how do i convert from tiff to png images

d_i_r_t_y has asked for the wisdom of the Perl Monks concerning the following question:

...on the fly using Image::Magick, after pulling out the raw binary data from a DB? i have tried the recommended code:

 my $raw_tiff = get_from_DB();
 my $image = new Image::Magick ( magick => 'PNG' );
 $image->BlobToImage( $raw_tiff );
 my $raw_png = $image->ImageToBlob();
[download]

This, however, does not work -- the raw tiff is not converted at all, merely returned as-is.

Has anyone got this working?

d_i_r_t_y

Comment on how do i convert from tiff to png images Download Code

Replies are listed 'Best First'.
Re: how do i convert from tiff to png images by arturo (Vicar) on Jun 13, 2001 at 17:43 UTC
I believe you've misunderstood what those methods are supposed to do. That bit of code isn't supposed to allow conversion between different graphical formats, it's supposed to get you from a blob to image data (i.e. you get out the binary data that went in as a blob; it doesn't say it will convert to a different format in the process). I would assume you want to use `convert` once you've got the TIFF, but it's not clear from the docs what the Perl hook into that is. You could write the file to disk and, since you have the imagemagick stuff installed, spawn a subshell that calls `convert`: `$image->write('temp.tiff'); system ("/path/to/convert temp.tiff png:newname.png") && die "Couldn't convert image";` [download] ( I think you're right to be a little frustrated with those docs, they're not forthcoming on how to use convert in Perl ) `perl -e 'print "How sweet does a rose smell? "; chomp ($n = <STDIN>); +$rose = "smells sweet to degree $n"; other_name = rose; print "$oth +er_name\n"'` [download]	[reply] [d/l] [select]
Re: how do i convert from tiff to png images by shotgunefx (Parson) on Jun 13, 2001 at 19:01 UTC
PerlMagick doesn't have a convert method. If you write the file it will automatically convert it based on the saving extension. You would think the docs would have an example or mention such a common task. So if this is something you are not going to be doing on every request, I would just save it to a temp file with a ".png" extension, read it back in and store it wherever you wanted it in the first place. -Lee "To be civilized is to deny one's nature."	[reply]