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Motion vectors Vs. Static Blocks Vs. Dynamic Blocks.

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hmodi Posts: 27	Posted 22:18 May 27, 2011 \| Question: 1) We identify the motion vector (MV) by comparing the target image and reference image. We obtain this MV by best matching blocks. It I understand correctly this best matching blocks are not necessarliy same int the content. So how do we differentiate between static block and the blocks that are static but content is different? For e.g. in following MV blocks 2,1; and 2,2 are dynamic. And other blocks are static. But block 2,0 is static and content is different. [0,0] [0,0] [0,0] [0,0] [0,0] [0,0] [0,0] [0,4] [0,-1] So when we remove the dynamic block again we compare each block for the content? Can please somebody clarify? Question 2) What is the search area to find the closest static block during the removal of dynamic block? Surrounding the dynamic block or the whole image? Question 3) In Extra credit Application 2, the query image is also from the IDB2 database or any image? From the output given in HW it looks like any image! Is that correct? Thanks and Look forward for reply!
eykang Posts: 95	Posted 07:44 May 30, 2011 \| 1) Based on the mv information only, it is possible that a certain block with mv (0,0) corresponds to a part of moving object or a certain block with mv non-(0,0), e.g. color changes due to light, corresponds to a part of static background. No further processing is required in this case, Allow your program to be erroneous if this happens. 2) This is a program design question. The term "Closest" defines where to search. You can search the whole image but is it necessary when you are interested in finding the closest block? 3) The query image is selected from IDB2.

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hmodi

Posts: 27

Posted 22:18 May 27, 2011 |

Question: 1)
We identify the motion vector (MV) by comparing the target image and reference image. We obtain this MV by best matching blocks. It I understand correctly this best matching blocks are not necessarliy same int the content. So how do we differentiate between static block and the blocks that are static but content is different? For e.g. in following MV blocks 2,1; and 2,2 are dynamic. And other blocks are static. But block 2,0 is static and content is different.

[0,0]   [0,0]   [0,0]
[0,0]   [0,0]   [0,0]
[0,0]   [0,4]   [0,-1]

So when we remove the dynamic block again we compare each block for the content?
Can please somebody clarify?

Question 2)
What is the search area to find the closest static block during the removal of dynamic block? Surrounding the dynamic block or the whole image?

Question 3)
In Extra credit Application 2, the query image is also from the IDB2 database or any image? From the output given in HW it looks like any image! Is that correct?

Thanks and Look forward for reply!

eykang

Posts: 95

Posted 07:44 May 30, 2011 |

1) Based on the mv information only, it is possible that a certain block with mv (0,0) corresponds to a part of moving object or a certain block with mv non-(0,0), e.g. color changes due to light, corresponds to a part of static background. No further processing is required in this case, Allow your program to be erroneous if this happens.

2) This is a program design question. The term "Closest" defines where to search. You can search the whole image but is it necessary when you are interested in finding the closest block?

3) The query image is selected from IDB2.