bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

This bug report will be sent to the Free Software Foundation,
not to your local site managers!
Please write in English if possible, because the Emacs maintainers
usually do not have translators to read other languages for them.

Your report will be posted to the bug-gnu-emacs@gnu.org mailing list
and the gnu.emacs.bug news group, and at http://debbugs.gnu.org.

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug.  If you can, give
a recipe starting from `emacs -Q':

  emacs -Q
  (image-type-available-p 'png) => t
  C-x C-f some-file.png RET => no image displayed, only an empty box.

Does anyone else using the precompiled Windows binaries of v23.2.91
(from alpha.gnu.org) see this problem?

A binary I compiled myself from the stock v23.2.91 sources shows PNG
images just fine, with the same image libraries.

Sean, did you build the binaries differently from the previous pretest
(23.2.90)?  It does show PNG images on the same machine with the same
image libraries.

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
d:/usr/emacs/etc/DEBUG.


In GNU Emacs 23.2.91.1 (i386-mingw-nt5.1.2600)
 of 2010-12-11 on 3249CTO
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (4.4) --no-opt --cflags
 -Ic:/imagesupport/include'

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: HEB
  value of $XMODIFIERS: nil
  locale-coding-system: cp1255
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
( i m a g e - t y p e - a v a i l a b l e - p SPC ' 
p n g ) C-j <up> <left> <left> <backspace> <backspace> 
<backspace> s v g <right> C-j M-x r e p o r t - e m 
<tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

Load-path shadows:
None found.

Features:
(shadow sort mail-extr message ecomplete rfc822 mml easymenu mml-sec
password-cache mm-decode mm-bodies mm-encode mailcap mail-parse
rfc2231
rfc2047 rfc2045 qp ietf-drums mailabbrev nnheader gnus-util netrc
time-date mm-util mail-prsvr gmm-utils wid-edit mailheader canlock
sha1
hex-util hashcash mail-utils emacsbug tooltip ediff-hook vc-hooks
lisp-float-type mwheel dos-w32 disp-table ls-lisp w32-win w32-vars
tool-bar dnd fontset image fringe lisp-mode register page menu-bar
rfn-eshadow timer select scroll-bar mldrag mouse jit-lock font-lock
syntax facemenu font-core frame cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
case-table epa-hook jka-cmpr-hook help simple abbrev loaddefs button
minibuffer faces cus-face files text-properties overlay md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process multi-tty emacs)

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

>   emacs -Q
>   (image-type-available-p 'png) => t
>   C-x C-f some-file.png RET => no image displayed, only an empty box.

Using the binary created by Sean for the pretest, I get:

(image-type-available-p 'png) => nil

And when I visit a .png file I see text coding.

HTH - Drew

In GNU Emacs 23.2.91.1 (i386-mingw-nt5.1.2600)
 of 2010-12-11 on 3249CTO
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (4.4) --no-opt --cflags
-Ic:/imagesupport/include'

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: "'Sean Sieger'" <sean.sieger@gmail.com>
> Date: Thu, 23 Dec 2010 07:29:35 -0800
> 
> Using the binary created by Sean for the pretest, I get:
> 
> (image-type-available-p 'png) => nil

Do you have one of the PNG DLLs installed that are mentioned in
image-library-alist?

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> > (image-type-available-p 'png) => nil
> 
> Do you have one of the PNG DLLs installed that are mentioned in
> image-library-alist?

No.  (BTW, that variable is apparently now obsolete.)

Or rather, how would I know?  Where is the variable/function that tells me which
image DLLS are installed?

And shouldn't we be delivering such DLLs with Emacs?

And where are the instructions that explain where to get such DLLs and what to
do with them?  Does that "installing" require compiling etc. C sources, or just
putting some DLL files in some directory?  What tools does a (Windows) user need
to "install" the DLLs?

I haven't found any info about this in the Emacs manual, but maybe I'm not
looking well enough.  I tried `i image'(...), but saw nothing about what to do
to make Emacs images-enabled.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: <7716@debbugs.gnu.org>, <sean.sieger@gmail.com>
> Date: Thu, 23 Dec 2010 09:36:55 -0800
> 
> > > (image-type-available-p 'png) => nil
> > 
> > Do you have one of the PNG DLLs installed that are mentioned in
> > image-library-alist?
> 
> No.

Then that's why you get nil.  In your case, you cannot expect to have
PNG images displayed as images.

> (BTW, that variable is apparently now obsolete.)

Not in Emacs 23, which is what this bug is about.

> Or rather, how would I know?  Where is the variable/function that tells me which
> image DLLS are installed?

There isn't one, I think.  You could use image-search-load-path to see
if Emacs finds something (e.g., map it over the corresponding part of
image-library-alist).  Not sure why would you need that, though.

> And shouldn't we be delivering such DLLs with Emacs?

There are licensing issues with some of them.  We distribute the XPM
library, which is the minimum required for displaying the tool-bar
icons in color.  It should be downloadable from the same place where
you get the precompiled binaries.

> And where are the instructions that explain where to get such DLLs and what to
> do with them?

See nt/INSTALL (search for "image").

> Does that "installing" require compiling etc. C sources, or just
> putting some DLL files in some directory?

The latter; see nt/INSTALL.

> What tools does a (Windows) user need to "install" the DLLs?

Nothing but bare hands.

> I tried `i image'(...), but saw nothing about what to do to make
> Emacs images-enabled.

That's because they are enabled by default, if Emacs can find the
necessary support libraries.  PBM is built into Emacs, and the XPM
library is available together with Emacs.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

Eli Zaretskii <eliz@gnu.org> writes:

    Sean, did you build the binaries differently from the previous pretest
    (23.2.90)?  It does show PNG images on the same machine with the same
    image libraries.

I did not copy libXpm.dll to /bin.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

Eli Zaretskii <eliz@gnu.org> writes:

    Do you have one of the PNG DLLs installed that are mentioned in
    image-library-alist?

libXpm.dll is in /bin of each binary distribution---weekly build,
pretest or release that I've built and only ever compiled with version
3.5.8 of that library, um, just not the 23.2.91 pretest.

Sorry for the hassle.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

Sean Sieger <sean.sieger@gmail.com> writes:

    Eli Zaretskii <eliz@gnu.org> writes:

        Sean, did you build the binaries differently from the previous pretest
        (23.2.90)?  It does show PNG images on the same machine with the same
        image libraries.

    I did not copy libXpm.dll to /bin.

But isn't that why I configure with `--distfiles
c:/imagesupport/bin/libXpm.dll'

Shoot.  Either way, sorry.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: Sean Sieger <sean.sieger@gmail.com>
> Date: Thu, 23 Dec 2010 13:37:56 -0500
> Cc: 
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
>     Sean, did you build the binaries differently from the previous pretest
>     (23.2.90)?  It does show PNG images on the same machine with the same
>     image libraries.
> 
> I did not copy libXpm.dll to /bin.

XPM images are not the issue here; PNG images are.  And I have all the
necessary image DLLs on that machine anyway (I copied them to the bin
directory where emacs.exe lives).

Can you try the same binary you uploaded as 23.2.91 pretest on your
machine, and see if it displays PNG images?

Thanks.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

Eli Zaretskii <eliz@gnu.org> writes:

    > From: Sean Sieger <sean.sieger@gmail.com>

    > I did not copy libXpm.dll to /bin.

    XPM images are not the issue here; PNG images are.  And I have all the
    necessary image DLLs on that machine anyway (I copied them to the bin
    directory where emacs.exe lives).

(I cannot say it is blissful being as limited as I am.)  Sorry I wasn't
reading closely ... um, nope, didn't build any differently.

    Can you try the same binary you uploaded as 23.2.91 pretest on your
    machine, and see if it displays PNG images?

Yep.  And nope, I only have the headers on my system---no compiled png
libraries.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> > And where are the instructions that explain where to get 
> > such DLLs and what to do with them?
> 
> See nt/INSTALL (search for "image").

Where is nt/INSTALL?  I see the name "nt/INSTALL" referred to in the INSTALL
file of the installation directory (emacs), but I see no subdirectory `nt' at
any level, and no other `INSTALL' file than the one at top level.  And the
top-level INSTALL file is not much help - it says nothing about where to find
the "nt/INSTALL", "nextstep/INSTALL", etc. files.

> > Does that "installing" require compiling etc. C sources, or just
> > putting some DLL files in some directory?
> 
> The latter; see nt/INSTALL.

I would like to.  Where is it?

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

"Drew Adams" <drew.adams@oracle.com> writes:

    > The latter; see nt/INSTALL.

    I would like to.  Where is it?

There should be an /nt in your Emacs-24 that you get from
alpha.gnu.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

>     > The latter; see nt/INSTALL.
> 
>     I would like to.  Where is it?
> 
> There should be an /nt in your Emacs-24 that you get from
> alpha.gnu.

You mean a folder named `nt'?
I don't see one.  And search doesn't find one.

This is true of each of the Emacs-24's I have downloaded, both those you post
each week and the two pretests.  It is also true of the Emacs 23 releases.

What am I missing?

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[David De La Harpe Golden]

On 24/12/10 00:40, Drew Adams wrote:

> You mean a folder named `nt'?
> I don't see one.  And search doesn't find one.
>
> This is true of each of the Emacs-24's I have downloaded, both those you post
> each week and the two pretests.  It is also true of the Emacs 23 releases.
>
> What am I missing?
>
>

I  don't see a folder named nt or the nt/INSTALL file in either
http://alpha.gnu.org/gnu/emacs/windows/emacs-20101220-bin-i386.zip
or
http://alpha.gnu.org/gnu/emacs/windows/emacs-20101220-barebin-i386.zip

However, I do see a README.W32, which is (I presume) a copy of 
nt/README.W32 in the source tree.

But nt/INSTALL is AFAICS instructions on building and installing w32 
emacs from source anyway [1], README.W32 is the instructions on 
installing the binary distribution (the .zip) [2], and README.W32 does 
discuss image library dependencies. [3]

So I sorta doubt that nt/INSTALL belongs in the .zip.

There is also an nt/README in the source tree with different information 
to nt/INSTALL and nt/README.W32, it documents the nt directory, and may 
not belong in the .zip [4]

[1] nt/INSTALL in source tree
"""
Here are the concise instructions for configuring and building the
native Windows binary of Emacs,
"""

[2] nt/README.W32 in source tree, README.W32 in the .zip.
"""
This README file describes how to set up and run a precompiled
version of GNU Emacs for Windows.
"""

[3] nt/README.W32 in source tree, README.W32 in the .zip.
"""
Emacs can also support some other image formats with appropriate
libraries.  These libraries are all available as part of GTK, or from
gnuwin32.sourceforge.net.  Emacs will find them if the directory they
are installed in is on the PATH.
"""

[4] nt/README in source tree
"""
This directory contains support for compiling and running GNU Emacs on
Windows NT, Windows 95, and their successors.
""""

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: Sean Sieger <sean.sieger@gmail.com>
> Date: Thu, 23 Dec 2010 15:23:21 -0500
> Cc: 
> 
> (I cannot say it is blissful being as limited as I am.)  Sorry I wasn't
> reading closely ... um, nope, didn't build any differently.

That's strange, because the binary of the previous pretest shows PNG
images.

>     Can you try the same binary you uploaded as 23.2.91 pretest on your
>     machine, and see if it displays PNG images?
> 
> Yep.  And nope, I only have the headers on my system---no compiled png
> libraries.

Well, could you perhaps install at least one of them and see if PNG
images get displayed?  Thanks.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: <7716@debbugs.gnu.org>, <sean.sieger@gmail.com>
> Date: Thu, 23 Dec 2010 13:18:18 -0800
> 
> > > And where are the instructions that explain where to get 
> > > such DLLs and what to do with them?
> > 
> > See nt/INSTALL (search for "image").
> 
> Where is nt/INSTALL?

Sorry, I forgot you don't have the source tree.

In the binary distribution, you have the same information in the file
README.W32 that lives in the top-level directory of the Emacs tree.
Except that the 23.2.91 pretest doesn't have it.  (Sean, what
happened?)  But you should be able to find it in the previous pretest,
23.2.90.

Alternatively, use the Savannah interface to browse the repository at
http://git.savannah.gnu.org/cgit/emacs.git/tree/.

> And the top-level INSTALL file is not much help - it says nothing
> about where to find the "nt/INSTALL", "nextstep/INSTALL",
> etc. files.

It should be obvious that "nt/INSTALL" refers to a file INSTALL in the
nt subdirectory.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: Sean Sieger <sean.sieger@gmail.com>
> Date: Thu, 23 Dec 2010 18:24:59 -0500
> Cc: 
> 
> "Drew Adams" <drew.adams@oracle.com> writes:
> 
>     > The latter; see nt/INSTALL.
> 
>     I would like to.  Where is it?
> 
> There should be an /nt in your Emacs-24 that you get from
> alpha.gnu.

I don't think binary distributions include the nt subdirectory, nor
should they.  But they should include README.W32, which is absent in
23.2.91 (it is present in 23.2.90).  This is some snafu in preparation
of the binary distribution, I guess; please look into it.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> Sorry, I forgot you don't have the source tree.
> 
> In the binary distribution, you have the same information in the file
> README.W32...

> It should be obvious that "nt/INSTALL" refers to a file INSTALL in the
> nt subdirectory.

Well it was, but there is no nt/ folder (as I said).

BTW, README.W32 refers to "nt/INSTALL in the src distribution" but it does not
say what the "src distribution" is or where to find it.

Before I got your mail, Sean pointed me off list to where GnuWin32 is, so I
downloaded the setup files and ran them.  I hadn't read README.W32, but I just
guessed at the setup file names based on their descriptions.  The only one I
missed at first was the dependent one, zlib.

Installing the DLLs made it possible to display maybe 5% of the images I tested
with.  I can display a few of the JPG and GIF files, and one TIFF file.  I
cannot display most of the JPG and GIFF files and one TIFF file (I only had two
TIFFs to test with).  I cannot display any PNG files.  By "cannot display" I
mean that what gets displayed is only a 1 cm x 1 cm thin black box (empty) on a
white background.

So something is still wrong/missing.

I downloaded all of the image setup executables and ran them, which put all of
the required DLLs in a folder that I then added to my PATH.  These are the DLLs
I have:

glut32.dll
jpeg62.dll
libimage.dll
libpng3.dll
libpng12.dll
libpng13.dll
librle3.dll
libtiff3.dll
libungif4.dll
zlib1.dll

AFAICT, that should be all I need.

(In the same folder are lots of *.exe and other files.  There are also several
sibling folders.  I put only the bin folder in PATH (it is the one with the
DLLs.)

HTH.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@Oracle.COM>
> Cc: <7716@debbugs.gnu.org>, <sean.sieger@gmail.com>
> Date: Fri, 24 Dec 2010 08:03:28 -0800
> 
> Installing the DLLs made it possible to display maybe 5% of the images I tested
> with.  I can display a few of the JPG and GIF files, and one TIFF file.  I
> cannot display most of the JPG and GIFF files and one TIFF file (I only had two
> TIFFs to test with).

Please report that as a separate bug, and attach one image file of
each kind that you cannot display.

> I cannot display any PNG files.  By "cannot display" I
> mean that what gets displayed is only a 1 cm x 1 cm thin black box (empty) on a
> white background.

That's the bug I reported.  Can you do that in the 23.2.90 pretest?

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> Please report that as a separate bug, and attach one image file of
> each kind that you cannot display.

Will do.

> > I cannot display any PNG files.  By "cannot display" I
> > mean that what gets displayed is only a 1 cm x 1 cm thin 
> black box (empty) on a
> > white background.
> 
> That's the bug I reported.  Can you do that in the 23.2.90 pretest?

I see the same problem in both 90 and 91 pretests (and the latest Windows
binary, from 12/20).

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: <7716@debbugs.gnu.org>, <sean.sieger@gmail.com>
> Date: Fri, 24 Dec 2010 08:47:43 -0800
> 
> I see the same problem in both 90 and 91 pretests (and the latest Windows
> binary, from 12/20).

Something's not right with your image DLLs, then.  I think.  I'm quite
sure that the 90 binary worked for me.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

Eli Zaretskii <eliz@gnu.org> writes:

    Please report that as a separate bug, and attach one image file of
    each kind that you cannot display.

    > I cannot display any PNG files.  By "cannot display" I
    > mean that what gets displayed is only a 1 cm x 1 cm thin black box
    > (empty) on a
    > white background.

    That's the bug I reported.  Can you do that in the 23.2.90 pretest?

Eli, I started compiling an packing up the binary, when I stopped with
copying libXpm.dll to /bin and thought to myself, `I'm not doing
anything unusual ...'

What do you need me to do?

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> > I see the same problem in both 90 and 91 pretests (and the 
> > latest Windows binary, from 12/20).
> 
> Something's not right with your image DLLs, then.  I think.  I'm quite
> sure that the 90 binary worked for me.

May be.  I just downloaded them yesterday, from GnuWin32.
Try downloading anew and see if you see the same problems.

Of course you might not; there are no doubt differences in our Windows boxes and
our installed software.  But you might, if the problem is in fact "my" DLLs -
they are just the DLLs available now (yesterday) at GnuWin32.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> > Please report that as a separate bug, and attach one image file of
> > each kind that you cannot display.
> 
> Will do.

I've tried twice now.  I get a failure message from Mailer-Daemon@gnu.org for
the address bug-gnu-emacs@gnu.org.  Here is the returned message (below), minus
the encoded images.  Only two of the 3 encoded images seem to be present in the
returned mail, FWIW.

I had no trouble sending the same mail to Sean yesterday, with the same 3 images
plus 3 more.

HTH - Drew

-----------------8<-----------------------

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  bug-gnu-emacs@gnu.org

------ This is a copy of the message, including all the headers. ------
------ The body of the message is 1502934 characters long; only the first
------ 106496 or so are included here.

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From: "Drew Adams" <drew.adams@oracle.com>
To: <bug-gnu-emacs@gnu.org>
Subject: 24.0.50; cannot display any PNG and some JPG, GIF, TIFF
Date: Fri, 24 Dec 2010 10:24:59 -0800
Message-ID: <0F8A8494A89D40FEB2CAB51B859717D4@us.oracle.com>
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This message was returned to me.  I'm trying again, but without the images that
displayed OK, in hopes that the problem was just the total size of the
attachments.

-----Original Message-----
From: Drew Adams Sent: Friday, December 24, 2010 10:14 AM

emacs -Q
 
I downloaded the GnuWin32 setup executables for image support and then
ran them, which put the image DLLs in a folder c:/Program
Files/GnuWin32/bin/.  I put that folder in my PATH.

These are the DLLs that I have in that folder:
 
glut32.dll
jpeg62.dll
libimage.dll
libpng3.dll
libpng12.dll
libpng13.dll
librle3.dll
libtiff3.dll
libungif4.dll
zlib1.dll
 
AFAICT, that should be all I should need.  What am I missing?
 
(In the same folder are lots of *.exe and other files.  There are also several
sibling folders.  I put only the bin folder in PATH (it is the one with the
DLLs.)
 
I have several image files and tested them in Emacs.  I cannot display
any PNG files.  I can display a tiny minority of the JPG and GIF files,
and I can display one of the two TIFF files I have.  When the image is
not displayed, what is displayed is instead a 1 cm x 1 cm hollow black
square on a white background.
 
I've attached two GIF images, two JPG images, and two TIFF images.  The
GIF I can see is beehive*.gif; the GIF I cannot see is drew-emacs-1.gif.
The JPG I can see is drew*palette*.jpg; the JPG I cannot see is
2006*.jpg.  The TIFF I can see is ftp*.tif; the TIFF I cannot see is
http*.tif.

In GNU Emacs 24.0.50.1 (i386-mingw-nt5.1.2600)
 of 2010-12-20 on 3249CTO
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (4.4) --no-opt --cflags
-Ic:/imagesupport/include'
 

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: Sean Sieger <sean.sieger@gmail.com>
> Date: Fri, 24 Dec 2010 13:21:30 -0500
> Cc: 
> 
> What do you need me to do?

Set up your box to support display of PNG images.  Once you have any
Emacs binary that can display PNG, try displaying PNG in the binary
that is in the 23.2.91 pretest zip archive.  My guess would be that it
will not be able to display PNG, even if another binary on the same
machine can.

The ultimate goal is to find out what was it in the 23.2.91 build and
packaging process that needs to be fixed in order to produce a binary
that support all image formats (provided that the necessary DLLs are
present).

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: <sean.sieger@gmail.com>, <7716@debbugs.gnu.org>
> Date: Fri, 24 Dec 2010 10:36:51 -0800
> 
> > > Please report that as a separate bug, and attach one image file of
> > > each kind that you cannot display.
> > 
> > Will do.
> 
> I've tried twice now.  I get a failure message from Mailer-Daemon@gnu.org for
> the address bug-gnu-emacs@gnu.org.  Here is the returned message (below), minus
> the encoded images.  Only two of the 3 encoded images seem to be present in the
> returned mail, FWIW.
> 
> I had no trouble sending the same mail to Sean yesterday, with the same 3 images
> plus 3 more.

Maybe because the attachments make the message too big.  How about if
you try reporting the bug without the attachments first, then respond
to the bug report with several messages, one each with a single image
file that fails to display.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> Maybe because the attachments make the message too big.  How about if
> you try reporting the bug without the attachments first, then respond
> to the bug report with several messages, one each with a single image
> file that fails to display.

Actually, there is _no_ bug (other than the PNG problem that you reported).
That is, with emacs -Q, I am able to see the images that I reported as not
seeing.

I first tried moving the GnuWin32 folder up my PATH hierarchy, after I
discovered that there were several zlib.dll's on my machine.  When I tried with
emacs -Q things were OK.  And the PATH position had no bearing on it.

With my setup I cannot see the images in question, for some reason, but with
emacs -Q I can see them OK.  Guess I'll have to do the binary-search-dot-emacs
dance to find out what the problem is...

Thinking that perhaps the problem was that I use (an old version of) Cygwin, and
that it has its own zlib etc., I tried setting up Cygwin after i started emacs
-Q, but image display still worked OK (modulo the PNG bug), so that's not the
problem.

Anyway, the good news is that there is no need to file a bug, unless I discover
later that the problem comes from Emacs (and not from some of my code).

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: <sean.sieger@gmail.com>, <7716@debbugs.gnu.org>
> Date: Fri, 24 Dec 2010 11:21:12 -0800
> 
> Actually, there is _no_ bug (other than the PNG problem that you reported).
> That is, with emacs -Q, I am able to see the images that I reported as not
> seeing.

That's good to know, thanks.

If you still have the 23.2.90 binary somewhere, could you please try
that as well, and see if PNG can be displayed there?

> Thinking that perhaps the problem was that I use (an old version of) Cygwin, and
> that it has its own zlib etc., I tried setting up Cygwin after i started emacs
> -Q, but image display still worked OK (modulo the PNG bug), so that's not the
> problem.

Make sure Emacs does not try to use the Cygwin versions of the DLLs,
that's known to make trouble, even crashing Emacs.  You could use some
tool to see which DLLs Emacs loads, to be sure (I use Unlocker).

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> If you still have the 23.2.90 binary somewhere, could you please try
> that as well, and see if PNG can be displayed there?

I don't have a 23.2.90, and I don't think I ever saw one.  The builds I've been
getting, including the two latest pretests, all have Emacs 24 as emacs-version.
E.g., 

GNU Emacs 24.0.50.1 (i386-mingw-nt5.1.2600) of 2010-11-09 on 3249CTO.

The Emacs 23.2 _release_ has this emacs-version:
GNU Emacs 23.2.1 (i386-mingw-nt5.1.2600) of 2010-05-08 on G41R2F1.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> Date: Fri, 24 Dec 2010 11:47:02 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: bug-gnu-emacs@gnu.org
> 
> > From: Sean Sieger <sean.sieger@gmail.com>
> > Date: Thu, 23 Dec 2010 15:23:21 -0500
> > Cc: 
> > 
> > (I cannot say it is blissful being as limited as I am.)  Sorry I wasn't
> > reading closely ... um, nope, didn't build any differently.
> 
> That's strange, because the binary of the previous pretest shows PNG
> images.

I take that back.  The precompiled binary from the 23.2.90 pretest on
alpha.gnu.org doesn't display PNG, either.

This is consistent with what Drew sees: none of the precompiled
binaries, including those of Emacs 24 snapshots, can display PNG.

So, Sean, please try to debug this on your machine, because the
binaries I build here don't have that problem.  For starters, where
(from what archive of which package) did you get the PNG headers?

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

> So, Sean, please try to debug this on your machine, because the
> binaries I build here don't have that problem.

Okay.

> For starters, where
> (from what archive of which package) did you get the PNG headers?

From www.zlib.net

zlib version 1.2.5 - April 19th, 2010

and http://www.libpng.org/pub/png/libpng.html

libpng version 1.4.3 - June 26, 2010

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> > Actually, there is _no_ bug (other than the PNG problem 
> > that you reported).  That is, with emacs -Q, I am able to
> > see the images that I reported as not seeing.
> 
> That's good to know, thanks.

The hollow black box I was seeing was because of my frame-fitting code, which
didn't try to handle images (it does now).  The frame was resized to have a
height that was very small, and that caused (dunno why) the image to be shown as
a small hollow box.  IOW, the image was available, but you had to stretch the
frame bigger to be able to see it.

In emacs -Q, even shrinking the frame I don't see that same mini-box effect, so
that might have something to do with something else I use (e.g. standalone
minibuffer frame, whatever).

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> Date: Fri, 24 Dec 2010 17:56:35 -0500
> From: Sean Sieger <sean.sieger@gmail.com>
> Cc: 7716@debbugs.gnu.org
> 
> and http://www.libpng.org/pub/png/libpng.html
> 
> libpng version 1.4.3 - June 26, 2010

Are there Windows binaries available for this version of libpng
somewhere?  The GnuWin32 binaries are for version 1.2.37, not for
1.4.x.  This could be the source of incompatibilities which could
potentially prevent display of PNG images.  I see some hits in Google
for "libpng 1.4 vs 1.2 incompatibilities", and they seem to say that
these two versions are indeed incompatible.

FWIW, I have headers and binaries for version 1.2.8.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

Eli Zaretskii <eliz@gnu.org> writes:

    > and http://www.libpng.org/pub/png/libpng.html
    > 
    > libpng version 1.4.3 - June 26, 2010

    Are there Windows binaries available for this version of libpng
    somewhere?  The GnuWin32 binaries are for version 1.2.37, not for
    1.4.x.  This could be the source of incompatibilities which could
    potentially prevent display of PNG images.  I see some hits in Google
    for "libpng 1.4 vs 1.2 incompatibilities", and they seem to say that
    these two versions are indeed incompatible.

    FWIW, I have headers and binaries for version 1.2.8.

There are security issues with those.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: Sean Sieger <sean.sieger@gmail.com>
> Date: Sat, 25 Dec 2010 05:58:24 -0500
> Cc: 
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
>     > and http://www.libpng.org/pub/png/libpng.html
>     > 
>     > libpng version 1.4.3 - June 26, 2010
> 
>     Are there Windows binaries available for this version of libpng
>     somewhere?  The GnuWin32 binaries are for version 1.2.37, not for
>     1.4.x.  This could be the source of incompatibilities which could
>     potentially prevent display of PNG images.  I see some hits in Google
>     for "libpng 1.4 vs 1.2 incompatibilities", and they seem to say that
>     these two versions are indeed incompatible.
> 
>     FWIW, I have headers and binaries for version 1.2.8.
> 
> There are security issues with those.

There's only one security issue with version 1.2.37, the latest one
available from GnuWin32, and that issue is only relevant to web
browsers.

Anyway, compiling an MS-Windows binary with a library for which
there's no binary DLL available seems useless to me.  If you want to
build with version 1.4.x, please build also the DLL and make it
available.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> Date: Sat, 25 Dec 2010 14:57:43 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: bug-gnu-emacs@gnu.org
> 
> > From: Sean Sieger <sean.sieger@gmail.com>
> > Date: Sat, 25 Dec 2010 05:58:24 -0500
> > Cc: 
> > 
> > Eli Zaretskii <eliz@gnu.org> writes:
> > 
> >     > and http://www.libpng.org/pub/png/libpng.html
> >     > 
> >     > libpng version 1.4.3 - June 26, 2010
> > 
> >     Are there Windows binaries available for this version of libpng
> >     somewhere?  The GnuWin32 binaries are for version 1.2.37, not for
> >     1.4.x.  This could be the source of incompatibilities which could
> >     potentially prevent display of PNG images.  I see some hits in Google
> >     for "libpng 1.4 vs 1.2 incompatibilities", and they seem to say that
> >     these two versions are indeed incompatible.
> > 
> >     FWIW, I have headers and binaries for version 1.2.8.
> > 
> > There are security issues with those.
> 
> There's only one security issue with version 1.2.37, the latest one
> available from GnuWin32, and that issue is only relevant to web
> browsers.
> 
> Anyway, compiling an MS-Windows binary with a library for which
> there's no binary DLL available seems useless to me.  If you want to
> build with version 1.4.x, please build also the DLL and make it
> available.

I downloaded libpng 1.4.5, the latest version, built it, and the
pretest binary indeed can display PNG images using that.  However, the
library name is libpng14.dll, which is not in image-library-alist;
adding it there would be a bad idea due to incompatibilities between
1.2.x and 1.4.x versions.

I will next try to find a way to tweak our PNG-related code to be able
to use either version of the shared libraries, in the hope that this
is possible.  If not, we will have some hard decisions to make.

P.S. Building libpng on Windows is very easy (there's a MinGW specific
Makefile in the distro).

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Sean Sieger]

On Wed, Dec 29, 2010 at 1:05 PM, Eli Zaretskii <eliz@gnu.org> wrote:

> I downloaded libpng 1.4.5, the latest version, built it, and the
> pretest binary indeed can display PNG images using that.  However, the
> library name is libpng14.dll, which is not in image-library-alist;
> adding it there would be a bad idea due to incompatibilities between
> 1.2.x and 1.4.x versions.
>
> I will next try to find a way to tweak our PNG-related code to be able
> to use either version of the shared libraries, in the hope that this
> is possible.  If not, we will have some hard decisions to make.
>
> P.S. Building libpng on Windows is very easy (there's a MinGW specific
> Makefile in the distro).

Right?  Yeah, remember I when I had first started building those
weekly binaries, someone noticed that they were considerably
bigger compressed files ... or some such.  Anyway, I had built
all of the new image dll's and built the weekly Emacs and I
think, a pretest or a release ... probably release, right?  And it
didn't go over well because of licensing.  I took 'em all out and
used only the freshest headers.  That's when that started ...
with making the new libxpm and so on. Sorry for making the
buuug.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Jason Rumney]

On 25/12/2010 20:57, Eli Zaretskii wrote:
> There's only one security issue with version 1.2.37, the latest one
> available from GnuWin32, and that issue is only relevant to web
> browsers.
>    

It might be worth checking what version is distributed with GTK for 
Windows. It is likely to be more up to date than GnuWin32.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> Date: Thu, 30 Dec 2010 07:57:28 +0800
> From: Jason Rumney <jasonr@gnu.org>
> Cc: 
> 
> On 25/12/2010 20:57, Eli Zaretskii wrote:
> > There's only one security issue with version 1.2.37, the latest one
> > available from GnuWin32, and that issue is only relevant to web
> > browsers.
> >    
> 
> It might be worth checking what version is distributed with GTK for 
> Windows. It is likely to be more up to date than GnuWin32.

According to http://www.gtk.org/download-windows.html, they currently
provide 1.4.3.  But I fail to see how this resolves the problem at
hand, given the binary incompatibilities between 1.2.x and 1.4.x.  Are
you suggesting that we tell all Windows users to get libpng only from
the GTK site?  What about all those who already have 1.2.x installed
and will not even look into README.W32 when they install a newer
binary?

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Jason Rumney]

Eli Zaretskii <eliz@gnu.org> writes:

> According to http://www.gtk.org/download-windows.html, they currently
> provide 1.4.3.  But I fail to see how this resolves the problem at
> hand, given the binary incompatibilities between 1.2.x and 1.4.x.

It seems to solve it perfectly well. The current binaries are compiled
against 1.4.x, so if GTK is providing a 1.4.x binary, we can tell users
to get it there. What's more, GTK has a single easy to use installer
that inserts registry entries that addpm.exe already detects and
configures Emacs to use GTK libraries if it finds them, vs GnuWin32's
separate installers for each library.

> Are you suggesting that we tell all Windows users to get libpng only
> from the GTK site?  What about all those who already have 1.2.x
> installed and will not even look into README.W32 when they install a
> newer binary?

Faced with a choice between 1.4 and an old 1.2 with known security
vulnerabilities, I know which one I'd rather recommend to users.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: Jason Rumney <jasonr@gnu.org>
> Cc: bug-gnu-emacs@gnu.org
> Date: Thu, 30 Dec 2010 23:58:46 +0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> Faced with a choice between 1.4 and an old 1.2 with known security
> vulnerabilities, I know which one I'd rather recommend to users.

I agree, but I don't want to force users who build their own Emacs to
upgrade to a newer libpng just to have PNG support in Emacs.  So I
installed (on the emacs-23 branch) a set of changes that expose to
Lisp the version of libpng against which Emacs was compiled, and then
w32-win.el sets up the PNG part of image-library-alist
(dynamic-library-alist in Emacs 24) as appropriate for what was used
during compilation.

While at that, I also fixed image.c to avoid a compiler warning due to
direct access to png_ptr->jmpbuf.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

Just to follow up on the PNG display problem -

PNG is still not displayed in the latest Windows build I have:
GNU Emacs 24.0.50.1 (i386-mingw-nt5.1.2600) of 2011-01-03 on 3249CTO

However, if I use `image-dired' in a directory that has PNG files, then PNG
thumbnails show fine and clicking mouse-2 on a PNG's thumbnail shows the PNG
fine.

That uses a different method for showing the image, however (it launches a shell
command etc.).  Just mentioning that PNG can be displayed, but just not by
`find-file' and company.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: <sean.sieger@gmail.com>, <7716@debbugs.gnu.org>
> Date: Mon, 10 Jan 2011 14:59:06 -0800
> 
> Just to follow up on the PNG display problem -
> 
> PNG is still not displayed in the latest Windows build I have:
> GNU Emacs 24.0.50.1 (i386-mingw-nt5.1.2600) of 2011-01-03 on 3249CTO

What's the value of the variable libpng-version, and what version of
libpng do you have installed?  These two need to match; see README.W32
in the distro, under "Image libraries".

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> > PNG is still not displayed in the latest Windows build I have:
> > GNU Emacs 24.0.50.1 (i386-mingw-nt5.1.2600) of 2011-01-03 on 3249CTO
> 
> What's the value of the variable libpng-version,

libpng-version's value is 10403
Documentation:
Not documented as a variable.

> and what version of libpng do you have installed?

How would I know? Looking at Properties > Version for each of these files:

libpng3.dll,  File version: 1.2.37.3442
libpng12.dll, File version: 1.2.37.3442
libpng13.dll, File version: 1.2.8.1799

No idea what any of those mean, of if they have anything to do with the "version
of libpng" I have installed.  I picked up the libpng (and other) dlls from where
you and Sean said to pick them up (GNUWin32) after the date when you told me
where to get them.

PNG didn't work then, and it still doesn't work now.

> These two need to match; see README.W32
> in the distro, under "Image libraries".

There is no "Image libraries" in README.W32.
There is a heading "Image support", with this text about PNG:

      PNG: requires the PNG reference library 1.4 or later, which will
      be named libpng14.dll or libpng14-14.dll.  LibPNG requires zlib,
      which should come from the same source as you got libpng.
      Starting with Emacs 23.3, the precompiled Emacs binaries are
      built with libpng 1.4.x and later, and are incompatible with
      earlier versions of libpng DLLs.  So if you have libpng 1.2.x,
      the PNG support will not work, and you will have to download
      newer versions.

Where does that leave us?  The only LibPng setup file I see at GNUWin32 is
1.2.37: http://gnuwin32.sourceforge.net/packages/libpng.htm
(libpng-1.2.37-setup.exe).

I also installed (the latest) ImageMagick more recently, because Tassilo Horn
suggested it would enable me to see Windows *.ico images. But it does not. He
has since guessed that Emacs itself needs to have been built with ImageMagick
present in order for it to help with .ico files.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: <sean.sieger@gmail.com>, <7716@debbugs.gnu.org>
> Date: Mon, 10 Jan 2011 20:41:26 -0800
> 
> > > PNG is still not displayed in the latest Windows build I have:
> > > GNU Emacs 24.0.50.1 (i386-mingw-nt5.1.2600) of 2011-01-03 on 3249CTO
> > 
> > What's the value of the variable libpng-version,
> 
> libpng-version's value is 10403
> Documentation:
> Not documented as a variable.
> 
> > and what version of libpng do you have installed?
> 
> How would I know? Looking at Properties > Version for each of these files:
> 
> libpng3.dll,  File version: 1.2.37.3442
> libpng12.dll, File version: 1.2.37.3442
> libpng13.dll, File version: 1.2.8.1799

This is version 1.2.x of libpng, while libpng-version's value, 10403,
means that Emacs looks for version 1.4.3 or later.  If you evaluate
`(image-type-available-p 'png)', you should see nil.

You need to download a newer version of libpng.

> > These two need to match; see README.W32
> > in the distro, under "Image libraries".
> 
> There is no "Image libraries" in README.W32.

Sorry, it was 6AM outside and cold, so my brain didn't warm up yet.

> Where does that leave us?  The only LibPng setup file I see at GNUWin32 is
> 1.2.37: http://gnuwin32.sourceforge.net/packages/libpng.htm
> (libpng-1.2.37-setup.exe).

You will find libpng 1.4.x here:

  http://www.gtk.org/download-windows.html

With this newer version, PNG support should work.  You may need to
restart Emacs, though (but I'm not sure, so try without first).

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> You need to download a newer version of libpng.
> You will find libpng 1.4.x here:
>   http://www.gtk.org/download-windows.html
> With this newer version, PNG support should work.  You may need to
> restart Emacs, though (but I'm not sure, so try without first).

Works fine; thanks!

Comments:

1. This stuff is not obvious.
2. Consider updating GNUWin32 or asking them to update the site.
3. The README.W32 mentions the site you just cited.  But it also
   mentions GnuWin32.  The README.W32 should make clear just what
   you need (which versions) and where to get it (all!).  Mention
   any considerations about versions such as what you described.
4. Emacs should also support *.ico files (MS Windows icon images).
   AFAIK, none of the downloads listed provide this support.
   Tassilo Horn suggested installing ImageMagick to get icon
   support, but I did that and it didn't work.  He has since said
   that he suspects that Emacs needs to built with ImageMagick
   present for this to work (icon support).

This should not be so complicated.  Windows users - above all other users (since
more Windows users are not programmers) - should be given a failsafe,
braindead-simple way to get images to work in Emacs.

Just one opinion.  Thx.

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Cc: <sean.sieger@gmail.com>, <7716@debbugs.gnu.org>
> Date: Tue, 11 Jan 2011 11:19:38 -0800
> 
> This should not be so complicated.  Windows users - above all other users (since
> more Windows users are not programmers) - should be given a failsafe,
> braindead-simple way to get images to work in Emacs.

The only way to make this dead simple is to statically link Emacs
against all image libraries.  This will make a much larger binaries,
so I'm not sure we want that.

The other alternative is to distribute the DLLs together with Emacs.
Unfortunately, this has legal complications.

It is unfortunate that libpng developers made an incompatible change
between version 1.2 and 1.4.  This is what started this whole issue.
There are no such problems with other image libraries.

I will see what I can do about the other points you raise (except for
.ico support: I have no idea what's involved).

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Drew Adams]

> I will see what I can do about the other points you raise (except for
> .ico support: I have no idea what's involved).

Thanks.

I do hope someone will really look into the icon issue.  IMO file-type icons are
a big help in Windows (and users are used to them).  I would like to add them
(optionally) here and there (e.g. Dired) for users.  (Emacs could do likewise,
to the degree that that is not verboten.)

bug#7716: 23.2.91; Pretest Windows binary doesn't support PNG images

[Lennart Borgman]

On Tue, Jan 11, 2011 at 8:31 PM, Eli Zaretskii <eliz@gnu.org> wrote:
>> From: "Drew Adams" <drew.adams@oracle.com>
>> Cc: <sean.sieger@gmail.com>, <7716@debbugs.gnu.org>
>> Date: Tue, 11 Jan 2011 11:19:38 -0800
>>
>> This should not be so complicated.  Windows users - above all other users (since
>> more Windows users are not programmers) - should be given a failsafe,
>> braindead-simple way to get images to work in Emacs.
>
> The only way to make this dead simple is to statically link Emacs
> against all image libraries.  This will make a much larger binaries,
> so I'm not sure we want that.
>
> The other alternative is to distribute the DLLs together with Emacs.
> Unfortunately, this has legal complications.

Aren't there more alternatives? How about just storing the relevant
image dll:s somewhere where Emacs users can grab them? I do not think
there are any legal complications doing that as long as you tell where
the sources are etc.