Problem Saving Images With a Transparent Background

[Bhikkhu Pesala]

I think we have spent enough time on this. If you cannot understand the replies already given, and check out the dialogue box options for yourself, then there is not a lot more we can do.

Find a friend who can sit with you and guide you through the process. It really is not at all difficult. You save the file and click on the white background to make it transparent.

[lwc]

And if you read what I wrote, it doesn't get transparent (even though it's just a white background from Paint that is expected to have just one shade)...

[Laurent]

Hi lwc,

After you have reported this thread to me, I read it. Honestly, Bhikkhu and others did their best to help you. Bhikkhu is right, the background of your JPEG image is not a uniform colour, but many slightly different ones. The one you choose as transparent colour becomes transparent, not the other ones.

Don't forget that saving your JPEG as a GIF decreases the number of colours and maybe the slightly different ones in the background are replaced by a unique one.

It seems to me you want IrfanView to consider that colours "similar" (in your mind) to the one you choosed as transparent also become transparent. But the way you want it to work is not the way it really works. You have to accept this.

If you consider IrfanView does not meet your needs, please use another program better for you.

Laurent

[lwc]

Laurent, all I'm saying is that JPG source is just one example of source (I never asked to put the word "JPG" in the subject of this topic). A default white background when you open up Microsoft Paint is just one shade and yet it doesn't get transparent.

[Bhikkhu Pesala]

A default white background when you open up Microsoft Paint is just one shade and yet it doesn't get transparent.

Yes it does. See my attachment. You keep on saying it doesn't work for you, but are unable to provide us with any evidence.

The GIF and PNG images that you attached to this post both have transparent backgrounds.

Open the attachment to my previous post in IrfanView and see what colour the background is. Change the IrfanView main window colour in Properties, Viewing, and reload the image. Now see what colour the background is.

The image was created in MS Paint, copied and pasted to IrfanView, then saved as a PNG with a transparent background.

[Mij]

lwc, I can also confirm that you can save a transparent color for a PNG in IrfanView.
It is very easy to be confused about colors though. I would recommend that you download Farbhexe which Frank has kindly posted in the IrfanPaint thread here. Using that little app you can move the cursor over the area that you want to save as transparent and check that it really is one single color. Look particularly at the R, G, B values to the left just above the color name.
There are useful tools in Irfanview too. Open Image> Information and look at the Number of unique colors that are in the image to see if that is as you expected. If you have paletted colors, as in a GIF or PNG image, then click on Image > Palette > Edit Palette to see what range has been provided for those unique colors to be selected from.

I created a simple red rectangle on a black background first in Microsoft Paint and saved as a PNG and a GIF. They behaved exactly as I expected (except that Paint saves an unnecessarily large palette). I then saved the PNG from IrfanView with the red rectangle selected as transparent and that worked fine too.

I did the same in CorelDraw which has fancy features like Color management and anti-aliasing to see if that made a difference. The PNG and GIF were the same as before (except that the Red color was changed by the Color management and a small red band of a different hue was created by the anti-aliasing). Saving with the red rectangle transparent also worked fine.

Now isn't that odd! The GIF saved by Paint which is definitely reported as a GIF on my computer is changed into a Jpeg by the Forum upload, but the GIF saved from CorelDraw remains a GIF. Perhaps there is more than meets the eye going on here.

Later: I see that the reason the Paint GIF could not be uploaded was that the size of a GIF is limited to 620x280 pixels on this forum and mine was a bit taller. That is a rather low limit isn't it? The file size was only just over 2Kb.

[lwc]

See my attachment.

Solved! Thanks for this phrase, I quickly realized the problems were double - my transparency option for PNG files somehow got turned off (or maybe the default was off in previous versions) and IE6 can't present transparent PNG files (this forum doesn't use the patch).

Now it works. Sorry for the confusion, but please realize that you can catch more flies with honey than with vinegar (thanks Mij).

You can close this issue now and let it rest in peace.