Transparency color selection

[mikiqex]

Hi, long time ago i suggested cool feature from IrfanView - transparency color selection, before saving GIF, PNG, ICO etc. Answer was it's good improvement, but in beta i wasn't able to find it, so i'd like to remind it

It's the same or zoomed picture in special dialog window and using mouse you can choose a color to be transparent. It's much faster than trying what color in pallete is the right one.

It's also possible to use this feature instead "Edit Colormap" dialog window to select transparent color (or whatever).

Thanks.

[xnview]

Hi, long time ago i suggested cool feature from IrfanView - transparency color selection, before saving GIF, PNG, ICO etc. Answer was it's good improvement, but in beta i wasn't able to find it, so i'd like to remind it

It's the same or zoomed picture in special dialog window and using mouse you can choose a color to be transparent. It's much faster than trying what color in pallete is the right one.

It's also possible to use this feature instead "Edit Colormap" dialog window to select transparent color (or whatever).

And why Edit colormap is not good for you ?

[Drahken]

The problem wuth the colormap method is that you have to know exactly what color you want to make transparent. If there is only one shade of green and that's what you want transparent, it's easy. If there are a dozen shades of green, it could take a dozen tries to find the right one. In the other program, you click on a portion of the image itself to choose the color, this way you know it's the right one without having to retry a dozen times.

[xnview]

In the other program, you click on a portion of the image itself to choose the color, this way you know it's the right one without having to retry a dozen times.

I don't understand, for GIF transparency you need only 1 transparency index???

[Drahken]

You have only 1 transparent color, but the problem is in trying to locate which color. If you have an image that's red, white, and blue and you want the blue sections transparent it's easy. What if your pics has several shades of blue? In order to figure out which one is the one you want to be transparent, you may well have to try a dozen times.

Take this pic for example: http://allspark.net/cypherswipe/trans-test.png There are dozens of near-black entries, trying to find the palette entry which will change the black background to transparent is hit & miss. You might get the right one, or you might just make one of the shadows in the middle of the image transparent. With the other method, you could simply click on the background and it would automatically choose the right palette entry.

[mikiqex]

The problem wuth the colormap method is that you have to know exactly what color you want to make transparent. If there is only one shade of green and that's what you want transparent, it's easy. If there are a dozen shades of green, it could take a dozen tries to find the right one. In the other program, you click on a portion of the image itself to choose the color, this way you know it's the right one without having to retry a dozen times.

Exactly, that's it

[xnview]

The problem wuth the colormap method is that you have to know exactly what color you want to make transparent. If there is only one shade of green and that's what you want transparent, it's easy. If there are a dozen shades of green, it could take a dozen tries to find the right one. In the other program, you click on a portion of the image itself to choose the color, this way you know it's the right one without having to retry a dozen times.

Exactly, that's it

Oh, you want to select transparent index directly on the picture??

[mikiqex]

The problem wuth the colormap method is that you have to know exactly what color you want to make transparent. If there is only one shade of green and that's what you want transparent, it's easy. If there are a dozen shades of green, it could take a dozen tries to find the right one. In the other program, you click on a portion of the image itself to choose the color, this way you know it's the right one without having to retry a dozen times.

Exactly, that's it

Oh, you want to select transparent index directly on the picture??

Yes, it's much faster than trying what shade is the right one

And in IrfanView it was (optionally) like another dialog window during "saving procedure", so you didn't forgot to set the transparent color. IMO this solution si more user friendly (at least for me )

[herr_k.]

Oh, you want to select transparent index directly on the picture??

is this in progress/evaluated?
i would like to see that too.

btw,where is the palette editor for changing a color to transparent?

[herr_k.]

the "edit colormap" is always greyed out, so i cannot choose it. or is this only possible with 256 color gifs.
is there another way to find out on which entry in the colormap a certain color is, so i can save it as transparent?

btw i am also never able to choose "true colors" when saving ia gif - why not?

[xnview]

the "edit colormap" is always greyed out, so i cannot choose it. or is this only possible with 256 color gifs.
is there another way to find out on which entry in the colormap a certain color is, so i can save it as transparent?

To edit the colormap, your picture must have a colormap (4< <256 colors)

btw i am also never able to choose "true colors" when saving ia gif - why not?

GIF is only able to save maximum of 8bits

[herr_k.]

aha.

btw i am also never able to choose "true colors" when saving ia gif - why not?

GIF is only able to save maximum of 8bits

hm, i just wondered, because there is a greyed out "true colors" option in the gif-savedialog when choosing colors..

[Clo]

—> Pierre

Hello !

…GIF is only able to save maximum of 8bits…

• That's not quite true, you might have written :
“The programmes are only able to save GIF as 8 BPP”.
- There was a discussion a while ago, showing that the original specs. don't limit the GIF to 8 BPP, with a sample…
- I can't find out it again now, but maybe… Mr. Librarian, please ?

KR
Claude
Clo

[XnTriq]

Bad GIF implementation

[Clo]

—> XnTriq

Hello !

• Thanks ! It's indeed the right thread !

KR
Claude
Clo