DVD VOB Quicktime MOV Preinstalled Video Sequences Sequence Resolution Formats Clips Vclips 1920x1088 YUV4 2 0 planar V031202 Eigth Ave V031255 TimeSquare V031251 Stripy jogger 1920x1080 UYVY V031251 Stripy jogger 1280x720 UYVY YUV4 2 0 V031002 Eigth Ave planar V031055 TimeS quare V031051 Stripy jogger with 3 10 26 Mb s 864 486 YUV4 2 0 planar Converted V031051 Stripy jogger with 2 4 7 Mb s 320x180 YUV4 2 0 planar Converted V031051 Stripy jogger with 1000 1780 2850 Kb s PQA300 120x486 UYVY Ferris Flower Tennis without Trigger Cheer with 2 Mb s 25 fps 120x576 UYVY Auto BBC Ski Soccer PQA300 with 120x486 UYVY Mobile with 3 6 9 Mb s Trigger 720x516 UYVY Mobile with 3 6 9 Mb s Performance You Can Count On Depend on Tektronix to provide you with performance you can count on In addition to industry leading service and support this product comes backed by a one year warranty as standard www tektronix com 11 Data Sheet Characteristics Preconfigured Measurement Set Measurement Class View Video with No Measurement Measurement Name 000 View Video NA Subjective Prediction Full Reference Noticeable Differences SD Display and Viewing HD Display and Viewing
6. 026 Added NA Auto align spatial Selected NA Ringing NA dB units Edges Weighted Mosquito Noise _ COE WM _ S Rotated Edges 027 Rotated NA Auto align spatial Selected NA Edge Blockiness NA dB units Edges Weighted PSNR dB of Original 028 DC Blocking NA Auto align spatial Selected NA DC Blockiness NA dB units Deviation from Weighted PSNR Block DC dB Artifact Annoyance Weighted Filtered PSNR PSNR w 029 Artifact NA Auto align spatial Selected NA All artifacts NA dB units Default Artifact Annoyance selected Annoyance Weighted PSNR Weights dB www tektronix com 13 Data Sheet Measurement Measurement Configuration Nodes Class Name Display Model View Model PSNR Perceptual Artifact Attention Difference Detection Model Repurposing Use View Model to Resample Shift and Crop Test to Map to Reference Format 030 SD DVD NA Auto align spatial Selected NA All artifacts NA Conversion from D Cinema selected Cinema to SD Artifact weighted DVD PSNR dB Format 031 CIF from NA Auto align spatial Selected NA All artifacts NA Conversion SD SD Broadcast selected to CIF Artifact weighted PSNR dB Format 032 SD from NA Auto align spatial Selected NA All artifacts NA Conversion HD HD Broadcast selected to SD Artifact weighted PSNR dB Format 033 QCIF from NA Auto align spatial Selected NA All artifacts NA Conversion CIF CIF and QVGA selected to QCIF Artifact weighted PSNR dB Attention weighted Objective
7. A1 Universal Euro power A2 United Kingdom power A3 Australia power A4 240 V North America power A5 Switzerland power A6 J apan power A10 China power All India power Al2 Brazil power A99 No power cord or AC adapter Language Options Option Description LO English Manual L7 Simplifed Chinese Manual www tektronix com 15 Data Sheet Service Option Description CAl Single Calibration or Functional Verifration C3 Calibration Service 3 Years R3 Repair Service 3 Years IF Upgrade Installation Service Post sale Upgrade Option Description PQA6UP Field Upgrade Kit for PQA600 SDI SD HD SDI Interface for Field Installation Product Selection Feature PQASW PQA600 PSNR PQR DMOS Preconfgured Measurements Yes Yes Multi resolution F rame rate Support Yes Yes Multi results View Options Yes Yes Embedded Reference Decoder Yes Yes Automatic Temporal and S patial Alignment Yes Yes IP Generation Capture Opt IP Yes User confgurable Measurements Opt ADV Yes Attention Artifact Weighted Measurements Opt ADV Yes Script Execution Batch processing Opt ADV Yes Multiple Simultaneous Application Executions Opt ADV Yes SD HD SDI Generation and Capture No Opt SDI Cross Video Interface No Opt SDI Code Optimization Designated to the Platform No Yes Additional Information Please contact your local Service Manager for information regarding our products and services or contact us at www tektronix com serviceandsupportcontactus Tektr
8. A20 Rai d c pv Wen 40 41 087 0 921 Output Spatial ROI on Review mode for in depth investigation Region of Interest There are two types of spatial temporal Region of Interest ROI Input and Output Input ROIs are used to eliminate spatial or temporal regions from the measurement which are not of interest to the user For example Input Spatial ROI is used when running measurements for reference and test videos which have different aspect ratios Input Temporal ROI also known as temporal sync is used to execute measurements just for selected frames and minimize the measurement execution time Output ROIs can be used to review precalculated measurement results for only a subregion or temporal duration Output S patial ROI is instantly selected by mouse operation and gives a score for just the selected spatial area It s an effective way to investigate a specift spatial region in the difference map for certain impairments Output Temporal ROI is set by marker operation on the graph and allows users to get a result for just a particular scene when the video stream has multiple scenes It also allows users to provide a result without any inflience from initial transients in the human vision model Each parameter can be embedded in a measurement for the recursive operation Automated Testing with XML Scripting In the CODEC debugging optimizing process the designer may want to repeat several m
9. Full Reference or No Reference Picture Quality Peak Signal to Noise Ratio PSNR Full Reference Focus of Attention Applied to both Full Reference and No Reference Measurements Artifact Detection Full Reference except for DC Blockiness DC Blockiness Full Reference and No Reference Picture Quality Analysis System PQA600 Process ae 7 Medel J pitterence s Node 7 y n Hane Copia of 006 Broadcast DMOS Desenphon Perncephaal Di lference i DMOS Fredecbon Simulated BT 500 CAT displ eveers humar E dit Measure Dialog The PQA600 supports these measurements through preset and user defned combinations of display type viewing conditions human vision response demographic focus of attention and artifact detection in addition to the default ITU BT 500 conditions The ability to confpure measurement conditions helps CODEC designers evaluate design trade offs as they optimize for different applications and helps any user investigate how different viewing conditions affect picture quality measurement results A user defned measurement is created by modifying a preconfgured measurement or creating a new one then saving and recalling the user defned measurement from the Confgure Measure dialog menu Easy to Use Interface The PQA600 has two modes Measurement and Review The Measurement mode is used to execute the measurement selected in the Confgure Dialo
10. Measurements General Difference PSNR 034 Attention NA NA Selected NA NA Default Weightings Weighted PSNR dB Summary Node dB units dB units dB units dB units dB units Objective Measurements No Reference Artifact DC Blockiness 035 No NA NA NA NA No reference NA Reference DC DC Block Blockiness Percent Subjective Prediction Calibrated by Subjective Rating Conducted in 2009 with 1080i29 Video Contents and H 264 CODEC Refer to application note 28W 24876 0 HD ITU BT500 with Interlaced CRT HD DMOS ITU BT500 with Interlaced CRT HD ADMOS ITU BT500 with Interlaced CRT 14 www tektronix com Custom HD CRT Custom HD CRT Custom HD CRT 3 scrn heights 3 scrn heights 3 scrn heights NA NA NA Custom Custom Custom NA NA NA NA NA Typical DC Blockiness PQR Units DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training Nodes Node Name Configurable Parameter Display Model Display Technology CRT LCD DMD each with preset and user confgurable parameters Interlace P rogressive Gamma Response Time etc Reference Display and Test Display can be set independently View Model Viewing distance Ambient Luminance for Reference and Test independently image cropping and registration automatic or manual control of image cropping and test image contrast ac gain brightness dc offset horizontal and vertical scale and shift PSNR No con
11. capture vcap10 10 bit created by PQA600 video capture Option Supported Frame Formats Supported Geometry by SD HD SDI Interface SD SDI 720 486 720x576 5251 59 94 6251 50 HD SDI 1280x720 1920x1080 720p 50 720p 59 94 720p 60 10801 50 10801 59 94 10801 60 1080 23 98 1080p 23 98SF 1080p 24 1080p 24SF 1080p 25 1080p 29 97 1080p 30 Supported File Formats for IP Interface The IP interface option can generate and capture the compressed fle in the following formats mpg a trp Supported File Formats for Measurement All formats support 8 bit unless otherwise stated and measurements use SMSBs m yuv UYVY YUY2 YUV4 4 4 YUV4 2 0 planar V210 10 bit UYVY 3 components in 32 bits rgb BGR24 GBR24 Avi uncompressed BGR 32 discard alpha channel BGR24 UYVY YUY2 210 ARIB ITE format 4 2 0 planar with 3 separate fies yyy bbb rrr vcap created by PQA600 SDI video capture vcapl0 10 bit created by PQA600 video capture Picture Quality Analysis System PQA600 The following compressed fles are internally converted to an uncompressed fie before measurement execution Elementary Stream H 264 AVC MPEG 4 Part 10 Baseline Extended Main High 10 High 4 2 2 and High 4 4 4 profies all levels 1 to 5 1 MPEG 2 Main Profie at Main High and High 1440 levels 4 2 2 P rofle at Main and High Levels VC 1 All Profiles all Levels MPEG 4Part2
12. mobile transmission and videophone teleconferencing and more can all be evaluated separately or in any combination How It Works The PQA600 takes two video fies as inputs a reference video sequence and a compressed impaired or processed version of the reference First the PQA600 performs a spatial and temporal alignment between the two sequences without the need for a calibration stripe embedded within the video sequence Then the PQA600 analyzes the quality of the test video using measurements based on the human vision system and attention models and then outputs quality measurements that are highly correlated with subjective assessments The results include overall quality summary metrics frame by frame measurement metrics and an impairment map for each frame The PQA600 also provides traditional picture quality measures such as PSNR Peak Signal to Noise Ratio as an industry benchmark impairment diagnosis tool for measuring typical video impairments and detecting artifacts Each reference video sequence and test clip can have different resolutions and frame rates The PQA600 can provide picture quality measurement between HD vs SD SD vs CIF or any combination This capability supports a variety of repurposing applications such as format conversion DVD authoring IP broadcasting and semiconductor design The PQA600 can also support measurement clips with long sequence duration allowing a video clip to be quantifed for picture q
13. 52 0 124533 o 16401 14 36768 M 4 M pi HD Broadcast DMOS JOT Result File Sample imported to the measurement confyguration menu to create and manage the script fles easily Measurement results of the script operation can be viewed by using either the PQA600 user interface or any spreadsheet application that can read the created csv fie format as a summary Multiple scripts can be executed simultaneously for faster measurement results www tektronix com 9 Data Sheet 2 channel SDI Capture SD HD SDI Interface and IP Interface An SD HD SDI interface and IP interface enable both generation and capture of SDI video and IP video with three modes of simultaneous operation Simultaneous generation and capture lets the user playout the reference video clips directly from the PQA600 into the device under test The test output from the device can then be simultaneously captured by the PQA600 This saves the user from having to use an external video source to apply any required video input to the device under test With this generation capability fles created by video editing software can be directly used as reference and test sequences for picture quality measurements Simultaneous 2 channel capture lets the user capture two live signals to use as reference and test videos in evaluating the device under test in operation 10 www tektronix com Dra s 2 channel SDI Generation Encoder Outgoing compressed video s
14. IO Port Option SDI One front panel one rear panel Dual Link DVI I x1 Display x2 Up to 2560x1600 60 Hz 2 Ch Input 2 Ch Output with BNC to mini BNC SDI cable 174 5466 xx Physical Characteristics Benchtop Configuration Dimensions mm in Height 565 4 22 26 Width 215 9 8 5 Depth 538 5 22 3 Weight kg Ib Net 24 9 55 Picture Quality Analysis System PQA600 Ordering Information PQA600 Picture Quality Analysis System PC Monitor Requirement Note PQA600 does not include a PC monitor A monitor is to be provided by the user Dual Link DVI port or Display port Up to 2560x1600 resolution Included Accessories One year warranty plus the following Order Number Description PQA600 Picture Quality Analysis System Documentation 071 2775 xx Quick Start User Manual in English and Simplifed Chinese English apanese translation if a language option was ordered 071 2781 xx Release Notes 071 2778 xx User Technical Reference 077 0487 xx S pecifration and Performance Verifration Manual in PDF format on Documentation CD 077 0486 xx PQA600 Declassifration and Security Instructions in PDF format on Documentation CD 063 4284 xx Documentation CD containing PDF fles of the documentation set Other 020 3054 xx Application Recovery Disk 020 3053 xx Video Sequences Recovery M edia Options Option Description SDI SD HD SDI Interface International Power Plugs Option Description A0 North America power
15. a to SD DMOS ITU R BT 500 DVD Format 016 CIF from LCD and SD ITU R BT 500 NA Expert NA NA DMOS Units Re Conversion SD SD Broadcast Broadcast CRT and 7 scrn BT 500 Training to CIF DMOS heights 20 cd m Format 017 SD from SD and HD ITU R BT 500 NA Expert NA NA DMOS Units Re Conversion HD HD Broadcast Broadcast CRT BT 500 Training to SD DMOS Format 017 A SD from SD and HD ITU R BT 500 NA Expert NA NA DMOS Units Re Conversion SD HD Broadcast Progressive CRT BT 500 Training to HD DMOS Format 018 QCIF from QCIF and 7 scrn heights NA Expert NA NA DMOS Units Re Conversion CIF CIF and QVGA CIF QVGA LCD 20 cd m BT 500 Training to QCIF DMOS Attention Attention 019 Stand alone NA NA NA NA NA Default Map units Attention Model Weightings Probability of focus of attention Objective Measurements Full Reference General Difference Artifact Measurement Removed Edges 021 Removed NA Auto align spatial NA NA Blurring NA Edges Percent Added Edges 022 Added NA Auto align spatial NA NA Ringing NA Edges Percent Mosquito Noise Rotated Edges 023 Rotated NA Auto align spatial NA NA Edge Blockiness NA Edges Percent of Original 024 DC Blocking NA Auto align spatial NA NA DC Blockiness NA Deviation from Percent Block DC I Artifact Classified Filtered PSNR Removed Edges 025 Removed NA Auto align spatial Selected NA Blurring NA dB units Edges Weighted PSNR dB Added Edges
16. be recalled to the display for examination video in a Summary Six tiled or Overlaid display In Summary display the user can see the multiple measurement graphs with a barchart along with the reference video test video and difference map during video playback Summary measures of standard parameters and perceptual summation metrics for each frame and overall video sequence are provided In Six tiled display the user can display the 2 measurement results side by side Each consists of a reference video test video and difference map to compare to each other Automatic Temporal Spatial Alignment The PQA600 supports automatic temporal and spatial alignment as well as manual alignment The automatic spatial alignment with spatial region of interest in Measure mode selected independently of the spatial alignment function can measure the cropping scale and shift in each dimension even across different resolutions and aspect ratios for example when aligning SD to HD video If extra blanking is present within the standard active region itis measured as cropping when this function is enabled The automatic spatial and temporal alignment allows picture quality measurement between reference and test videos of different resolutions and frame rates 8 www tektronix com fide View Congue iuie Hep Wh v ea A0 ea en ens T uei Seek FOI E x Timm an SU She SAE als Covey AEU bert
17. del and Artifact Detection can also be used in conjunction with any combination of picture quality measurements This allows for example evaluation of how much of a particular noticeable artifact will be seen where a viewer is most likely to look 001 SD Broadcast PGR 002 HD Broadcast POR 003 CIF and QVGA 004 D CINEMA PQR 005 SD Broadcast DMOS 007 CIF and QVGA DMOS 008 D CINEMA DMOS 008 SD Broadcast ADMOS 010 HD Broadcast ADMOS Measure Description Attention Weighted Difference Mean Opinion Score ADMOS Prediction Simulated displays amp human vision system at a BT 500 viewing conditions Generally best prediction accuracy but slower Single Ended amp Dual Ended Reference C Video V031051 Stripy jogger 1280x 720p Browse Test CVideo V031051 Stripy jogger 1280x 720p 3ml Browse Format Show Import Export Setting Confgure Measure Dialog Comprehensive Picture Quality Analysis The PQA600 provides Full Reference FR picture quality measurements that compare the luminance signal of reference and test videos It also offers some No Reference NR measurements on the luminance signal of the test video only Reduced Reference RR measurements can be made manually from differences in No Reference measurements The suite of measurements includes Critical Viewing Human Vision System Model based Full Reference Picture Quality Casual Viewing Attention Weighted
18. e will be created Import E xport Script in Confgure Measure Dialog 2 Taktroni 006 HD Broadcast DMOS 3 Perteplu Difference Map amp DMOS Prediction Semulaed BT 500 interlaced CRT displinys amp typical sewers human Whon eystem at a sewing distance _ 4 Measure LurminanceOnly T 5 Summary Min 0 Max 100 Umts Rielerence rats lmpased ir ruts T amp Command Parameters 5 Measure T Dual Oey 10 Reference C Wiin AEU terining re A20 Bb 192101088 yuv 11 29 97 Sinscture poges Format Width 1820 Haight 12 Impared C Wid AELU tesian test 420 Ebi 190051088 13 Rate 29 97 Stactune pogessa Format YCBY CH 2 Width 1920 Height 14 Rieterence 1 End 100 15 Impuered 1 End 100 Result Maj 6 perceptual contrast 16 17 Decoder Fiederence B Saws Enabled Decoder Frame Co 100 Multiplier 1 Input SpatsLet px 0 Right px Top 0 Bottom oder Impared Samius Enabled Decoder Frame Cu 100 Multiplier 1 Input SpatiLet px 0 Right px Top px Bottom po Mean Abs Minkowski DMOS POR 954 5 10c101 0 173 0262653 0003494 DOTS 000587 821896 55 20 202 61541 0 971552 1005144 0010455 O01574 Q 152398 7 30 303 2 07411 4 7x3135 0009329 025023 TES 1355591 5B 0404 217319 4 312358 026574 0065572 0097052 6 13395 5 0550 5 1 26542358 058101 01113557 01531323 1253855 100 6 0 6 06 165166 206427 00701
19. easurement routines as CODEC parameters are revised Automated regression testing using XML scripting can ease the restrictions of manual operation by allowing the user to write a series of measurement sequences within an XML script The script fle can be exported from or Picture Quality Analysis System P QA600 LASLRE Dames de starzmetr l1 erndeefErame 807 ES st 271 endimpFrames dualended t references C videos au an ruf i20 abit ETE 01085 e 1920 Tefal ht 1085 refRates 239 97 p ode m refLefterape 1 000000 refR ttropes 1 000000 refToptrops 1 000 ef BottomCrope E d AEU tes e all par t 420 Ebit 1920x1088 ue dth 1920 EDI impRatee 239 87 1 Hess Juli 1 Mor irscale OOOO impor irshifte 0 000000 impvertscale mesa id vert t erm Cae PUTROLST Al tFrame 1 out puthozEndrr or BO SutputROILef te O ght refInputROILefte a ref InputRoT Right ref InputROITOpe T ref teputhorbot inpinputROlt eFt te Horircrope tr autoRelyv ertcr epa ET ue Wi X Mrs ue arpspvertcr ope true ir autoTemporalaligne true hos e 1 x block Script Sample Show Import Export Setting Import From script F video Measuresetting xml Export to script F video MeasureSetting xml Enter the name of the file ta be saved IF the file does not exist a new Fil
20. ensive constantly expanding collection of application notes technical briefs and other resources to help engineers working on the cutting edge of technology Please visit www tektronix com Copyright Tektronix Inc All rights reserved Tektronix products are covered by U S and foreign patents issued and pending Information in this publication supersedes that in all previously published material Specifration and price change privileges reserved TEKTRONIX and TEK are registered trademarks of Tektronix Inc All other trade names referenced are the service marks trademarks or registered trademarks of their respective companies 02 Oct 2011 25W 25447 4 Tektronix P
21. fgurable parameters Perceptual Difference The viewer characteristics acuity sensitivity to changes in average brightness response speed to the moving object sensitivity to photosensitive epilepsy triggers etc Attention Model Overall attention weighting for measures Temporal Motion Spatial Center People Skin Foreground Contrast Color Shape Size Distractions Differences Added Edges Blurring Removed Edges Ringing Mosquito Noise Rotated Edges Edge Blockiness and DC Blockiness Removed detail within a block Measurement Units Subjective Predicted DMOS PQR or Perceptual Contrast Objective Mean Abs LSB dB Map type Signed on gray or unsigned on black Worst case Training Sequence for ITU R BT 500 Training Default or User application Tuned Determined by Worst Case Video Perceptual Contrast Error Log Threshold Save Mode Artifact Detect Summary Node Computer System and Peripherals Component Description Operating System Windows 7 Professional 64 bit CPU S ix core Intel Xeon 5650 Series processors Hard Disk Drive 5x 3 5 in Total 5 TB SAS Serial Attached SCSI CD DVD Drive DVD RW CD R W drive Input Output Ports Port Description Power 100 240 V 50 60 Hz 115 V 230 V 6 A 3 A Keyboard Port PS 2 compatible Mouse Port PS 2 compatible USB 2 0 Port Two front panel six rear panel LAN Port Two RJ 45 connector supports 10 100 1000BASE T IEEE 1394 Port Graphics Port SDI
22. g During measurement execution the summary data and map results are displayed on screen and saved to the system hard disk The Review mode is used to view previously saved summary results and maps created either with the measurement mode or XML script execution The user can choose multiple results in this mode and compare each result side by side using the synchronous display in Tile mode Comparing multiple results maps made with the different CODEC parameters and or different measurement confgurations enables easy investigation of the root cause of any difference www tektronix com 7 Data Sheet Overlay display Reference and Map Integrated Graph RE ALPE Tien QU HT euin 12 man AT Deeps VE ede ams 120 Auto spatial alignment execution with spatial region of interest selected In Overlay display the user can control the mixing ratio with the fader bar enabling co location of difference map reference and impairments in test E Pra Verallel ISL nsa wages 1285 770g Ieri DAE 1417 TLE _ thea REM Six tiled display videos Error logging and alarms are available to help users efftiently track down Multiple Result Display the cause of video quality problems Resultant maps can be displayed synchronously with the reference and test All results data and graphs can
23. ge Blockiness Loss of Edges within an Image Block or DC Blockiness They work as weighting parameters for subjective and objective measurements with any combination The results of these different measurement combinations can help to improve picture quality through the system 6 www tektronix com Spatial Gradient Artifacts Enable Weighting 100 EJ Lost Edges Blurring C 100 gt Added Edges Ringing 100 Rotated Edges Blocking Produce complimentary data DR DC Blockiness Artifacts Enable Weighting 100 l 2 DC Blockiness Overall Artifact Weighting Artifact Detection Settings For example artifact detection can help answer questions such as Will the DMOS be improved with more de blocking fitering or Should less prefitering be used If edge blocking weighted DMOS is much greater than blurring weighted DMOS the edge blocking is the dominant artifact and perhaps more de blocking fitering should be considered In some applications it may be known that added edges such as ringing and mosquito noise are more objectionable than the other artifacts These weightings can be customized by the user and confgured for the application to refBctthis viewer preference thus improving DMOS prediction Likewise PSNR can be measured with these artifact weightings to determine how much of the error contributing to the PSNR measurement comes from each artifact The Attention Mo
24. nufacturing Picture Quality Analysis System The PQA600 is the latest generation Picture Quality Analyzer built on the Emmy Award winning Tektronix PQA200 300 Based on the concepts of the human vision system the PQA600 provides a suite of repeatable objective quality measurements that closely correspond with subjective human visual assessment These measurements provide valuable information to engineers working to optimize video compression and recovery and maintaining a level of common carrier and distribution transmission service to clients and viewers Tektronix Data Sheet User Interface of PQA600 Showing reference test sequences with difference map and Statistical graph Compressed Video Requires New Test Methods The true measure of any television system Is viewer Satisfaction While the quality of analog and full bandwidth digital video can be characterized indirectly by measuring the distortions of static test signals compressed television systems pose a far more diffrult challenge Picture quality in a compressed system can change dynamically based on a combination of data rate picture complexity and the encoding algorithm employed The static nature of test signals does not provide true characterization of picture quality 2 www tektronix com Human viewer testing has been traditionally conducted as described in ITU R Rec BT 500 11 A test scene with natural content and motion is displayed in a tightly contr
25. olled environment with human viewers expressing their opinion of picture quality to create a Differential Mean Opinion Score or DMOS Extensive testing using this method can be refned to yield a consistent subjective rating However this method of evaluating the capabilities of a compressed video system can be ineffrient taking several weeks to months to perform the experiments This test methodology can be extremely expensive to complete and often the results are not repeatable Thus subjective DMOS testing with human viewers is impractical for the CODEC design phase and ineffrient for ongoing operational quality evaluation The P QA600 provides a fast practical repeatable and objective measurement alternative to subjective DMOS evaluation of picture quality System Evaluation The PQA600 can be used for installation verifration and troubleshooting of each block of the video system because it is video technology agnostic any visible differences between video input and output from processing components in the system chain can be quantifed and assessed for video quality degradation Not only can CODEC technologies be assessed in a system but any process that has potential for visible differences can also be assessed For example digital transmission errors format conversion i e 1080i to 480p in set top box conversions 3 2 pull down analog transmission degradation data errors slow display response times frame rate reduction for
26. onix is registered to ISO 9001 and ISO 14001 by SRI Quality System Registrar GPIB Product s complies with IEEE Standard 488 1 1987 RS 232 C and with Tektronix Standard Codes and Formats www tektronix com Contact Tektronix ASEAN Australasia 65 6356 3900 Austria 00800 2255 4835 Balkans Israel South Africa and other ISE Countries 441 52 675 3777 Belgium 00800 2255 4835 Brazil 455 11 3759 7627 Canada 1 800 833 9200 Central East Europe and the Baltics 41 52 675 3777 Central Europe amp Greece 441 52 675 3777 Denmark 445 80 88 1401 Finland 41 52 675 3777 France 00800 2255 4835 Germany 00800 2255 4835 Hong Kong 400 820 5835 India 000 800 650 1835 Italy 00800 2255 4835 Japan 81 3 6714 3010 Luxembourg 441 52 675 3777 Mexico Central South America amp Caribbean 52 55 56 04 50 90 Middle East Asia and North Africa 41 52 675 3777 The Netherlands 00800 2255 4835 Norway 800 16098 People s Republic of China 400 820 5835 Poland 441 52 675 3777 Portugal 80 08 12370 Republic of Korea 001 800 8255 2835 Russia amp CIS 7 495 7484900 South Africa 41 52 675 3777 Spain 00800 2255 4835 Sweden 00800 2255 4835 Switzerland 00800 2255 4835 Taiwan 886 2 2722 9622 United Kingdom amp Ireland 00800 2255 4835 USA 1 800 833 9200 European toll free number If not accessible call 41 52 675 3777 Updated 10 February 2011 For Further Information Tektronix maintains a compreh
27. ontrast between the background and the jogger The PQA600 creates the perceptual map for both reference and test sequences then creates a perceptual difference map for use in making perceptually based full reference picture quality measurements E Reference Picture Quality Analysis System PQA600 G PSNR Map F Test Comparison of Predicted DMOS with PSNR In the example above Reference E is a scene from one of the VClips library fles The image Test F has been passed through a compression system which has degraded the resultant image In this case the background of the jogger in Test F is blurred compared to the Reference image E A PSNR measurement is made on the PQA600 of the difference between the Reference and Test clip and the highlighted white areas of PSNR Map G shows the areas of greatest difference between the original and degraded image Another measurement is then made by the PQA600 this time using the Predicted DMOS algorithm and the resultant Perceptual Difference Map for DMOS H image is shown Whiter regions H Perceptual Difference Map for DMOS in this Perceptual Contrast Difference map indicate greater perceptual contrast differences between the reference and test images In creating the Perceptual Contrast Difference map the P QA600 uses a human vision system model to determine the differences a viewer would perceive when watching the video The Predicted DMOS measurement uses the Perce
28. ptual Contrast Difference Map H to measure picture quality This DMOS measurement would correctly recognize the viewers perceive the jogger as less degraded than the trees in the background The PSNR measurement uses the difference map G and would incorrectly include differences that viewers do not see www tektronix com 5 Data Sheet Attention Map Example The jogger is highlighted Attention Model The PQA600 or PQASW Opt ADV also incorporates an Attention Model that predicts focus of attention This model considers Motion of Objects Skin Coloration to identify people Location Contrast Shape Size Viewer Distraction due to Noticeable Quality Artifacts These attention parameters can be customized to give greater or less importance to each characteristic This allows each measurement using an attention model to be user confgurable The model is especially useful to evaluate the video process tuned to the specift application For example if the content is sports programming the viewer is expected to have higher attention in limited regional areas of the scene Highlighted areas within the attention image map will show the areas of the image drawing the eye s attention Artifact Detection Artifact Detection reports a variety of different changes to the edges of the image Loss of Edges or Blurring Addition of Edges or Ringing Mosquito Noise Rotation of Edges to Vertical and Horizontal or Ed
29. ts SD Talking Head 009 SD Broadcast ADMOS 010 HD Broadcast ADMOS 011 CIF and QVGA ADMOS 012 SD Sports Broadcast ADMOS 013 HD Sports Broadcast ADMOS 014 SD Talking Head Broadcast ADMOS 12 www tektronix com SD Broadcast CRT HD Broadcast CRT CIF QVGA LCD SD Broadcast CRT HD Broadcast CRT SD Broadcast CRT ITU R BT 500 ITU R BT 500 7 scrn heights 20 cd m ITU R BT 500 ITU R BT 500 ITU R BT 500 NA NA NA NA NA NA Typical Typical Typical Typical Typical Typical NA NA NA NA NA NA Default Weightings Default Weightings Default Weightings Motion and Foreground Dominant Motion and Foreground Dominant Skin and Foreground Dominant DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training DMOS Units Re BT 500 Training Picture Quality Analysis System PQA600 Measurement Measurement Configuration Nodes Class Name Display Model View Model PSNR Perceptual Artifact Attention Summary Difference Detection Model Node Repurposing Reference and Test are Independent Use Any Combination Display Model and Viewing Conditions with Each Measurement Above Format 015 SD DVD DMD Projector 7 scrn heights NA Expert NA NA DMOS Units Re Conversion from D Cinema and SD CRT 20 cd m and BT 500 Training Cinem
30. uality through various conversion processes Prediction of Human Vision Perception PQA600 measurements are developed from the human vision system model and additional algorithms have been added to improve upon the model used in the PQA200 300 This new extended technology allows legacy PQR measurements for SD while enabling predictions of subjective quality rating of video for a variety of video formats HD SD CIF etc It takes into consideration different display types used to view the video for example interlaced or progressive and CRT or LCD and different viewing conditions for example room lighting and viewing distance Picture Quality Analysis System PQA600 Ref Cognitive Task Input TRE Vision based Format isplay iew Perceptual Attention Summary Conversion Mode PW Model P Model Measures 84 t Y Test a 1 Results Input Format Display View Picture Quality Analysis S ystem A model of the human vision system has been developed to predict the response to light stimulus with respectto the following parameters Contrast including Supra threshold Mean Luminance Spatial Frequency Temporal Frequency Angular Extent Temporal Extent Surround Eccentricity Orientation Adaptation Effects www tektronix com 3 Data Sheet E I LETT Se a JT T v1 CES E ITE MILL _ _
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