Trying to add photos of people in .tiff format

transparent
image
import
background

#1

Hello

I’m trying to take photographs of people to my models. I take a .tiff format photo, with no background, and place it in the scene, adjusting the size to make it correct. But when I render the scene, there’s a white background to the photo, meaning a while rectangle around the person.

Can anyone tell me how to get rid of the white rectangle?

Thanks!


#2

Sounds like a rendering thing. Perhaps the best option would be to trim around the people to get rid of the excess surface area. You can explode the image after import and make it a component. Edit the component and trace around the edges of the person and erase the outside edges.

Or use TIG’s Image Trimmer to do it automatically. It’s available in his SKM Tools extension. See this also.


#3

You need to Edit the image-file [Gimp or PhotoShop].
Make it a PNG format.
Flatten it.
Add an Alpha Transparency Layer.
Use the magic-wand to select all of the white background and delete it.
Auto-crop to ensure the minimum dimensions of the imported Image.

Either explode it into a face and manually draw around the transparent parts and delete them, or as DaveR says install/use my ImageTrimmer tool to do that automatically for you…
Please carefully read the instructions on its use, and ensure that the JAR file-type is owned by Java, so that the tiny executables needed to do the image processing are runnable…


#4

Thank you for your help. I should have mentioned that I’m using Photoshop Mix for iPad to trim the images. I send the image to my Macbook and use Preview to save the image as a png file. I tried with two different images to import them into SketchUp and then use the Trimmer plugin, but the result is the same as if I hadn’t used Trimmer. I get the image with a large white background and it renders with that background.

What am I doing wrong?

Thanks again


#5

Are you adding a Transparency [Alpha] Layer to the PNG and deleting the white background as i outlined ?
Please attach a simple PNG image with which you are having issues, and I’ll look at it…
At the moment it’s guesswork…


#6

Hello

I don’t know how to add a Transparency Layer to the PNG. As I mentioned, I take an image and trim it in Photoshop Mix on my iPad and export the jpeg to Preview on my Macbook. Preview lets me export it as a PNG.

Are you familiar with Photoshop Mix and Preview? If so, do you know how to add a Transparency Layer?

Sorry for my ignorance, but at least I’m willing to learn!
And thank you for your willingness to explain.


#7

Preview has a magic-wand to remove the background of tiff’s or png’s


#8

Thanks @john_drivenupthewall, I don’t have MAC access at the mo…
It may be important to ‘flatten’ and add the alpha-channel otherwise ANY even slightly transparent pixels in the PNG get zapped by ImageTrimmer.
If you bring a PNG with a transparent background into SketchUp as an Image you should be able to look through it and NOT see any background.
The downside is it casts a rectangular shadow.
To have a useful shadow you need to explode it into a single face [inside a component-definition] and draw around its outline and delete any unwanted parts; or simply use ImageTrimmer to automate that all for you…


#9

@Fred_
can you export tiff or png from PMix?

can you upload an example of an image [even if only a jpg] ?


#10

Thank you @john_drivenupthewall!

I used Preview to “extract an image” and it worked! I’m uploading the image I made in the rendering program (wierd, I know, but I was experimenting!) and it worked fine - shadows that follow the correct outline, etc.)

Thank you for your help!


#11

Is this what you want?

-Gully


#12

Yes, actually it is. I had trimmed the animal, leaving half of it off to save time. I wanted just the outline of the animal with shadows that follow the contours of the animal. I know, it’s a very strange, but the effect is what I wanted.


#13

Okay. This was pretty basic. In PaintShop Pro I used the Background eraser tool to “erase the background” (turn it transparent). I’ve gotta think PhotoShop has the same tool. Then I simply saved it to .png, specifying that existing transparent areas be saved as alpha-channel transparency.

Feel free to use the copy I uploaded, although I suspect this is just a low-res copy of your original image.

-Gully

We live in a post-Lewis Carroll culture; hence a partially invisible cat is no big deal.

-G


#14

@john_drivenupthe wall: as far as I know, Photoshop Mix will only allow
exports of .jpg files.

What image do you want me to upload?

Here’s one that I mande ready to use in SketchUp after going through the
process you all described. The best part is that since it’s a transparent
image, you can use it reversed as well!


#15

Just to point out the difference.
Your transparent png casts no shadows, exploded it casts a rectangle, trimmed casts the profile.