367036 - Transparent background of images shows up as black when printed

Status: RESOLVED FIXED

(Core :: Graphics, defect)

Description

[Bill Gianopoulos [:WG9s]]

When you print a web page that contains images with transparent backgrounds, the image background is always printed as black.

The page displays fine in print preview.  I have noticed this on various sites and with various printers.  The problem does not occur with Firefox 2.0.0.1.

The Yahoo! home page listed above is an example of a page with such an image.

Comment 1

[Bill Gianopoulos [:WG9s]]

This testcase:

https://bugzilla.mozilla.org/attachment.cgi?id=216496

from bug 331941 also exhibits the issue.

Comment 2

[Bill Gianopoulos [:WG9s]]

(In reply to comment #1)
> This testcase:
> 
> https://bugzilla.mozilla.org/attachment.cgi?id=216496
> 
> from bug 331941 also exhibits the issue.
> 

Hmm, oddly this testcase fails with Firefox 2.0.0.1 also, so perhaps there is an additional issue effecting .ico files.

However the http://www.yahoo.com prints correctly under Firefox 2.0.0.1, yet under current trunk, the Yahoo! logo image incorrectly prints with a black background.

Comment 3

[Bill Gianopoulos [:WG9s]]

Attachment: Test PNG image that illustrates the issue

Printing the attached PNG image with current trunk shows the issue.  This image prints correctly with Firefox 2.0.0.1.

Comment 4

[Andy Boze]

Attachment: PDF showing black background

In addition to transparent backgrounds in images showing up as black when printed, background of text appears black when printed. I used a "print to PDF" drive to create the attached PDF, but the Web page prints identically on my Canon  iP4200 printer. The original Web page is at http://waltonfeed.com/grain/faqs/ivb.html . Note in the PDF that the text and the palm tree graphic both have black backgrounds when they should be transparent.

Comment 5

[Vladimir Vukicevic [:vlad] [:vladv] (needinfo me, slow to respond)]

Attachment: only allow blits from screen DCs, never from printer DCs

This should fix it, though I'm not super happy about the patch.. but the chances of there being a printer driver that supports bitblt from its DC isn't very good, so this should be safe.

Comment 6

[Vladimir Vukicevic [:vlad] [:vladv] (needinfo me, slow to respond)]

Checked in.

Comment 7

[Jeff Walden [:Waldo]]

Printing reftest, perhaps?

Comment 8

[Bill Gianopoulos [:WG9s]]

And we have an automated way to print a page and scan it in and compare it with a previously printed and scanned image?

Comment 9

[Jeff Walden [:Waldo]]

No; <http://lxr.mozilla.org/mozilla/source/layout/reftests/printing>.  I have no idea whether that would work here or not, but if it doesn't, there's surely another way to test this, even if it's harder to make it work.

Comment 10

[Eli Friedman]

(In reply to comment #9)
> <http://lxr.mozilla.org/mozilla/source/layout/reftests/printing>.

That wouldn't work; that renders to the screen.  (It's primarily meant for testing page breaking.)

Comment 11

[Patrice Gauvin]

I did a test in the Gran Paradiso (beta 5) version and transparent background are not black but white.. Png tranparency seem still to be a problem !

Comment 12

[Eli Friedman]

(In reply to comment #11)
> I did a test in the Gran Paradiso (beta 5) version and transparent background
> are not black but white.. Png tranparency seem still to be a problem !

Please file a new bug with a testcase.

Comment 13

[Ryan VanderMeulen [:RyanVM]]

This is back in full force now that Cairo 1.5 has landed on the trunk.

Comment 14

[Daniel Brooks [:db48x]]

Yea, it looks like the fix got reverted when Vlad next upgraded Cairo, though it was before cairo 1.5

Comment 15

[Vladimir Vukicevic [:vlad] [:vladv] (needinfo me, slow to respond)]

Reapplied patch.  Missed it somehow when doing the cairo upgrade, sorry!

Comment 16

[aaron]

Attachment: Example of alpah transparency printing black on Firefox 2.0.0.11

This example uses alpha transparency instead of index transparency. The transparent area always prints solid black. Tested using Firefox 2.0.0.11 .

Comment 17

[aaron]

All tests of the index transparency were performed over the network using the following printers:

HP LaserJet 4000n
HP LaserJet CP4345xs
HP LaserJet CP3505dn

I noticed this bug is listed as resolved fixed, but it seems that might have been a bit premature, I hope someone is still watching this bug.

Comment 18

[Leanan]

I, too, hope that someone is still watching this bug, as I am experiencing behavior that appears to be exactly this.

It appears to be fine on my linux box, but on my WinXP box, I am getting a black bar around the image.

There are probably other ways to get this, but this is how it is occurring for me.  I have tested some of the images attached to this and it appears to not be happening with the first image (turtle) but it is occurring with the last image (A)

STR:

1) Create a page with a canvas on it. 
2) Use toDataURL to convert the canvas to an image
3) Display the image URL, do a print preview and notice all looks fine
4) Print the image and notice the black bars/background/etc that should not be there

Expected: The printed version of the image should look like the print preview with no black showing
Observed: The printed version has a black box around the image, which is different than the print preview which does not show this.

Extra info:
WinXP Pro SP2
FF 2.0.0.14

As you can see, the behavior appears to be this bug.  If it is not, let me know and I'll gladly open a new one.

Comment 19

[Martijn Wargers (dead)]

Leanan, this was about a bug that was happening on trunk (Firefox 3), so what you are experiencing with Firefox 2 is certainly not this bug.

Comment 20

[Dan Schaefer]

Thunderbird 2.0.0.23 is producing the same result. Viewing the email and print previewing the email appear normal. Printing the transparent PNGs result in black backgrounds.

Extra info:
Win XP Pro