Doc-view failing to generate image

Doc-view failing to generate image

[Edward Lilley]

Hi all

I'm getting a funny error when trying to open (simple C-x C-f) PDF files
in doc-view mode. The png appears in /tmp/docview500/foo, but then the
image doesn't actually appear in the buffer -- and then *Messages* shows
the error:

ImageMagick error: NoDecodeDelegateForThisImageFormat
\ `/tmp/docview500/obsmltest.pdf-07534b262c8761286817c76762acef2c/page-1.png'
\ @ error/constitute.c/ReadImage/550 [2 times]

(line breaks added)

...which is a bit baffling.

Any ideas? Poking around in doc-view.el left me none the wiser (it seems
the above is an ImageMagick error, but I can't see exactly where
doc-view calls an ImageMagick program)

Using: GNU Emacs 24.2.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.4.4)

thanks,
Edward

Re: Doc-view failing to generate image

[Jambunathan K]

Edward Lilley <ejlilley@gmail.com> writes:

> Hi all
>
> I'm getting a funny error when trying to open (simple C-x C-f) PDF files
> in doc-view mode. The png appears in /tmp/docview500/foo, but then the
> image doesn't actually appear in the buffer -- and then *Messages* shows
> the error:
>
> ImageMagick error: NoDecodeDelegateForThisImageFormat
> \ `/tmp/docview500/obsmltest.pdf-07534b262c8761286817c76762acef2c/page-1.png'
> \ @ error/constitute.c/ReadImage/550 [2 times]
>
> (line breaks added)
>
> ...which is a bit baffling.

M-x report-emacs-bug RET

Let experts figure out what the deal is.

> Any ideas? Poking around in doc-view.el left me none the wiser (it seems
> the above is an ImageMagick error, but I can't see exactly where
> doc-view calls an ImageMagick program)

Meanwhile, try disabling imagemagick or play around with the following
variables, visible via M-x customize-group RET image

,----
| Show Value Imagemagick Enabled Types 
|    List of ImageMagick types to treat as images. More
| 
| Show Value Imagemagick Types Inhibit 
|    List of ImageMagick types that should never be treated as images. More
`----

You can also search for imagemagick in NEWS file - C-h n.

Here are the top few entries.

,----
| ** ImageMagick support, if available, is automatically enabled.
| It is no longer necessary to call `imagemagick-register-types'
| explicitly to install ImageMagick image types; that function is called
| automatically at startup, or when customizing a relevant imagemagick-
| option.
| +++
| *** Setting `imagemagick-types-inhibit' to t now disables the use of
| ImageMagick to view images.  You must call imagemagick-register-types
| afterwards if you do not use customize to change this.
| +++
| *** The new variable `imagemagick-enabled-types' also affects which
| ImageMagick types are treated as images.  The function
| `imagemagick-filter-types' returns the list of types that will be
| treated as images.
| ---
| *** Images displayed via ImageMagick now support transparency and the
| :background image spec property.
| 
| 
| ** Emacs can be compiled with ImageMagick support.
| This happens by default if a suitably recent version of the library is
| found at build time.  To prevent this, use the configure option
| `--without-imagemagick'.  See below for ImageMagick features.
| This feature is not available for the Nextstep or MS ports.
`----



> Using: GNU Emacs 24.2.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.4.4)
>
> thanks,
> Edward
>
>
>
>

-- 

Re: Doc-view failing to generate image

[Tassilo Horn]

Edward Lilley <ejlilley@gmail.com> writes:

Hi Edward,

> I'm getting a funny error when trying to open (simple C-x C-f) PDF
> files in doc-view mode. The png appears in /tmp/docview500/foo, but
> then the image doesn't actually appear in the buffer -- and then
> *Messages* shows the error:
>
> ImageMagick error: NoDecodeDelegateForThisImageFormat
> \ `/tmp/docview500/obsmltest.pdf-07534b262c8761286817c76762acef2c/page-1.png'
> \ @ error/constitute.c/ReadImage/550 [2 times]
>
> (line breaks added)
>
> ...which is a bit baffling.

It seems your ImageMagick hasn't been compiled with PNG support.  Does

  $ identify -list format

include PNG with mode "rw-"?  Also,

  $ identify -list configure

should include --with-png in CONFIGURE and png in DELEGATES.

What distro are you using?

Bye,
Tassilo

Re: Doc-view failing to generate image

[Edward Lilley]

Tassilo Horn <tsdh@gnu.org> writes:

> Edward Lilley <ejlilley@gmail.com> writes:
>
> Hi Edward,
>
>> I'm getting a funny error when trying to open (simple C-x C-f) PDF
>> files in doc-view mode. The png appears in /tmp/docview500/foo, but
>> then the image doesn't actually appear in the buffer -- and then
>> *Messages* shows the error:
>>
>> ImageMagick error: NoDecodeDelegateForThisImageFormat
>> \
>> /tmp/docview500/obsmltest.pdf-07534b262c8761286817c76762acef2c/page-1.png'
>> \ @ error/constitute.c/ReadImage/550 [2 times]
>>
>> (line breaks added)
>>
>> ...which is a bit baffling.
>
> It seems your ImageMagick hasn't been compiled with PNG support.  Does
>
>   $ identify -list format
>
> include PNG with mode "rw-"?  Also,
>
>   $ identify -list configure
>
> should include --with-png in CONFIGURE and png in DELEGATES.

Hi, thanks for the response.

It actually seems I've fixed it with a package update & relaunching
emacs -- I think an update of ImageMagick (or similar) while emacs was
running confused it somehow.

> What distro are you using?

(for the record: I'm using Arch -- perhaps more prone to these strange
mix-ups!)

> Bye,
> Tassilo
>

thanks,
Edward