how to calculate vertical and horizontal projection histogram for an image

Hi guys I am doing a project on offline signature recognition and verification. I hove done till thining process of an image. Now i need to calculate vertical and horizontal projection histogram for this image. Can any body suggest me some code for this. Thanks.

Answer 1

[Jakob Sørensen]

Let me see if I get this right... You want to make a histogram, but instead of having a color intensity as bin numbers, you want to use the different rows/columns for bins?

[Jyoti]

Hi Jakob

Thanks for the cosideration to my question.You are actually getting it right.here i want to use different rows/columns for bins.so that i can calculate horizontal and vertical projection histograms and then i also need to find the maximum horizontal and maximum vertical projection.

[Rageeni sah]

Hello there, I want to know that when we plot horizontal/vertical histogram of an image, what information can we get from the histogram??

[Image Analyst]

I don't think he meant histogram. He probably just doesn't know the the proper terminology. If you sum an image across or down you get the profile or projection, not histogram. If you have a binary image of text, then the histogram of the projections doesn't really tell you much of any use . But by looking at the projection you can determine where lines of text start and stop. Start your own thread and post your own image if you want specific help.

Answer 2

[Rujal]

can anyone please help me to create feature vector of vertical and horizontal projection histogram. please give me a matlab code on [e-mail] . . . Thanks in advance

[Image Analyst]

Not sure what that means. A projection of data along a dimension, and a histogram (frequency distribution) are different things. Start your own question and attach your data and what you'd like to get from it.

Answer 3

[Walter Roberson]

sum(YourImage,1)  %vertical projection
sum(YourImage,2)  %horizontal projection

This assumes YourImage is binary. If it isn't, you need to define what you mean by "projection" of multiple colors.

Answer 4

[si sam]

to Jyoti : did you get it?

Answer 5

[Paramesh]

I got it.Nice.

[si sam]

i would be thankful if can you please show me how you drew vertical and horizontal histograms?

[Walter Roberson]

Use histogram() or hist(), or use bar()