Measuring items in a photo...

[Moze]

Not sure where else to post this.

Can anyone recommend software (and the procedure) to obtain dimensions of an object if you know the dimensions of another object in the photo?

ie: I have a photo of a set of channel letters. I need to determine the approximate dimensions of the letters (HxW). There's a 4" drip edge that I can use to scale from.

Years back, I thought I remember doing this in Corel Draw. I thought you could "measure" something in a photo, specify the true dimension (4" in the case of the drip edge, above), then use that same dimension line to measure something else....the dimension would increase as you increased the length of the line, but it would keep the scale the same based on your previous input of 4".

Make sense?

 

[MikePro]

i input photos into illustrator, to which I have the CadTools plug-in from www.hotdoor.com.
scale the photo to match the dimensions of your known object, and as long as the photo was taken squarely and straight-on, you're golden. (sometimes within a certain amount for error, to which I usually round-up slightly)


quick-fix is what my boss does all the time, thinking he was saving me from too much work:
using the copier, keep copying the graphic at different scale increases until a known measurement is able to be identified on an engineer's scale, and then obtain the rest of the dimensions you need with the same scale.

 

[GAC05]

This is an easy one in Corel.
Put a rectangle around the object you know the size of.
Power clip the photo into the rectangle
Resize the rectangle proportionally to the known size.
Unclip the photo - it should be the correct size now.
You could then use dimensions to measure the resized object but it is easer to just draw a box around it & check the size of the box.

wayne k
guam usa

 

[MikePro]

you can do that?
not bad.
whenever I clip a photo, scale tools read the object as it's overall dimension (outside of clipped portion).

 

[PRS Bryan]

Once I use photo shop to correct any angles, I just use an engineers scale and calculator.

Measure the known object divide the number of "units" into the known length. This gives you an objective length per unit.

Then measure the unknown object in "units" multiply the number of "units" with the objective length per unit.

It is confusing the first few times but it is quick, cheap and easy once you get the hang of it.

 

[GAC05]

you can do that?
not bad.
whenever I clip a photo, scale tools read the object as it's overall dimension (outside of clipped portion).

Works in Corel, Illustrator has a funny way of handling clipped objects. Takes some getting used to.
In Draw the clipped contents are isolated to the border of the clipping object & you have to drill down into the clip to edit them.

wayne k
guam usa

 

[fresh]

In Corel, I make a box around the object of known size. For example, I have a 12x2" magnet we use for scale on vehicles.

On the photo the box is 3.25x0.54. You can use a calculator to determine the size you need to scale it up to...

12/3.25= 3.692 or 2/0.54 = 3.703 (I always use the 12" dimension for scaling though)

Multiple that number by 100, and you get the % of scale to increase the image - 369.2%

It takes no time at all if you have a calculator handy.

I should learn the clipping mask thing, but this way works well for me.

 

[James Burke]

I always use the largest item (of known size) in the photo. Your measurements will be more accurate when you scale from larger objects, rather than something small.

I use Illustrator, and I have a template art board that has several rectangles of the most common sizes we use. It also contains some vector images of old school drafting "tools" such as a 30-60-90 and a 45-90 triangle.

All I do is import the photo into the template file and do a scale reduction (or enlargement) of just 1%. I then use the CTRL + D keys (transform again) and CTRL Z (undo) to quickly scale the image smaller or lager. I can usually accurately scale a photo in less than a minute with no calculations....just match the photo to the correctly sized rectangle.

 

[Joe Diaz]

This is an easy one in Corel.
Put a rectangle around the object you know the size of.
Power clip the photo into the rectangle
Resize the rectangle proportionally to the known size.
Unclip the photo - it should be the correct size now.
You could then use dimensions to measure the resized object but it is easer to just draw a box around the it & check the size of the box.

wayne k
guam usa

The Process we use is similar but without using the powerclip feature.
http://coreldraw.com/blogs/coreldra...e-week-designing-your-sign-work-to-scale.aspx

I think the main reason is we were doing this before there was a Powerclip feature in DRAW, so it's kind of a force of habit. But I may have to try your way.

 

[Moze]

Thank you for all of the responses!

 

[J Hill Designs]

draw shape to known shape

double click ruler

go to scale

input actual size of shape = actual size of object

viola whole image is scaled

 

[bob]

In Corel, I make a box around the object of known size. For example, I have a 12x2" magnet we use for scale on vehicles.

On the photo the box is 3.25x0.54. You can use a calculator to determine the size you need to scale it up to...

12/3.25= 3.692 or 2/0.54 = 3.703 (I always use the 12" dimension for scaling though)

Multiple that number by 100, and you get the % of scale to increase the image - 369.2%

It takes no time at all if you have a calculator handy.

I should learn the clipping mask thing, but this way works well for me.

So does unscrewing a light bulb by holding onto the bulb and turning the lamp.

Do it exactly as Wayne K describes.

No calculators, no long division, just the ability to draw a rectangle. It works in Corel and It also works in Flexi.

This method is so handy that if I have to take a picture of something I'll set a standard 16"x24" framing square somewhere in the picture, parallel and square to the plane of the photo. Bring the picture into Corel or Flexi, draw a rectangle around the framing square, power clip or mask the photo into the rectangle, and make the rectangle 16"x24". Un-mask the picture and it should, pretty much, be full scale.

 

[Marlene]

I do this all the time in Omega. I don't know about Corel but in Omega thre's a measuring tool. I just increase the photo to 800 inches or so and measure what I know then increase or decrease until what I know measures correctly. what I'm working on screen is life size so everything I do is to scale. no real math involved. for a truck or a small post and panel type sign the photo usually goes from 150" to 300" large building from 800" to 1000" or more. you get a feel for it after a while so you aren't screwing around much to go to life size

 

[Moze]

Thank you for the additional responses.

I swear Corel had a tool where you could draw a line, specify what dimension it was, and if you changed the length of that line, it would increase or decrease the dimension accordingly.

Anyway, I'll try the methods given - thank you!

 

[Jester1167]

Macromonster.com has a corel plugin that is either free or inexpensive that works well for scaling an image. It works in x5 not sure about x6. http://macromonster.com/index.php?mod=descr&id_desc=91&keyword=scaling&Submit=Go

 

[QuickSilver2605]

We've been thinking about getting this software around my shop. Looks pretty interesting. http://www.stickyard.com

 

[bob]

We've been thinking about getting this software around my shop. Looks pretty interesting. http://www.stickyard.com

Were the instructions, iterated multiple times in this thread, for scaling in Corel, Flexi, whatever using rectangles and objects of known size unclear? Perhaps not in your native language? Too vague? Concepts of 'rectangle' and 'masking' too complicated?

Stickyard is right up there with the top ten all time unnecessary things and wastes of money in modern history. It does nothing that you can't do without it.Just as easily if not easier.

 

[iSign]

Just having an after hours beer with a competitor/friend, and logged in on my phone because he got a client call... so I didn't read anything in this thread, but I picked this thread to post about the most expensive mistake in my sign career...

I used the 36" doors in a pic, to interpolate the size of the wall surface, & the other wall features (granite tiles) and design my sign to fit in an aesthetically pleasing manner, with respect to the different colors of granite...


What I failed to account for was the granite wall surface was closer to the camera, because there was a sort of outdoor foyer where you would walk into this opening in the wall, to a door that was set back 3 or 4 feet from the wall...

Anyway, I had subbed out $5000,00 with of work on this $11k sign, before I realized it was too big... so I still have all that $5000 worth of wrong size materials... but I had to start over once I discovered the mistake in my calculations...

I had chosen to interpolate my sign size from the photo, instead of actually going out to measure the sign, out of pure lazyness ...assuming if measure later (literally right around the corner)

 

[phototec]

Not sure where else to post this.

Can anyone recommend software (and the procedure) to obtain dimensions of an object if you know the dimensions of another object in the photo?

ie: I have a photo of a set of channel letters. I need to determine the approximate dimensions of the letters (HxW). There's a 4" drip edge that I can use to scale from.

Moze, you say you want to measure an image in a photograph, I do this all the in Photoshop, there are several ways to do this. The RULER tool is located under the magnifying glass, and will measure the width or height of a know object, then use your calculator to find the percentage of magnification that would make the image in the photo the full size. Now you can measure any object in the image and multipy by the X factor and you will know the full size dimension.

I also just enlarge the photo to full size once I know one actual dimension, then you don't need the calculator anymore, everything will be the actual size so you just use the ruler tool.

Here is a video showing some of the many ways to measure in Photoshop.

[video=youtube;CrBBNq7hXEo]http://www.youtube.com/watch?v=CrBBNq7hXEo[/video]

I also have CADTools for Illy, it works great if you want to place the photo into illy. You can use one of many different standard scale settings and enlarge the photo to the scale you want to use, once you do this you can now measure any part of the photo and CADTools will give you the exact dimension.

[video=youtube;OVlqnHHmgGw]http://www.youtube.com/watch?v=OVlqnHHmgGw[/video]

 

[John Butto]

Free app for IPhone or IPad:
RulerPhone free-photomeasuring

 

[Terremoto]

This is an easy one in Corel.
Put a rectangle around the object you know the size of.
Power clip the photo into the rectangle
Resize the rectangle proportionally to the known size.
Unclip the photo - it should be the correct size now.
You could then use dimensions to measure the resized object but it is easer to just draw a box around it & check the size of the box.

wayne k
guam usa

Brilliant! Used this method half a dozen times in the last two days.

Dan