From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00
	autolearn=unavailable autolearn_force=no version=3.4.4
X-Received: by 2002:a24:39c1:: with SMTP id
 l184-v6mr2051618ita.18.1530102875359;
        Wed, 27 Jun 2018 05:34:35 -0700 (PDT)
X-Received: by 2002:a9d:70c2:: with SMTP id w2-v6mr339315otj.2.1530102875086;
 Wed, 27 Jun 2018 05:34:35 -0700 (PDT)
Path: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!feeder.eternal-september.org!news.uzoreto.com!weretis.net!feeder6.news.weretis.net!feeder.usenetexpress.com!feeder-in1.iad1.usenetexpress.com!border1.nntp.dca1.giganews.com!nntp.giganews.com!d7-v6no1773162itj.0!news-out.google.com!p13-v6ni2144itf.0!nntp.google.com!u78-v6no1757140itb.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail
Newsgroups: comp.lang.ada
Date: Wed, 27 Jun 2018 05:34:34 -0700 (PDT)
In-Reply-To: <43e020d3-653d-4a38-9795-a84966b50bf0@googlegroups.com>
Complaints-To: groups-abuse@google.com
Injection-Info: glegroupsg2000goo.googlegroups.com;
 posting-host=2602:304:cda2:5210:89a:a7de:e1be:2fe2;
 posting-account=W2gdXQoAAADxIuhBWhPFjUps3wUp4RhQ
NNTP-Posting-Host: 2602:304:cda2:5210:89a:a7de:e1be:2fe2
References: <f4c544c8-bbdf-48da-a27a-7611b880537d@googlegroups.com>
 <2b125d10-065d-404a-a8d3-1c5debe4b3a2@googlegroups.com>
 <43e020d3-653d-4a38-9795-a84966b50bf0@googlegroups.com>
User-Agent: G2/1.0
MIME-Version: 1.0
Message-ID: <b944eb10-24e8-4826-9fe0-2fef0e2b1e34@googlegroups.com>
Subject: Re: Problem Building Ada Interface To ImageMagick 7
From: Stephen Leake <stephen_leake@stephe-leake.org>
Injection-Date: Wed, 27 Jun 2018 12:34:35 +0000
Content-Type: text/plain; charset="UTF-8"
Xref: reader02.eternal-september.org comp.lang.ada:53373
Date: 2018-06-27T05:34:34-07:00
List-Id: <comp.lang.ada>

On Tuesday, June 26, 2018 at 8:13:03 AM UTC-5, Roger wrote:
> On Tuesday, June 26, 2018 at 7:34:57 PM UTC+10, gautier...@hotmail.com wrote:
> > Is there something specific you want to do with ImageMagick ?
> 
> The current specific thing I'm trying to do (in support of a larger project) is to get ImageMagick to read an image file and writing the image to another file.

One way to do this is to use gnat.os_lib spawn, and run the imagemagick executable. For example, I have this:

   procedure To_Jpeg (I : in Cursor)
   is
      use GNAT.OS_Lib;
      Filename     : constant String  := Element (I);
      Ext_First    : constant Integer := Filename'Last - 3;
      Jpg_Filename : constant String  := Filename (Filename'First .. Ext_First - 1) & ".jpg";
      Success      : Boolean;
   begin
      --  Calling 64 bit cygwin 'convert' from 32 bit native GNAT
      --  screws up, so we use a 32 bit native install of ImageMagick.
      Spawn ("d:/Apps/ImageMagick-7.0.3-Q8/magick.exe",
             (new String'("convert"),
              new String'(Filename),
              new String'("-quality"),
              new String'("50"), -- good for fine text, reasonably small
              new String'(Jpg_Filename)), Success);

      if not Success then
         raise Ada.Text_IO.Use_Error with "convert failed";
      end if;

      File_Names.Replace_Element (I, Jpg_Filename);
   end To_Jpeg;