in reply to reading image blob w/Image::Magick

The PerlMagick docs have a 'Working with Blobs' section -- there are ImageToBlob() and BlobToImage() methods ..

Also, you could use IO::Scalar to create a filehandle for the string and pass that to Image::Magick

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Re^2: reading image blob w/Image::Magick
by salva (Canon) on Apr 16, 2006 at 21:43 UTC
    the objects provided by modules like IO::Scalar are not backed by real file descriptors at the OS level, and so, they can not be passed to C functions requiring open files as arguments (unless those functions have been modified to use PerlIO, but this is quite rare).
[reply]
      Image::Magick can read from perl filehandles though: 
        $image = Image::Magick->new;
  open(IMAGE, 'image.gif');
  $image->Read(file=>\*IMAGE);
  close(IMAGE);

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      despite that, IO::Scalar wouldn't work?
[reply]
[d/l]
        open(IMAGE, 'image.gif') opens a real file using the OS services but IO::Scalar objects exists only inside perl.

        You can see the difference using the fileno() builtin: 

        open IMAGE, "image.gif";
printf "fn: %d\n", fileno(IMAGE);

my $ios = IO::Scalar->new;
printf "fn: %d\n", fileno($ios);

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