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#1 Re: Help Me ! » distance from camera to object » 2012-07-12 15:28:02

Hy thanks Bob:)

Well i tried to solve that.

if you see this figure :http://i1069.photobucket.com/albums/u472/tina12354/anglefind-1.png

then cos(60) = base /hypo
       1/2      = 100 / y
       y = 200 cm


and sin(60)     = perpendicular / gypo
      sqrt(3) /2 = x / 200
      sqrt(3)*100 = x
      x = 173 cm.

Is it correct ?
So in think distance from cam to object is 173 cm.
Please correct me if i am wrong .
thanks

#2 Re: Help Me ! » distance from camera to object » 2012-07-12 05:18:10

hmm yes you can say focal length .

#3 Help Me ! » distance from camera to object » 2012-07-12 05:07:55

model
Replies: 8

Hy guys ,

I want to find distance from camera to object .
A picture is given in this link: http://i1069.photobucket.com/albums/u472/tina12354/anglefind.png

Could any one please help me how to find distance from camera to object .
thanks

#4 Help Me ! » Graph of electricity » 2012-06-25 00:29:57

model
Replies: 6

Hy guys,

Can any one please explain me this graph :

http://i1268.photobucket.com/albums/jj562/ridasana/writingtask1.jpg


I did not understand graph by unit of electricity .
Could any one please explain me . thanks

#5 Re: Help Me ! » Need help in understanding haar wavelet transformation » 2012-06-11 06:28:42

Hy Bob:

Thanks .
Actually i need to understand it mathematically .
Check out this link: http://robotics.stanford.edu/~scohen/lect02/lect02.html#eq:dil-scaling-j

Hy Bob, I need your help to understand it mathematically .
I am not capturing sense of Haar wavelet basis in figure
Could you please help me thanks

#6 Help Me ! » Need help in understanding haar wavelet transformation » 2012-06-10 17:22:27

model
Replies: 4

hy guys ,

I am trying to understand haar wavelet transform.

I have 3 images given below .

1. http://i1268.photobucket.com/albums/jj562/ridasana/2.jpg
2. http://i1268.photobucket.com/albums/jj562/ridasana/3.jpg
3. http://i1268.photobucket.com/albums/jj562/ridasana/1-1.jpg

My problem is i do't understand figure in 3rd link.
I did not understand that how did he consider values of B , V , H and D.
Could any one please help me to understand it. Thanks

#7 Help Me ! » convert to scientific notation » 2012-05-27 19:20:30

model
Replies: 2

how  can i convert 1,228,000 in scientific notation ?

Could any one please help me thanks

#8 Help Me ! » Rotation in Homogeneous coordinate » 2012-04-07 05:14:51

model
Replies: 4

Hy All,

I am not understanding this eq in link : http://www.cs.mtu.edu/~shene/COURSES/cs3621/NOTES/geometry/geo-tran.html

, rotating a line Ax + By + C = 0 about the origin a degree brings it to a new equation:

(Acosa - Bsina)x' + (Asina + Bcosa)y' + C = 0

How did he get the equation ? ? ?

Also how did he use this equation  in the above link .
as shown in figure this : http://imageshack.us/photo/my-images/853/2drottran.jpg/

How did he combine it to make it translation and rotation ?

Please help me to understand  it thanks

Could any one tell me ?
thanks

#9 Help Me ! » Homogeneous Coordinates » 2012-04-07 04:15:40

model
Replies: 0

Hy all,

Question : Homogeneous Coordinates System

In this link : http://www.cs.mtu.edu/~shene/COURSES/cs3621/NOTES/geometry/homo-coor.html

Its  said that

Without the use of homogeneous coordinates system, it would be difficult to design certain classes of very useful curves and surfaces in computer graphics and computer-aided design

Which meant if we convert Cartesian coordinate to Homogeneous system then we could handle infinity.

Ok then let say we have two point (x ,y) , by converting to homogeneous we will get x/w , y/w then let say w = 0 then it would be infinity . then how  are we dealing with infinity here ?
How are converting infinity . its same as cartesian form.  but yes if the eq is in polynomial form then we could handle infinity .

How is it homogeneous then ?

#10 Re: Help Me ! » Area and perimeter of shapes » 2012-03-18 20:32:24

Let say i have square like as shown in this link,.
http://www.mathsisfun.com/geometry/perimeter.html

In the square we have 4 sides . that meant perimeter is 3 + 7+ 3+ 7 = 15
My question is : what is the area of that square in the link .

In my understanding ,i think that square have 3 columns and 7 rows  which mean the area is 3*7  = 21 pixels is area of that square .

Am i right ?
Please help me to understand it .thanks

#11 Help Me ! » Area and perimeter of shapes » 2012-03-18 20:18:54

model
Replies: 2

Hy all ,

I have two question about area and perimeter .

So first Area :

* Area is the number of pixels within a region.
* And Area can be find as quadtree . but how ?
Say  i have an image 10 * 10 . how  can we find area by representating an image in form of quadtree ?

* How can we find area using polygon vertices ?

Second about Perimeter :

Perimeter is the number pixels in the boundary  of  shape .

let  say i have an square of 4*4 . What's the perimeter of it  ?
and let say i have triangle
like
*
**
***   in the stared triangle, What is the perimeter ?
Please help me to understand ti .
I need to know about these  as soon as possible until tomorrow .
Expecting a good response thanks

#12 Help Me ! » Fourier transform and log polar coordinate system » 2012-03-11 15:49:18

model
Replies: 1

IS Fourier transform also  called log  polar coordinates system ?

#13 Help Me ! » automated mean and deviation for color normalization » 2012-03-05 01:06:52

model
Replies: 2

How to calculate automated mean?

what does mean by deviation to color normalization ?

#14 Help Me ! » Degree and movement condition statement understanding » 2012-02-27 18:19:44

model
Replies: 0

if thumb moves 0 to 90 degree and back two times fast.

What does mean by 2 times fast ?

Does it mean like

if(thumb move to 0 to 90 and thumb.x 2 and thumb.y*2)  ???

#15 Re: Help Me ! » Please elaborate the given statement. thanks » 2012-02-27 03:35:43

bobbym wrote:

Hi model;

Any more to that quote?

no , just that is the statement.

#16 Help Me ! » Please elaborate the given statement. thanks » 2012-02-27 01:35:27

model
Replies: 3

Statement:

"delete the vertex whose distance is less than 10 pixels when comparing with next vertex .then we will get one single point. "

What does it mean ?

Does it mean like

Say i have point A and point B

if(distance of A and B < 10) then delete which vertex A or B.?

What does mean by the above quoted statement ?

#17 Re: Help Me ! » Count the number of fingers of hand » 2012-02-25 20:03:47

John E. Franklin wrote:

i dont understand how you get all the points in place in the first place.  Who put down the 3 colored points?
Is the hand flat on to the camera?  Are you neglecting the vanishing point or perspective and using the image as is?

Yes, I found convex hull of my hand contour or have image..
and those circles are convexity defects presented on hand.
And yes its hand from live video. and video is a sequence of images.

#18 Re: Help Me ! » Count the number of fingers of hand » 2012-02-22 21:40:19

I have hand center  point . and points from convex hull like start , end and depth points .

I need to find the hand radius . How can i do that ?

Please share ideas thanks

#19 Help Me ! » Count the number of fingers of hand » 2012-02-16 19:52:12

model
Replies: 4

Hy  All.

This is an image of convex hull of hand plus defect points : http://imageshack.us/photo/my-images/818/convexhullanddefect.png/

where
blue circles : start point
red circles : end point
green circles : depth points.

I want to define the finger counter from defect points .
Does any one have any idea to get the number of fingers .
if yes then please share ideas,
thanks

#20 Help Me ! » find the other point on the circle with center point and radius of cir » 2012-02-15 03:34:13

model
Replies: 2

Hy ,

if we have radius of a circle and center value .
then how can we find the other point on the circle ?

#21 Re: Help Me ! » Bayes' Theorem » 2012-02-12 17:47:17

bobbym wrote:

Hi model;

I think you meant by this is area of point A, right ?

#22 Re: Help Me ! » Bayes' Theorem » 2012-02-11 21:08:38

bobbym wrote:

Hi model;

Unless we can get the problem down to something like post #6 we will not be able to say anything about the probabilty.

I will draw you a diagram that will hopefully explain what we need.

hmm ok i am waiting for your diagram then . 
and yes thanks for helping me. smile

#23 Re: Help Me ! » Bayes' Theorem » 2012-02-11 00:19:02

well initial location of  my hand is 0 when there is no hand appear  in the video  but when hand appear any where in the video then location will appear .  Hy  please consider #6 for my work as i shown in the image.

#24 Re: Help Me ! » Bayes' Theorem » 2012-02-10 23:53:09

Hy,

my image area is : 76800

and hand area is : 4592

you can see in this image as link :  http://imageshack.us/photo/my-images/823/imgoy.png/

And now tell me what info do we need to get the probability of my hand as a point A ?

#25 Re: Help Me ! » Bayes' Theorem » 2012-02-10 23:35:45

bobbym wrote:

If you were to draw an imaginary rectangle around the area where Point A could be placed where would it be?

hmm hold on. lemme post  here total image size in form of rectangle area . and a point A(i-e hand) with its coordinates x  and y .  ok

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