php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login
Bug #59407 getimageblob() on Imagick object from tiff file produces random md5 hashes
Submitted: 2010-09-08 19:28 UTC Modified: 2010-11-18 06:49 UTC
Votes:1
Avg. Score:5.0 ± 0.0
Reproduced:1 of 1 (100.0%)
Same Version:0 (0.0%)
Same OS:0 (0.0%)
From: matvey at copters dot ru Assigned:
Status: Wont fix Package: imagick (PECL)
PHP Version: 5.2.8 OS: Linux Debian Lenny 64
Private report: No CVE-ID: None
Have you experienced this issue?
Rate the importance of this bug to you:

 [2010-09-08 19:28 UTC] matvey at copters dot ru
Description:
------------
getimageblob() on Imagick object from tiff file produces 
random md5 hashes:

rgp@cp ~/src $ cat s.php
<?php
$s = array(
  1,
  2,
  3,
  4,
  5,
  6,
  7,
  8,
  9,
  10,
);

foreach ($s as $t) {
  $ob = new Imagick("test.tif");
  $hash = hash('md5', $ob->getimageblob());
  echo "{$hash} \n";
}
?>
rgp@cp ~/src $ php -f s.php 
3a0eff2dc635064f91f9720e4f02fc25 
0e15adc163724345c26305df4cb2faed 
0e15adc163724345c26305df4cb2faed 
a6577644313c4fbd5014028c16a78e84 
dd391a6977cc7a6af56037959d607c90 
dd391a6977cc7a6af56037959d607c90 
83caff49e5d8abe704cf8c298770314f 
e85136bd4259b4b18e8f0bbc9867da9b 
36bdf4fc1806f83040b71a7214cc1d4c 
491f7bc84db9b83602f9d5ebc13f530a

and:

rgp@cp ~/src $ cat s.php
<?php
$s = array(
  1,
  2,
  3,
  4,
  5,
  6,
  7,
  8,
  9,
  10,
);

foreach ($s as $t) {
  $ob = new Imagick("test.tif");
  $hash = hash('md5', $ob->getimageblob());
  echo "{$hash} \n";
}
?>
rgp@cp ~/src $ php -f s.php 
3a0eff2dc635064f91f9720e4f02fc25 
0e15adc163724345c26305df4cb2faed 
0e15adc163724345c26305df4cb2faed 
a6577644313c4fbd5014028c16a78e84 
dd391a6977cc7a6af56037959d607c90 
dd391a6977cc7a6af56037959d607c90 
83caff49e5d8abe704cf8c298770314f 
e85136bd4259b4b18e8f0bbc9867da9b 
36bdf4fc1806f83040b71a7214cc1d4c 
491f7bc84db9b83602f9d5ebc13f530a

does not.




Patches

Add a Patch

Pull Requests

Add a Pull Request

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2010-09-08 19:30 UTC] matvey at copters dot ru
sorry to repost: 
on the same file:

rgp@cp ~/src $ cat f.php 
<?php
$s = array(
  1,
  2,
  3,
  4,
  5,
  6,
  7,
  8,
  9,
  10,
);

foreach ($s as $t) {
  $hash = hash_file('md5', "test.tif");
  echo "{$hash} \n";
}
?>
rgp@cp ~/src $ php -f f.php 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12 
be42c81505f2c9ef70994c60915a3f12
 [2010-11-18 06:49 UTC] mkoppanen@php.net
Hello,

I took your code and wrote two tif files to disk. It seems that the differences in the hashes come from timing / rounding issues:

1c1
< Image: b.tif
---
> Image: a.tif
79,81c79,81
<   Pixels per second: 10.24MB
<   User time: 0.120u
<   Elapsed time: 0:01.120
---
>   Pixels per second: 9.452MB
>   User time: 0.130u
>   Elapsed time: 0:01.129
 
PHP Copyright © 2001-2019 The PHP Group
All rights reserved.
Last updated: Mon Jun 24 18:01:26 2019 UTC