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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

hmm yes you can say focal length .

**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

**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

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

**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

**model**- Replies: 2

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

Could any one please help me thanks

**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

**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 ?

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

**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

**model**- Replies: 1

IS Fourier transform also called log polar coordinates system ?

**model**- Replies: 2

How to calculate automated mean?

what does mean by deviation to color normalization ?

**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) ???

bobbym wrote:

Hi model;

Any more to that quote?

no , just that is the statement.

**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 ?

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.

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

**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

**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 ?

bobbym wrote:

Hi model;

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

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.

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 ?

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