SWC errors, while SWF works fine, why?

Question

Edit: I have tried using pure theora libs (no ffmpeg) and the same result - I have created a simple app showing theora info. When launched as standalone,works (shows theora version). As  SWC, error "can't allocate encoder context". Anyone any idea why it's failing with allocations in SWC? This is really frustrating, seems I can't get anything video related to work. Is SWC able to support anything more than some simple C stuff?
Hi, I'm trying to make ffmpeg work through my custom SWC library which would encode multiple frames to MPEG1. I was "almost" finished now -  managed to put together a test app which upon exporting to SWF displays nice progress log(I'm test encoding 25 frames in MPEG1, so it shows encoding frame 1... X bytes, encoding frame 2...X bytes etc.), all is great up to this point.
The problem is, when I emit this to swc. When calling my magic encode test function in the SWC - first, I've got stack overflow error in "dsputil_static_init". This was already weird, but I figured out that I didn't need the static init for mpeg1 encoding after exploring ffmpeg a bit, so I tried to disable this call in ffmpeg source. Then recompiled ffmpeg, my lib, tested and SWF still appears to be working fine without it. But again, when exporting to SWC - it didn't stack overflow, but this time my library errors out with "can't find codec".
I have 3 variants of the code actually - SWF, SWC and one executable which produces a real .mpg file so I can have better proof than "encoding frame X". And it still produces a good mpeg when executd from cygwin's command line. The only problem is the SWC.
My basic confusion is - why if SWF/executable  with the same libs etc. working fine, and then the SWC is failing on me? I'd really need to fix this somehow, but I don't understand the reasons, I thought once it's working in SWF it will work as SWC.

Answer 1

Ok, this is what I did
1) I've got the globalplayer 11.5 from Adobe's archive, copied it to the corresponding folder(right next to 11.1 which was already included in my Flex).
2) mxmlc -static-link-runtime-shared-libraries -compiler.omit-trace-statements=false -library-path=decoding_encoding.swc -debug=false Document.as -o swcdemo.swf -target-player=11.5 -swf-version=18 
Where decoding_encoding.swc is my former c library, Document.as only calls one function(the encoding one). This got me the swf.
3) I run this swf in debug player, in IE (11.6), and error is popping up.
In flashlog.txt I found this:
Encode virtual file             <-- this is entry point of my C function (all is fine so far, proof that it has been called)
Could not open codec            <-- FAIL again, this fails also in theora at a similar function (register codec context..huh?)
[object Exit]
          at global/com.ffmpeg::F__exit()
          at global/com.ffmpeg::F_exit()
          at global/com.ffmpeg::F_ffmpeg_encode_mpeg1()
          at global/com.ffmpeg::encode_mpeg1()
          at Document()
4)  I then go to my presumably failing C library, and change this in main:
//  AS3_GoAsync();    <-- I commented this
    ffmpeg_encode_mpeg1(AV_CODEC_ID_MPEG1VIDEO);   <-- I uncommented this
I launch the swf just to see if it also fails, but it goes like:
Encode virtual file
[mpeg1video @ 0x601410] Warning: not compiled with thread support, using thread emulation
Entering loop
etc..  
All works! So I really don't understand, how can it work in the emitted SWF while in emitted SWC it already doesn't work? Is there a different way the swc is built, is it the way it manages memory at runtime, being restricted somehow by the main SWF, or is it just some stupid switch or setting. I'd need to see a little deeper into how the SWC is build I guess to fully understand this issue. Do you have any isnight into this ilookha, or someone else?  Or perhaps any other idea.
I'm now trying to see if I can try to trace out the exact point of the issue in theora lib, basically I included AS3.h in their source code and now placing inline AS3 "trace" commands into the register codec function.
I have traced in theora's lib inside th_encode_alloc function where it fails, and located the first obvious reason:
  enc=_ogg_malloc(sizeof(*enc));
  if(enc==NULL) {
            inline_as3("trace('enc is NULL!');\n");  <-- my trace
I'm getting "enc is NULL". Which results into codec not found, because the whole function returns NULL. So it seems _ogg_malloc is failing to allocate memory. I bet the same reason goes for ffmpeg.  _ogg_malloc is:
#define _ogg_malloc  malloc
Just a normal malloc. Why wouldn't this work?