To test the processing element in MECA & correct the
fault processing element.
To design a BIST circuit for processing elements.
Self detection and self correction.
• Joint Video Team (JVT).
• Motion Estimation Computing Arrays (MECA).
• Integrating MECA into a system-on-chip (SOC) design
has become increasingly important for video coding
• MECA performs up to 50% of computations in the entire
• For a commercial chip, a video coding system must
introduce Design For Testability (DFT), especially in an
• These DFT approaches can be divided into three
1. Ad Hoc (Problems).
• Among these techniques, BIST has an obvious advantage
in that expensive test equipment is not needed and tests
are low cost.
• The extended techniques of BIST are built-in self-
diagnosis(BISD) and built-in self-repair (BISR).
Current and Reference Pixels:
• In a Video Sequence for 1Sec of time 64-images are
• Current and Reference pixels are the two successive
images of the Video Sequence.
• Current Pixel is the present image displayed.
• Reference Pixel is the next image to be displayed.
• These two Pixels are Considered as the inputs.
• The Current and Reference pixels are carried forward to
• Here the Coder is used to convert the image into the Code
• The codes are stored in the two different memory slots.
• In coder 2 coder modules are used to generate test code.
• Processing element calculates the sum of absolute
differences between current pixels and reference pixels.
• And then the two images are compressed into one image.
• Motion Estimation of the two pixels are done here.
• The Output of Processing Elements is taken as the input for
• Detection of errors formed in the processing elements is
• Syndrome Decoder is used to detect the error bit position.
• Selector has two inputs.
1. Processing Elements
• Here the exact error bit position is found by comparing the
• Input to the corrector module is the output of the selector
module that needs to be corrected.
• The corrector architecture consists of LUT(Look Up Table)
and 12 multiplexers.
• Aerospace/Defense, Automotive, Banking, Computer,
Healthcare, Networking, and Telecommunications.
• Motion Estimation used in MPEG-4 Multimedia
Applications and H.264/AVC video coding Standards.
• Motion Estimation in Space Science.
• Tracking of a person in a video sequence
• Better fault coverage, since special test structures can
be incorporated onto the chips
• Shorter test times if the BIST can be designed to test
more structures in parallel.
• Lower cost of test.
• Less no. of gate counts.
• More reliable.
• Easier customer support.
• Power Consumption is Low.
• Additional silicon area and fab processing requirements for
the BIST circuits.
• Additional pin requirements.
• Reduced access times.
• It uses more memory.
Timing required for Motion Estimation will be reduced.
The input to the MECA is 8-bit data. It also can be
extended to higher volume of data.
BIST can used in Flash memory type of Systems.
Built-in Self-Detection/Correction Architecture for
Motion Estimation Computing Arrays is the project that is to
decrease the errors in the video sequence and make the video
more reliable to watch & Also estimates the tracking of a
person & object.