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videomike | 9 years ago | 9 comments | 2,151 views

When I add a png file---either from Bixpack 7 or from my own stash---it acts as just another jpg. For example, the png file of a treble clef is white on a black box. I would espect to see only the white treble clef sign, not the black box. I cannot figure out what I need to do to make that happen. By the way, I want to place this treble clef sign over the top of a jpg I have already added to the show.




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Not all png files are transparent. It is perfectly normal for a png file to have a non-transparent background, like the treble clef sign of BixPack7 (jc_musicNote4.png).

If you want you can use a paint application like Photoshop to make the background of a picture transparent.

Here's a treble clef with a transparent background:

freestockphotos.biz...

michiel, 9 years ago


Thank you, Michiel. I posted a second, similar question a little while ago because I did not see this first question posted. Anyway, I don't understand why a file with a non-transparent background would be called a png file, assuming that the picture or text is only meant to be used without that same background. I can put it into Photoshop, work with it awhile, then save it with a transparent background as a png file; but if I am starting with a png file, that process seems redundant. Would it be possible to add to your collection some more png files with transparent backgrounds. That would be much appreciated. Thanks again for a great piece of software and all your help.

videomike, 9 years ago

There is nothing wrong with a PNG without transparency. This is perfectly all right. Very common and nothing to worry about.

I think the treble clef is rendered with additive blending. This way the black parts are transparent because the RGB values of black are (0,0,0) and if you add nothing it's invisible. To experiment: create a new picture layer, select the treble clef, click on the CHANGE EFFECT...,. button and select the NotLightened_Additive.fx effect.

michiel, 9 years ago


Thanks, Michiel. I found that new effect in BixPack 7, but when I applied it the whole png file disappeared---no treble clef and no black background. I also applied the opposite effect (subtractive) with the same result. Since I last wrote to you I found another png file that will work and already has a transparent background. But if I could understand the workaround for the file that has a non-transparent background, that would be great. Thank you again for your help.

videomike, 9 years ago

Hi Videomike,

Sugestion,

Create a new blank BluffTitler file by selecting FILE -> NEW SHOW from the top menu.

Load your picture and with the picture layer selected press F9,

Your treble clef should be listed in the very top box as the first texture, make sure 'try to keep textures and effect matched' is UNCHECKED, and select NotLightened_Additive.fx as the effect from your files in the effects folder.

Put something in the background, like a new text if not there already, and with the picture layer for your music note selected, switch to position from the dropdown box under 'All Layers' 'All Keys' and move the bottom slider left and right.

This should allow your picture to move along the Z axis back and forth and through the other object showing no background present as the black will be omitted (I believe this is a commonly used way to fake transparency because it works so well and no messing about creating new versions of files)

Please note: This effect relies on lighting in your scene, if you have no point light intensity set, or other light settings such as the colour being set to black - you will see nothing.....

Hope this helps...

Regards

Bob

Pixelpanther, 9 years ago


Additive blending is by no means a "workaround" or a way to "fake" transparency.

It is a very popular, very powerful effect. It is used by almost all particle layers.

It is called additive because it adds the RGB (red, green,blue) values of itself to the background. For this reason black is transparent because its RGB values are zero. No matter what colour the background is, if you add 0 it will remain the same.

The NotLightened_Additive.fx is not a "new" effect or exclusive to BixPack 7. Instead it comes with the installer. You can find it in the Media/Effects folder.

Other FXs also use additive blending. Examples are:
-Compositions/ReflectiveFloor_CubeMapDDS_Additive.fx
-Compositions/ReflectiveFloor_ReflectionMap_Additive.fx
-Flare.fx

Additive blending works best with a white shape on a black non-transparent background.

Yes, this is exactly why the music note pictures of BixPack 7 are white shapes on a black non-transparent background!

Here's more info about the flare effect:

outerspace-software.com...

michiel, 9 years ago


More about effects in the user guide:

outerspace-software.com...

michiel, 9 years ago


Hi Michiel,

Sorry I was trying to put it in simple terms for Videomike, I do agree it is a completely useful effect in its own right as are the other FX, just achieves the result I think he was looking for so tried to explain it perhaps a little too simply....

My apologies if that seemed to be a generalisation it was purely to try and help Videomike achieve what he was trying to do. Perhaps my wording could have been better....

Regards

Bob :)

Pixelpanther, 9 years ago


On the contrary, I think you explained it very well.

michiel, 9 years ago


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