Solved

distance between two pixels using VB.

Posted on 2001-07-18
7
259 Views
Last Modified: 2010-08-05
Hi,
   I have a BW scanned image that is saved as a bmp, basically I want to figure out it's length by measuring the top-most black pixel and the bottom pixel.  How do I find these pixels?  I also would like to find the width at a certain number of inches, pixels, or whatever down the image.  How do I do this also?  I figure it would be easy if I started at the top left pixel and scaned row by row till I found a black one but I have no idea how to do this.  Can someone help me?

Thanks in Advance,
Aaron
0
Comment
Question by:Cide
7 Comments
 
LVL 22

Accepted Solution

by:
rspahitz earned 150 total points
ID: 6296056
Point Method
     

Returns, as a long integer, the red-green-blue (RGB) color of the specifiedpoint on a Form or PictureBox. Doesn't supportnamed arguments.

Syntax

object.Point(x, y)

--
Use a loop something like this:

for y=0 to Picture1.height
  for x=0 to Picture1.width
    if Picture1.Point(x,y) = vbBlack then
      msgbox "Found it at x,y= " & x & "," & y, vbokonly
      y = Picture1.height ' force exit of the row loop
      exit for
    end if
  next x
next y

0
 
LVL 8

Expert Comment

by:glass_cookie
ID: 6296575
Hi!

Here's a file over the net for you:

Download...
http://www.planetsourcecode.com/upload/ftp/CODE_UPLOAD7488762000.zip

Description: I just made a couple changes to this.I am new at programming so this is my first shot so i hope i don't blow it:) This program lets you open a picture file and it tells you the height and width of the picture in pixels. I think this would come in very handy in making webpages so you'll know the exact dimensions of the pic. If it is really useless let me know. Thx

That's it!

glass cookie : )
0
 
LVL 5

Expert Comment

by:KDivad
ID: 6297083
Note about rspahitz's code. Change the picbox's scalemode to pixels. It'll run about 225 (15x15) times faster that way. Also, you'll need a backwards loop to search up from the bottom. Same code, but with two changes:

for y=Picture1.height to 0 step -1

     y = 0 ' force exit of the row loop

KDL
0
Do You Know the 4 Main Threat Actor Types?

Do you know the main threat actor types? Most attackers fall into one of four categories, each with their own favored tactics, techniques, and procedures.

 
LVL 5

Expert Comment

by:KDivad
ID: 6297088
To get the width, just pick a row (second parameter of Point) to select points from and search across (inner For-Next loop). Then do the same on the same row but look backwards from the other end.
0
 
LVL 22

Expert Comment

by:rspahitz
ID: 6299282
Thanks, KDivad, I forgot about the "bottom" and "right" request.
0
 

Author Comment

by:Cide
ID: 6299479
Wow works like a charm thanks guys!

Kdivad thnaks additionally for your extra help, went so much faster with your "tweaks".  If you want some points I can put then on a sperate question just ask me.
0
 
LVL 5

Expert Comment

by:KDivad
ID: 6299608
rspahitz,
We all have to forget something sometimes. Gives the rest of us a chance to brag a bit. <grin>

Cide,
Don't worry about it. I may need your help someday.

Later,
KDL
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

Introduction In a recent article (http://www.experts-exchange.com/A_7811-A-Better-Concatenate-Function.html) for the Excel community, I showed an improved version of the Excel Concatenate() function.  While writing that article I realized that no o…
Since upgrading to Office 2013 or higher installing the Smart Indenter addin will fail. This article will explain how to install it so it will work regardless of the Office version installed.
As developers, we are not limited to the functions provided by the VBA language. In addition, we can call the functions that are part of the Windows operating system. These functions are part of the Windows API (Application Programming Interface). U…
Show developers how to use a criteria form to limit the data that appears on an Access report. It is a common requirement that users can specify the criteria for a report at runtime. The easiest way to accomplish this is using a criteria form that a…

757 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

21 Experts available now in Live!

Get 1:1 Help Now