Vukota Pekovic

Automatic functional TV set failure detection system

Enormous technological innovation in recent years has put a great challenge upon manufacturers in consumer electronics industry: how to efficiently and accurately verify the functionality of a product handed to a customer. To address this problem, we propose a fully automated system for functional failure detection in TV sets. In the proposed framework, the automatic assessment of TV set functionality is performed by processing captured images of the TV set under inspection and the captured images from the reference TV set (which is considered to be with no functional failures). A new algorithm for image similarity is proposed and incorporated in the system for evaluating the difference between the tested image and the reference one, in respect to specific degradations that can occur in TV sets. The similarity detection algorithm is a full-reference intra-frame video quality assessment scheme, which is based on spatially local mean square error and variance between the reference and the tested image. Based on the similarity detection, an acceptance decision for the TV set functionality is made. The proposed embedded system for automatic TV functional failure detection includes (i) central control unit through which the testing methodology is carried out: The TV set under inspection is fed by the test video signals defined by the (ii) specified test-case-scenario, while the picture is simultaneously captured from the tested TV set and compared by the (iii) proposed similarity detection algorithm to the reference one, for the same type of TV set. Finally, the results are stored in the (iv) data base for TV set debugging purposes. The usability and effectiveness of the proposed methodology has been experimentally evaluated and detailed analysis of the results has been reported. The proposed similarity detection algorithm has shown to be superior to the other state-of-the-art image quality assessment algorithms in terms of detecting TV picture degradations (such as picture misalignment, illumination change, aliasing, blurring, etc.) in captured images from TV set, under the methodology which incorporates defined test-case-scenario.

On the Effectiveness of the System Validation Based on the Black Box Testing Methodology

With the advancement of technology in recent years, effective fault diagnosis became a necessity to verify the performance and ensure the quality of complex systems. In this paper, an original verification methodology for complex consumer electronic devices is presented. Verification of the system which consists of hardware (integrated circuit) and corresponding software within a flat panel TV set is in the focus. Proposed methodology provides reliable functional failure detection using the concept of black box testing. Further, the approach is fully automated, improving the reliability and speed of failure detection. The methodology effectiveness has been experimentally evaluated and the analysis results have been reported.

Quality assessment of digital television picture based on local feature matching

This paper presents a novel, full-reference image quality measurement method for video quality assessment in television systems. Particularly, the proposed metric targets the problem of automatic assessment of digital picture degradations. The performance of proposed algorithm has been evaluated on different image sequences with various distortions of interest. The results show that the proposed scheme for quality assessment outperforms other image quality measures: PSNR, SSIM and VIF in terms of more efficient quality inspection based on local feature matching as well as robustness against various distortions such as luminance or contrast change, negligible picture misalignment, etc.

Test management and test execution system for automated verification of digital television systems

This paper presents a test management and test execution system created to be used during process of Digital Television System automated verification and testing. Designed test environment is able to handle product requirement data, test cases management data, test execution planning process, test system configuration and execution of manual, semiautomatic and automatic test cases during verification and testing process. The part of the system is also Reporting and Monitoring module responsible for results evaluation and presentation. Realized test environment is set of independent modules which will together create automated test Enterprise solution.

Stimulation board for automated verification of touchscreen-based devices

This paper presents preliminary results of the research with the goal of designing a system for automated verification of touchscreen-based devices. The proposed system is based on electrical stimulation of touch-screens, as opposed to the mechanical stimulation nowadays used in such systems. Stimulation is performed by the FPGA-based stimulation board which touches the screen with the long conductor connected to the ground. It simulates the electrical field distortion similar to the distortion induced by introducing the finger to the electrical field of the touch-screen. The long conductor is disconnected from the screen electrically, with the use of a transistor. Controlling the on/off state of the transistor controls whether the conductor touches the screen or not. Preliminary results show that such electrical stimulation of touch-screens is possible, but further research is needed to improve the reliability of the stimulation board.

Automatic Black Box Testing of television systems on the final production line

The current verification methodologies on the final production line in digital television industry require a significant amount of manual work in connecting and disconnecting the television set to and from signal sources and verifying the correctness and quality of image shown on the TV screen. This manual work slows down the production and increases the cost of a final production line. This paper proposes an automatic system which will perform all required verification steps on the final production line such that manual work will be minimized, speed of the production will significantly increase and the cost of the final production line will decrease. The proposed final production line uses the camera to capture the image shown on the TV screen which improves the earlier solution with the grabber to allow verification of the image quality as seen by the user. The proposed system consists of: (1) TV set being verified, (2) camera to capture the content on the TV screen, (3) signal generator, (4) test monitoring system and (5) PC which runs the algorithm for extraction of the TV screen content and comparison with the referent content. The proposed algorithm uses the block-based normalized cross-correlation to compare captured and referent content. The proposed testing methodology divides the verification on the final production line in three steps: (1) setup phase, during which the TV set is brought and connected to the signal sources and test monitoring system, (2) execution phase which captures the content on the TV screen and runs the PC algorithm and (3) test report phase which reports the pass/fail result of the test in the test monitoring system. The experimental results of the block-based comparison method show a better sensitivity to small differences than the non-block-based method. The time required for verification step increased by a factor of 5 when using the automatic approach on the final production line instead of a manual one.

Framework for automatic testing of Set-top boxes

This paper proposes framework based on Black Box Testing methodology which is used for automatic testing of Set-top boxes (STB). Proposed framework for automatic testing can be used for functional testing, regression testing, performance testing and stress testing of STB. Complete system for automatic testing consists of web tool responsible for requirement and test management along with stand-alone application for execution of automatic test cases in form of scripts written in Python programming language. Paper gives an overview of the whole system for automatic testing along with list of framework functions and their usage for creating automatic test cases.

Protocol independent remote controller emulator for automated testing of multiple DTV/STB

This paper proposes a new scheme for DTV/STB remote controller emulator (RCE), which enables automatic control of the DTV/STB devices under test from independent test hardware/software platform. Specifically, the proposed RCE sets the DTV/STB device in particular state within the automatic functional verification system during the test procedure. Besides, it has the ability to record the remote controller (RC) commands sent to the device (history of commands sent by the user), which can be used for debugging the DTV/STB devices when their functionality failure is detected. The proposed RCE is neither dependant on the RC nor the DUT.

User-driven automatic test-case generation for DTV/STB reliable functional verification

In recent years Digital TV receivers (DTV) and Set- Top Boxes (STB) have been advancing in terms of new functionalities they offer to the end-users. This has mainly been triggered by the appearance of new multimedia formats and applications needed to be adequately handled by the DTV/STB. In such complex system within the environment consisting of wide range of non-interactive as well as interactive applications and services for television, internet, gamming, healthcare, surveillance, etc., efficient and reliable DTV functional verification becomes highly necessary and challenging task. Since efficient DTV testing is considered as one of the most important issues for the reduced time-to-market, its optimization is of crucial importance to the DTV manufacturing process. Having in mind the end-users as the main target of the DTV, optimal test generation process must also include estimated usage-profiles in addition to the pre-defined DTV designed specification. This is especially important considering new emerging multimedia technologies for DTV which are not yet fully standardized and evaluated, and which exact employment (from the point of end-users) is not known in advance. In this paper we propose a novel approach for user driven test-case generation that would enable adequate and efficient testing of the DTV/STB in different development stages before reaching the market, i.e., the end-users. The proposed user driven approach provides optimal test-case generation in terms of both test execution time and adequacy according to the real end-user DTV functional DTV operation and quality of experience (QoE). This is obtained by incorporating a novel design and selection scheme for test-cases generation based on the modeled end-users most required functional operations on the DTV/STB under test and its expectations of it.

Video freezing detection system for end-user devices

This paper proposes a novel system for video frame freezing detection, which can be easily attached to different multimedia end-user devices for video quality monitoring. The system is implemented on commercially available multi-core1 platform in real-time.2