uploading a data:image/imagetype,base64 in perl

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

Hi, I am using a Cropit.js to let my users customize their uploaded images but the problem is, it uses: data:image/png;base64,iVBORw0k... so what i did is i've used the MIME::Base64 Perl Module. So here's how i did it:

<!--
MY HTML FORM
-->
<form action="upload.pl" method="post" enctype="multipart/form-data">
<div class="image-editor">
<input type="file" class="cropit-image-input" />
<div class="cropit-preview"></div>
<div class="image-size-label">
Resize Image:
</div>
<input type="range" class="cropit-image-zoom-input" />
<input type="hidden" name="imagedata" class="hidden-image-data" />
<button type="submit">save</button>
</div>
</form>
<!--
END OF HTML FORM
-->
[download]

Here's my Perl Code:

#!/usr/bin/perl

use strict;
use warnings;
use CGI;
use MIME::Base64;

my $arg=new CGI;

my $fetch_photo=$arg->param('imagedata');
my $decoded=MIME::Base64::decode_base64($fetch_photo);
my $filename;
$filename=int rand(1000).".png" if $fetch_photo=~/png/;
$filename=int rand(1000).".jpg" if $fetch_photo=~/jpg/;
open(FILE, ">img/$filename") or die 'err';
binmode FILE;
print FILE $decoded;
close(FILE);
[download]

It keeps uploading a unreadable/corrupted image file please help! thank you.

Comment on uploading a data:image/imagetype,base64 in perl Select or Download Code

Replies are listed 'Best First'.
Re: uploading a data:image/imagetype,base64 in perl by Mr. Muskrat (Canon) on Dec 04, 2017 at 20:14 UTC
It looks like you need to remove 'data:image/png;base64,' from the beginning of $fetch_photo before you pass it into decode_base64. Update: Here's an updated script that improves upon how you were doing things. It passed cursory testing. `#!/usr/bin/perl use strict; use warnings; use CGI; use MIME::Base64; my $arg = new CGI; my $fetch_photo = $arg->param('imagedata'); my ($data, $base64) = split /,/, $fetch_photo; my ($type) = $data =~ m!data:image/(\w+);base64!; my $decoded = MIME::Base64::decode_base64($base64); my $filename = int(rand(1000)) . '.' . $type; open(my $file, '>', "img/$filename") or die 'err'; # 3 argument open binmode $file; print $file $decoded; close($file);` [download]	[reply] [d/l]
Re: uploading a data:image/imagetype,base64 in perl by Corion (Patriarch) on Dec 04, 2017 at 18:36 UTC
Maybe there is some other data in front of the data you fetch from `->param('imagedata')`? Maybe save the raw base64 data to a file first and have a look at it? MIME::Base64 doesn't document any kind of error handling, so I would look at the raw data coming in first.	[reply] [d/l]