transparency images raster

[Fulvio Romano]

Good morning.
do not ask me why mad ...I have to insert some raster images in a 2007 autocad design. the images represent a small object, but they are quite extensive because they must also understand the elements of alignment with the design. When I put it on the drawing I get a white pouch as big as the image.

is it possible to have an alpha channel command to say "all that is white does not exist, make me transparent"?

I read something about the property "transparency" which however has no effect. even if I turn the .jpg into .png and the remount as raster.

ideas?

don't whip me.. .

 

[Fulvio Romano]

Alternatively, is it possible to "draw" a piece of the image so that all that remains becomes invisible?

 

[GP.]

must be an image saved with transparency.

 

[Giuseppe Mauro]

Is the image in colour or white? (not grey, pure white)

you can crop part of the image with _imageclip

image transparency makes it "similtrasparente" (not function as the alpha channel, it only allows you to see the vectors below)

If the image is pure white, I'll tell you how to get an alpha channel thing.

 

[Fulvio Romano]

Wow...funge!

It's in color.

the jpg does not take transparencies, then I made a png. but at that point I should erase all the pictures and reimport the png...

instead... I closed the dwg, renamed the pngs as jpg and... magic!

evidently finds the associated name, but opens the real format, not that of the extension.

 

[Giuseppe Mauro]

instead... I closed the dwg, renamed the pngs as jpg and... magic!

Good boy!
You obviously discovered undocumented behavior of autocad.

I was drunk! :smile:

 

[GP.]

e' a colori.

In fact, transparence also works on color images, though in autocad is documented for bitonals.

The last ones, in addition to the transparency of the background color, have the possibility to change the color of the first floor.

 

[PlannerRoad]

...instead... I closed the dwg, renamed the pngs as jpg and magic!

evidently finds the associated name, but opens the real format, not that of the extension.

I have to try it!!!! :smile:

 

[Fulvio Romano]

Good boy!
You obviously discovered undocumented behavior of autocad.

I have to try it!!!! :smile:

definitely the cover of the images is not made by autodesk but is a cots library. the cots library, if done well, reads the file header and behaves accordingly, does not trust the extension. the extension exists for winzoz systems; under unix and linux is a convenience for the user, but the operating system completely ignores it, analyzing only the content of the file.

then, autocad knows that he has to read the pippo.jpg file, finds it and passes it to the library, which opens it, understands that it is a png and acts accordingly. All line.

It was about losing two minutes and trying instead of taking for granted that the pc is "stupid".

In fact, transparence also works on color images, though in autocad is documented for bitonals.

The last ones, in addition to the transparency of the background color, have the possibility to change the color of the first floor.

I actually erased in gimp background, saving png with transparent background. I didn't do anything in autocad. I don't know if it was clear.

 

[GP.]

...saving the png with transparent background. i didn't do anything in autocad. i don't know if it was clear.

i understood perfectly. . :smile: