VEE and DPO Hardware and Software Integration
Contents
1. e Select deselect Auto Brightness e Adjust brightness even with Auto Brightness enabled using the methods described earlier e Select deselect VEE e Manually adjust VEE strength MDDO assumes that the system is using standard Android APIs for communicating with and controlling ambient light information and display backlight If non standard methods are used the software must be modified to work within the system framework contact QuickLogic This application is optional and not required to receive the benefits of VEE and DPO but is strongly recommended for ideal implementation of the technologies to best improve user experience For information on the coding within the program contact QuickLogic Additionally this application can be customized in appearance to suit a particular OEM or system designer need 2011 QuickLogic Corporation P R E LI M l NA RY www quicklogic com 11 12 QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A Running MDDO in a System with a CSSP On startup MDDO verifies that veeapp apk is installed in the proper Android layer When found MDDO automatically requests that the veeapp apk change the backlight and VEE strength in real time If veeapp apk is running in the background as daemon run it from console with the following command Veeapp d i m2 Alternatively type the following command line in init rc2. High Bacllight Strength Low T n ON oOonNoOOnNOQONn ONON ON ONON oOoOoNnoOoOonNnNnonnoo KNA AN ORHAN OTDHRH ADA CTOKhRHN DOKRH NDR HN DOR WH AN MM TH DOR DADAAANRNMTH HOR DDH A Saeed e se ttt eat aaa lux Setting Up VEE and DPO Modes VEE and DPO modes can be set up in multiple ways e Visual restoration e Visual restoration and power savings e Visual improvement e Visual improvement and power savings Visual Restoration VEE is set up in this mode to restore the viewing quality of the display to a level that is typically seen in a good viewing environment lower ambient light with a bright display DPO is not active in this mode as backlight is never changed Figure 3 shows a graphical interpretation of visual improvement versus visual restoration www quicklogic com P R E LI M l NA RY 2011 QuickLogic Corporation QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A Figure 3 VEE Visual Restoration VEE Visual Restoration High VEEStrength Low Dark TOTO TTT OT TTL HITT LLALLA EN TIT VOUE TI TOU TUE TOY PETE TOT EY ONT EN Te Vee dee vee neve eee eee eeee eee ee ee ee No Toe Ne Noe ee ene eee ete eed ee eT et eT Ambient Light Level Lux Bright Visual Restoration and Power Savings VEE is setup in this mode to restore the viewing quality of the dis
3. Brightness enabled Auto Visual Enhancement Automatically adjusts VEE compensation based on current ambient light and backlight level Individual user preference setting for VEE compensation Adjusts VEE compensation even with Auto Visual Enhancement enabled Auto Visual Enhancement with manual backlight control Auto Brightness deselected In this mode adjusts VEE compensation based on the current ambient light level and the user s manual backlight setting Implements a socket client to communicate user selections with VEEapp daemon www quicklogic com P R E LI M l NA RY 2011 QuickLogic Corporation QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A QIAutoAl apk Mobile Device Display Optimizer QuickLogic s MDDO Q1AutoAl apk is an Android application designed to replace the standard Auto Brightness window within Android in systems with a QuickLogic CSSP featuring VEE and DPO see Figure 8 Figure 8 MDDO Settings QuickLogic Mobile Device Display Optimizer 5 2 23 PM M Ambient Light Level Ix Web Images Places News more v Suggested Back Light Level Current Back Light Level 7 Google i Barto Brightness Q f Display Brightness i Wao Visual Enhancement Visual Enhancement zz Sign in iGoogle Settings Help View Google in Mobile Classic Go to Google com 2011 Privacy MDDO allows the user to
4. Display 1 Display 2 Brightness 350 cd m 2 200 cd m 2 Overall power logic BLU 3 4W 2 6W BLU power max 2 4W 1 6W Computed logic power 1 0W 1 0W Viewing angle horizontal 89 degrees 45 degrees As shown the performance is very different especially in the areas of power consumption and brightness Since VEE works to improve visibility and DPO works to lower power consumption the variances between these displays illustrates the need to calibrate for individual system characteristics 2011 QuickLogic Corporation P R E LI M l NA RY www quicklogic com 3 QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A Creating the Auto Backlight Curve QuickLogic starts by using the ambient light versus backlight curve created by the system designer This curve also known as the Auto Backlight curve is best created by testing actual display performance with a properly calibrated ambient light sensor However testing has shown that most Auto Backlight curves are not properly created These findings and recommendations for improvements are available in a separate QuickLogic white paper entitled Auto Brightness How to Improve the Android Mobile Operating System in Handheld Consumer Devices This paper can be obtained by contacting QuickLogic Figure 2 shows a typical auto backlight curve Figure 2 Typical Auto Backlight Curve
5. the design product or intellectual property as one possible implementation of your desired system level feature application or standard QuickLogic makes no representation that this implementation is free from any claims of infringement and any implied warranties of merchantability or fitness for a particular purpose You are responsible for obtaining any rights you may require for your system implementation QuickLogic shall not be liable for any damages arising out of or in connection with the use of the design product or intellectual property including liability for lost profit business interruption or any other damages whatsoever QuickLogic products are not designed for use in life support equipment or applications that would cause a life threatening situation if any such products failed Do not use QuickLogic products in these types of equipment or applications QuickLogic does not assume any liability for errors which may appear in this document However QuickLogic attempts to notify customers of such errors QuickLogic retains the right to make changes to either the documentation specification or product without notice Verify with QuickLogic that you have the latest specifications before finalizing a product design Copyright and Trademark Information Copyright 2011 QuickLogic Corporation All Rights Reserved The information contained in this document is protected by copyright All rights are reserved by QuickLogic Corporation Quick
6. the path depends on where veeapp apk is located in the Android build service VEE data veeapp d i m2 oneshot Running MDDO in a System without a CSSP The MDDO software can be operated on a system without a CSSP solution platform containing VEE This is useful because it allows the system designer to immediately see what impact VEE has on the viewability of their system display It also allows QuickLogic and the system designer to create a VEE and DPO calibration table prior to inclusion of a CSSP into the system design On startup if veeapp apk is not detected in the proper Android layer MDDO will always default to simulation mode When run without a CSSP MDDO provides a visual simulation of VEE strength changes by using a standard deck of j pg files provided by QuickLogic showing varying VEE strengths MDDO can also display an image of the system designer s choice contact QuickLogic for details To run MDDO in a system without a CSSP install the files on the Android SD card or other removable media directory in a folder called QuUickLogic VEE all Name the files 000 jpg 001 jpg etc corresponding to VEE strength levels How the VEE and DPO Software Communicates Within Android Within Android there are four main layers see Figure 6 on page 9 e Applications written in java executing in Dalvik e Application Framework services and libraries written mostly in java applications and mo
7. Logic Corporation reserves the right to modify this document without any obligation to notify any person or entity of such revision Copying duplicating selling or otherwise distributing any part of this product without the prior written consent of an authorized representative of QuickLogic is prohibited QuickLogic and ArcticLink are registered trademarks and the QuickLogic logo is a trademark of QuickLogic Other trademarks are the property of their respective companies 13 2011 QuickLogic Corporation P R E LI M l NA RY www quicklogic com
8. QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide QuickLooic 3 e eee QuickLogic White Paper Introduction A display looks best when viewed in a dark room with the brightness set to maximum However maximum brightness translates into shorter system battery life with the additional detraction of a lower display lifetime for organic light emitting diode OLED displays Typically system designers will reduce brightness to lengthen battery life However reduction in display brightness leads to a degradation of image quality particularly when ambient light washes out the display content with reflected light This effect is particularly pronounced with some newer OLED touchscreen displays but is present on all commonly used displays in mobile handsets smartphones tablets and other handheld consumer devices The developer must choose whether to allow the display to operate at increased brightness levels to increase viewability but sacrifice battery life or conserve battery life but negatively affect the user experience in display viewability QuickLogic s VEE and DPO proven system blocks PSBs can increase display viewability in all lighting conditions while extending battery life The VEE greatly enhances the viewability of mobile device displays under challenging viewing conditions such as bright ambient light by dynamically optimizing vid
9. dependent of Android light sensor service Talk to any Android application through a socket client interface e Provides the capability to read write ArcticLink II VX solution platform registers in command line mode which is a good hardware debugging tool and useful during the calibration process 2011 QuickLogic Corporation P R E LI M l NA RY www quicklogic com 9 10 QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A Figure 7 VEEApp Interaction RGB Display Communication with actual Ambient light sensor hardware Android MDDI Driver 12C Driver PWM Driver SPI Device file Device file Device file sysiclass power_supply kernel driversfi2c jf sys class eds cd battery lluminometer backlight brightness Provided by Quicklogic Monitor changesin ambient light sensor Can change and or monitor backlight thru Android Adjust VEE strength from the data in the calibration table Do all the above tasks based on user settings Settings apk The settings apk file provides reference Java code for the brightness settings dialog which can replace the original Android Backlight Settings menu GUI implementation includes Auto Brightness Automatically adjusts backlight based on the current ambient light Individual user preference setting for brightness Adjusts brightness even with Auto
10. e low contrast ratio of mobile displays to bring a more television like viewing experience to mobile devices 2011 QuickLogic Corporation P R E LI M l NA RY www quicklogic com 1 QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A While the VEE uses statistical information gathered pixel by pixel frame by frame to adjust the value of individual pixels the DPO uses that same information to adjust the backlight The ability to provide a unique tone curve for each pixel as well as have tight control over the display backlight gives greater flexibility than the global adjustments of alternative implementations The QuickLogic approach results in greater power savings and the entirely new capability of adapting to a bright environment DPO seamlessly integrates with VEE ensuring longer battery life and an excellent visual experience by coupling the pulse width modulation PWM driving the display backlight with the display content processing parameters of the VEE technology VEE and DPO are hardware based technologies integrated into consumer devices via a Customer Specific Standard Product CSSP solution platform from QuickLogic The CSSP is placed in the display path between the CPU applications processor and the display as shown in Figure 1 Figure 1 VEE and DPO in a System Shown with a TAOS Ambient Light Sensor E QuickLogic MDDI RGB CPU B
11. e method Backlight is modulated by instruction of the CSSP through the existing processor or Super I O device via a PWM or the CSSP drives it directly on board PWM e Veeapp daemon determines optimum VEE strength and display backlight level for ambient light conditions by use of calibration table The calibration table is created during product development by an original equipment manufacturer OEM and QuickLogic One calibration table is completed and is appropriate for all systems built with the same bill of materials same display ALS and processor Backlight level and VEE strength are adjusted to provide the best possible viewing experience and power savings per the calibration table The CSSP can be programmed for immediate changes to backlight VEE strength with ambient light changes or for a breathing effect for smoother changes User adjustments to backlight are accounted for through the calibration table VEE and DPO are fully capable of automatic operation with a standard auto brightness curve or manual brightness settings Creating the VEE and DPO Calibration Table VEE and DPO must be calibrated for unique system characteristics such as displays and processors due to differences in performance For instance two displays can be of equal size and resolution but perform much differently Table 1 lists the specifications of two different displays of equal size from the same manufacturer Table 1 Display Examples
12. eo characteristics to provide a natural viewing experience while DPO works in concert to reduce display backlight or power levels extending system battery life as much as 36 VEE and DPO Technology QuickLogic s VEE technology enables a television quality visual experience on portable devices This technology delivers the next generation of mobile entertainment experience by adapting display data in real time to improve the user s viewing experience under difficult conditions such as low backlight or in bright ambient light QuickLogic s proven VEE solution greatly enhances image and video quality for handset users by compressing the dynamic range to match the characteristics of the display resulting in a substantially better viewing experience QuickLogic s VEE technology is based on the iridix algorithm from Apical Limited iridix is an implementation of a set of algorithms based on the orthogonal retina morphic image transform ORMIT developed by Apical Limited and protected by multiple patents It is a sophisticated method of dynamic range compression DRC which differs from conventional methods such as gamma correction in that it applies different tonal and color transformations to every pixel in an image These algorithms implement a model of human perception which results in a displayed image that retains detail color and vitality even under difficult viewing conditions VEE technology specifically addresses the problem of th
13. f the test system is lowered until the viewability of the two systems is as close as possible The VEE strength is changed if necessary to make this happen VEE and display backlight strengths are recorded as well as the power consumption of both systems This process is repeated for all backlight levels in the auto backlight curve Table 1 shows an example of a typical calibration Table 2 VEE and DPO Auto Backlight Calibration Results Display Backlight DPC Enabled VEE Strength Control System Display Backlight Test System 10 25 50 10 50 30 60 15 150 35 65 25 225 40 70 30 500 45 80 35 1 250 60 90 40 10 000 80 100 50 50 000 100 100 60 This approach is designed for a restoration approach of VEE Most OEMs use a combination of restoration and enhancement For this as the ambient light level increases the system designer can choose to lower backlight while increasing VEE strength beyond a restoration level to produce a situation with enhanced viewability while still saving power These measured values provide a VEE curve for an auto backlight implementation Calibrating Manual Brightness The setup values established for auto brightness may not be appropriate if the user manually adjusts the backlight significantly beyond what is normal for ambient lighting VEE must compensate to avoid over or under compensation 2011 QuickLogic Corporation P R E LI M l NA RY w
14. form to correctly operate VEE and DPO VEEApp is programmed to the customer s unique system by QuickLogic and requires no development work on the part of the system designer www quicklogic com P R E LI M l NA RY 2011 QuickLogic Corporation QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A Figure 6 Android Operating System APPLICATIONS Contacts Phone Browser APPLICATION FRAMEWORK Brightness Activity Manager Window Content View Setting Manager Providers System amp QuickLogic Telephony Resource Location Notification Package Manager we Manager Manager Manager Manager LIBRARIES ANDROID RUNTIME Surface Manager Media A Core Libraries ramewor OpenGL ES FreeType SGL SSL avaoge LINUX KERNEL Camera Driver Flash Memory Binder IPC Driver Driver Display Driver Audio Power Keypa river WiFi Drive eypad Drive iFi Driver Drivers Management The VEEApp application e Communicates with the ArcticLink II VX solution platform through I C drivers in the system see Figure 7 e Communicates with Android light sensor and backlight control services to Receive events from Android regarding ambient light and display brightness level changes from Android and adjusts VEE operation Change the display brightness level through Android Poll the ambient light level at a defined interval through I C drivers in
15. improvement curves A curve closer to restoration is generally applied to low ambient light levels where image details and thus artifacts are much more noticeable An improvement curve tends to be used in the higher ambient light levels where sheer viewability is more important than absolute image quality www quicklogic com P R E LI M l NA RY 2011 QuickLogic Corporation QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A Calibration Setup To create a VEE and DPO calibration table QuickLogic and the system designer begin with two units of the final system design containing the CSSP with VEE One of those systems becomes the test system while the other one becomes the control system Calibrating Auto Brightness To calibrate the auto brightness both systems are placed in an ambient lighting environment that simulates the lowest step in the auto backlight curve generated earlier with VEE and DPO turned off in both systems QuickLogic s Mobile Device Display Optimizer MDDO software is installed to speed development Using MDDO a standard still image is displayed on both screens Without changing the ambient light level VEE is set at approximately 50 strength on the test system A noticeable change will occur in visibility of that system allowing it to be much more viewable to the engineers calibrating the system The display backlight o
16. ong with the good content DPO is not active in this mode as backlight is never changed Figure 5 shows a graphical interpretation of visual improvement versus visual restoration Figure 5 VEE Visual Restoration vs Visual Improvement VEE Visual Restoration VEE Visual Improvement High VEEStrength Low IT VELTUT HITT TOT TTT TENE TEED TUTE TET TTT TOOT TT TEE TONE TEN TOE TEEN TOE TENE TIT VER TONE VEN TOT NTE PTE NYE ee AE ee PoE Ta NT eT Ae no ee Ae ne Pee eee ee ae eee a eo ee ee ee Dark Ambient Light Level Lux Bright Visual Improvement and Power Savings VEE is set up in this mode to improve the viewing quality of the display to the best level possible by applying VEE strength as strong as possible While VEE does not create artifacts in the display content artifacts or noise present in the source display content will be amplified along with the good content Additionally DPO works in concert with VEE to actively adjust the backlight based on the current ambient lighting conditions as measured by the Ambient Light Sensor to the lowest level possible without negatively affecting the viewing experience Changing VEE strength does not increase device power consumption thus there is no difference between VEE power consumption when used in restoration or improvement modes In actual application most OEMs choose an implementation of VEE that falls between the restoration and
17. play to a level that is seen in a good viewing environment lower ambient light with a bright display Additionally DPO works in concert with VEE to actively adjust the backlight based on current ambient light conditions as measured by an Ambient Light Sensor such as the TAOS TSL2571 to the lowest level possible without negatively affecting the viewing experience While actual power savings depends on the specific display and system characteristics typical system battery savings that original equipment manufacturers OEMs have achieved in tablet and smartphone designs average 25 with some design showing system savings as much as 36 Figure 4 represents the DPO power savings by comparing the backlight level with and without DPO Figure 4 DPO Power Savings Backlight Level w o DPO Backlight Level w DPO High Bacllight Strength Low Dark T T T T Ambient Light Level Lux 2011 QuickLogic Corporation PRELIMINARY www quicklogic com 5 QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A Visual Improvement VEE is set up in this mode to improve the viewing quality of the display to the best level possible by applying VEE strength as strong as possible While VEE does not create artifacts in the display content artifacts or noise present in the source display content will be amplified al
18. st framework code executes in a virtual machine Native libraries daemons and services written in C or C e Linux Kernel which includes drivers for hardware networking file system access and inter process communication As described earlier QuickLogic offers three individual software pieces for Android including veeapp apk MDDO Q1AutoAl apk and settings apk QlAutoAl apk and settings apk are installed in layer 1 and veeapp apk must be installed in layer 3 The system designer must provide access to drivers at layer 4 including the I C display backlight and ambient light sensor for proper operation www quicklogic com P R E LI M l NA RY 2011 QuickLogic Corporation QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A Contact Information Phone 408 990 4000 US 647 367 1014 Canada 44 1932 21 3160 Europe 886 2 6603 9848 Taiwan 86 21 5116 0532 China E mail info quicklogic com Sales America sales quicklogic com Europe sales quicklogic com Asia sales quicklogic com Japan sales quicklogic com Support www quicklogic com support Internet www quicklogic com Revision History Revision Date Originator and Comments A July 2011 Paul Karazuba and Kathleen Bylsma Notice of Disclaimer QuickLogic is providing this design product or intellectual property as is By providing
19. us Visual Enhancement Engine Application or Baseband Battery Level Processor _ gt QuickLogic Display Power Optimizer Mobile Display TSL25711FN Digital Ambient Light Sensor Sy TAOS How VEE and DPO Operate within a System VEE and DPO are contained PSBs within a QuickLogic CSSP solution platform The operation of the VEE and DPO technologies is as follows e The ambient light condition is determined through an ambient light sensor ALS gt Upon startup the CSSP requests the ambient light value Android reports all ongoing changes in ambient light to the CSSP through a QuickLogic software daemon that communicates to Android application program interfaces APIs Alternative method The CSSP can communicate directly with the ambient light sensor through I C to determine ambient light level Polling of ambient light data can be programmed at any interval on the CSSP www quicklogic com P R E LI M l NA RY 2011 QuickLogic Corporation QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A e Display backlight levels Upon startup the CSSP requests the display backlight level Android reports all changes to display backlight level to the CSSP through a QuickLogic software daemon that communicates to Android power manager where ambient light display backlight tables are typically stored Alternativ
20. ww quicklogic com 7 QuickLogic s Visual Enhancement Engine VEE and Display Power Optimizer DPO Android Hardware and Software Integration Guide Rev A To calibrate for manual brightness settings by the user VEE strength is calibrated for every ambient light and backlight condition in the auto backlight calibration table Table 2 as shown in Table 3 Table 3 VEE and DPO Manual Backlight Calibration Table Display Ambient Light Measured Levels Lux Backlight Levels 50 25 60 30 65 35 70 40 80 45 50 150 225 500 1 250 10 000 50 000 90 60 100 80 100 100 Not every value in Table 3 needs to be calibrated for but gathering as many as possible provides e Amore effective VEE that is a perfectly restored calibrated viewing experience e An optimized power savings scheme from DPO Software Implementation in Android QuickLogic has developed three distinct software pieces to implement these recommendations in the Android operating system e veeapp apk e settings apk e Q1AutoAl apk Mobile Device Display Optimizer VEEApp apk VEEApp is a Linux application with two modes command line and daemon It sits within the library level of Android above the kernel level see Figure 6 VEEApp communicates with the Android Power Manager to get updated ambient light and display backlight levels and communicates with the ArcticLink II VX solution plat
Download Pdf Manuals
Related Search