Bug #15994 for Image-Size: Incorrect use of Compress::Zlib in CWS (flash 6) size

Mon Nov 21 04:51:19 2005 Guest - Ticket created

Subject:

Incorrect use of Compress::Zlib in CWS (flash 6) size

Just small patch for Image::Size module, flash MX (compressed flash) part. Problem is Compress::Zlib::uncompress wants to read complete compressed block and will return empty result otherwise. For swf file larger than internal function's buffer size it will fail to uncompress buffer and thus unable to determine size. Patch in attachment replaces uncompress with inflate, which is streaming realisation and will inflate part of the buffer it able to. Tested with: Compress::Zlib 1.39 Image::Size 2.992 perl v5.8.0 built for i386-linux-thread-multi

Download patch
application/octet-stream 233b

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Mon Nov 21 04:53:23 2005 Guest - Correspondence added

From:

mrj [...] mrj.spb.ru

Attachment -- swf image for testing, should report size 280x140, CWS format

Download 8.swf
application/x-shockwave-flash 14k

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Mon Mar 13 02:55:02 2006 Guest - Correspondence added

From:

James Austin

On Mon Nov 21 04:51:19 2005, guest wrote: Show quoted text

> Just small patch for Image::Size module, flash MX (compressed flash) > part. > > Problem is Compress::Zlib::uncompress wants to read complete > compressed block and will return empty result otherwise. For swf > file larger than internal function's buffer size it will fail to > uncompress buffer and thus unable to determine size. Patch in > attachment replaces uncompress with inflate, which is streaming > realisation and will inflate part of the buffer it able to. > > Tested with: > Compress::Zlib 1.39 > Image::Size 2.992 > perl v5.8.0 built for i386-linux-thread-multi

Your patch still seems to fail with some movies, for some reason $header = $d->inflate(substr($header, 8, 1024)); (Using perl v5.8.0 MSWin32-x86-multi-thread, Image::Size 2.992, Compress::Zlib 1.39). Produces an out of range error with some movies, breaking the line into two seems to fix this for some reason. e.g. $header = substr($header, 8, 1024); $header = $d->inflate($header); Such that to fix the bug: Replace: $header = substr($header, 8, 1024); $header = Compress::Zlib::uncompress($header); With: my ($d, $status) = Compress::Zlib::inflateInit(); $header = substr($header, 8, 1024); $header = $d->inflate($header);

Mon Mar 13 02:55:03 2006 The RT System itself - Status changed from 'new' to 'open'

Sat Jun 10 00:57:38 2006 rjray [...] blackperl.com - Correspondence added

Patch applied, the test file integrated into the distribution, and a new test added to t/all.t. This will be delivered in the 3.0 release.

Sat Jun 10 00:57:39 2006 rjray [...] blackperl.com - Status changed from 'open' to 'resolved'