TIF transparency

[OldRadioGuy]

I have a photo-objects collection package that exports transparent objects only as a TIF file. Windows 7 shows the exported TIF file on my desktop as transparent, yet when I open the TIF file in PL 16, the transparency is lost.

Why does PL fail to support TIF transparency?

Bob

[Gerhard Huber]

where is the sample image?

Gerhard

[OldRadioGuy]

where is the sample image?

Gerhard

Gerhard, here is a composite screen cap showing examples. If you need me to send you the actual TIF file, let me know. Thanks.

Bob

[Gerhard Huber]

I need a sample TIFF.

Gerhard

[Gerhard Huber]

OK, I now got it.
The file has an incorrect "Extra Sample" tag. In TIFF files there is such a tag to show what information is in the extra samples. For alpha there should be 1 or 2, your file has 0.

Gerhard

[OldRadioGuy]

OK, I now got it.
The file has an incorrect "Extra Sample" tag. In TIFF files there is such a tag to show what information is in the extra samples. For alpha there should be 1 or 2, your file has 0.

Gerhard

Thanks, Gerhard, for the quick response.

For those following this thread and for the record -- the image originated from an old collection of photo objects dating back to the year 2000 (for Windows 95/98/2000 and Windows NT 4.0), and was saved to an external file via the photo objects package's internal software.

Despite the flawed coding, I was able to save the file as a TIF in another program and then open it in PL with the transparency. So, I at least have a way to use the image in PL without having to erase a background.



Thanks again, Gerhard and PL. Your response time to questions remains impressive!

Bob

[bkh]

OK, I now got it.
The file has an incorrect "Extra Sample" tag. In TIFF files there is such a tag to show what information is in the extra samples. For alpha there should be 1 or 2, your file has 0.

Perhaps it would make sense to import such extra sample layers as additioal greyscale layers (maybe set to "invisible")? Then the user can simply correct the problem by using the extra layer as a clipping layer or layer mask for the rgb layer.

Cheers,

Burkhard.

[greenmorpher]

Gerhard's provided a technical explanation, Bob, but it leaves the question hanging -- how is it that "another program" can open your pic with transparency and PhotoLine can’t? There must be some indicator of transparency for the other program to respond to. So will PhotoLine be fixed so it can respond to that same indicator and thus allow you (and the rest of us) to open such files correctly without having to resort to another program or to doing stuff like removing a while background?

Best regards

Geoffrey Heard
The Ad-Doctor-Online
http://www.ad-doctor-online.com

[bkh]

Gerhard's provided a technical explanation, Bob, but it leaves the question hanging -- how is it that "another program" can open your pic with transparency and PhotoLine can’t? There must be some indicator of transparency for the other program to respond to. So will PhotoLine be fixed so it can respond to that same indicator and thus allow you (and the rest of us) to open such files correctly without having to resort to another program or to doing stuff like removing a while background?

As Gerhard explained, the tiff file in question is badly formatted, and I doubt that there is any other non-standard indication regarding the extra layer. Instead, my guess is that the "other program" just regards an extra layer as transparency (which may well be wrong - for example, some slide scanners use it for an infrared channel, to provide information about dust and scratches). So I'd prefer PL not to treat additional layers as alpha channels automatically (but to add them as greyscale layers, as explained before).

Cheers,

Burkhard.

[Gerhard Huber]

So I'd prefer PL not to treat additional layers as alpha channels automatically (but to add them as greyscale layers, as explained before).

I will change the TIFF import this way.

Gerhard

[bkh]

So I'd prefer PL not to treat additional layers as alpha channels automatically (but to add them as greyscale layers, as explained before).

I will change the TIFF import this way./quote]
Great! Thanks!

Burkhard.

[greenmorpher]

Excellent -- that will give us choice according to the picture content. What about an option dialog Treat extra layers as transparency/treat extra layers as grayscale, which would come up only if PL detected the TIFF file as being non-standard?

Best regards

Geoffrey Heard
The Ad-Doctor-Online
http://www.ad-doctor-online.com

[OldRadioGuy]

... What about an option dialog Treat extra layers as transparency/treat extra layers as grayscale, which would come up only if PL detected the TIFF file as being non-standard?

That sounds like a good idea to me.

Bob

[OldRadioGuy]

... it leaves the question hanging -- how is it that "another program" can open your pic with transparency and PhotoLine can’t?

Not to linger on this issue, but if the coding is incorrect in the TIF file, why does Windows 7 show the poorly-coded image thumbnail as transparent on the desktop? When saved as a PLD, the same image or any image for that matter will not show as a thumbnail on the desktop of Windows 7 64-bit (only the generic PL icon).

Bob

[greenmorpher]

That's apples and oranges, isn't it Bob? The question is does a TIF saved out of PL show up with a thumbnail?

PLD format preview works fine on Mac OS X.6.6 . . . after I turned on Preview! It has a little frame round it which other previews don't, but that's no problem. Also a TIF saved out of PL shows a preview.

The joke is that I had been vaguely wondering why I had stopped seeing previews recently when I selected a file. Poking around testing this question, I discovered I had somehow turned Previews off! Probably happened when I clicked at random some time to wake up the sleeping computer or monitor.

Looks as though someone needs to click on the sleeping me!

Best regards

Geoffrey Heard
The Ad-Doctor-Online
http://www.ad-doctor-online.com