[PD-dev] pix_multiblob mem leak

[Gerrie Roos]

This is the first time looking at pd/gem code, so I might have it
completely wrong, but the following looks suspicious:

pix_multiblob.cpp:216:
  t_atom*ap = new t_atom[2+blobNumber*8];

ap then gets passed to outlet_anything and never freed.  I looked at
some other examples of outlet_* usage and it always looks as if the
memory passed is on the stack or freed again by the caller, e.g.:
pix_record.cpp:184 is on the stack.  Is data always copied between
outlet/inlets or am I missing some mechanism that optimizes by
transferring pointer ownership?

I couldn't find anything else in there that looks like it might leak.


2010/3/14 Gerrie Roos <gerrieroos at gmail.com>:
> Hi, tnx for the reply!
>
> I started with Pd extented 0.41.4 (that's using Gem 0.91 I think) then
> I installed a file marked as gem-0.92.2-W32-i686.exe (fresh from
> http://gem.iem.at/) but if I look at the release notes in there it
> looks like 0.91 as well, but the .dll is a different size, so I assume
> the release notes are not up-to-date and I'm running 0.92.2.  Pd also
> prints out 0.92.2 when it starts up.  Sorry, no beer yet...
>
> Clock.avi comes standard with Windows XP at least.  Here's a copy:
> http://www.sendspace.com/file/smz01u
>
> Can't load alea.mpg with pix_film...just get an 'unable to open
> file...error.  Weird.
>
> Tried homer.avi, also leaks 8(
>
> Originally found the problem using my usb webcam and played around
> with the number of blobs quite a lot.  It always leaks when blobs are
> detected.  Probably not the webcam since it leaks with clock.avi and
> homer.avi as well.
>
>
> 2010/3/14 IOhannes zmölnig <zmoelnig at iem.at>:
>> Gerrie Roos wrote:
>>> Hi!
>>>
>>> It looks like pix_multiblob is leaking about 4kB/frame/blob.  Anybody
>>> else seen this?  I'm in a bit of a tight spot.  I've got an
>>> installation coming up on 18 March and my extensive pd patch is now
>>> running out of memory every couple of hours.  Would love to check out
>>> the source code and try fix it myself but since I've never done any pd
>>> dev it will put me back a couple of days (at the least).  I'll buy you
>>> beer!
>>>
>>> Windows XP SP2
>>> Pd version 0.41.4-extended
>>
>> what Gem version is this?
>> does the problem exist with the latest and greatest Gem (0.92.2)? (if
>> not, i claim the beer :-))
>>
>>
>> thanks for sending an example patch; it's pretty generic, and i do not
>> see any memleak occuring here (using the alea.mpg example film).
>> however, the bug might be related to the number of blobs found and the
>> image format, neither of which i can reproduce;
>> could you put the clock.avi online somewhere so i can download it?
>> or: how does your patch behave with homer.avi?
>>
>> fmadrs
>> IOhannes
>>
>>
>