Hi,
I'm experimenting with the build script on AV Linux/Debian Squeeze 32bit, If I disable frei0r in the script the build succeeds however with frei0r enabled the script fails with this:
In file included from /usr/include/opencv/cxcore.h:1826:0,
from /usr/include/opencv/cv.h:58,
from filter/facebl0r/facebl0r.cpp:20:
/usr/include/opencv/cxcore.hpp:177:13: error: 'ptrdiff_t' does not name a type
/bin/sh ../libtool --tag=CXX --tag=disable-static --mode=link g++ -module -avoid-version -lm -export-dynamic -o addition.la -rpath /home/tester/kdenlive/20120713/lib/frei0r-1 addition.lo
In file included from /usr/include/opencv/cxcore.hpp:2307:0,
from /usr/include/opencv/cxcore.h:1826,
from /usr/include/opencv/cv.h:58,
from filter/facebl0r/facebl0r.cpp:20:
/usr/include/opencv/cxoperations.hpp:2043:15: error: 'ptrdiff_t' does not name a type
/usr/include/opencv/cxoperations.hpp:2591:31: error: 'ptrdiff_t' does not name a type
In file included from /usr/include/opencv/cxcore.hpp:2308:0,
from /usr/include/opencv/cxcore.h:1826,
from /usr/include/opencv/cv.h:58,
from filter/facebl0r/facebl0r.cpp:20:
/usr/include/opencv/cxmat.hpp: In member function 'void cv::Mat::locateROI(cv::Size&, cv::Point&) const':
/usr/include/opencv/cxmat.hpp:387:5: error: 'ptrdiff_t' was not declared in this scope
/usr/include/opencv/cxmat.hpp:387:5: note: suggested alternatives:
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/opencv/cxmat.hpp:387:15: error: expected ';' before 'delta1'
/usr/include/opencv/cxmat.hpp:389:9: error: 'delta1' was not declared in this scope
/usr/include/opencv/cxmat.hpp:398:31: error: 'delta2' was not declared in this scope
mv -f .deps/vectorscope_la-vectorscope.Tpo .deps/vectorscope_la-vectorscope.Plo
/bin/sh ../libtool --tag=CXX --tag=disable-static --mode=link g++ -module -avoid-version -lm -export-dynamic -o addition_alpha.la -rpath /home/tester/kdenlive/20120713/lib/frei0r-1 addition_alpha.lo
mv -f .deps/rgbparade_la-rgbparade.Tpo .deps/rgbparade_la-rgbparade.Plo
/bin/sh ../libtool --tag=CC --tag=disable-static --mode=link gcc -std=gnu99 -I../include -module -avoid-version -lm -export-dynamic -o alpha0ps.la -rpath /home/tester/kdenlive/20120713/lib/frei0r-1 alpha0ps.lo
/usr/include/opencv/cxmat.hpp: In member function 'cv::Point cv::MatConstIterator_<_Tp>::pos() const':
/usr/include/opencv/cxmat.hpp:3459:9: error: 'ptrdiff_t' was not declared in this scope
/usr/include/opencv/cxmat.hpp:3459:9: note: suggested alternatives:
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/opencv/cxmat.hpp:3459:19: error: expected ';' before 'ofs'
/usr/include/opencv/cxmat.hpp:3460:23: error: 'ofs' was not declared in this scope
/usr/include/opencv/cxmat.hpp:3460:66: error: expected ')' before 'y'
/usr/include/opencv/cxmat.hpp:3465:9: error: 'ptrdiff_t' was not declared in this scope
/usr/include/opencv/cxmat.hpp:3465:9: note: suggested alternatives:
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/opencv/cxmat.hpp:3465:19: error: expected ';' before 'ofs'
/usr/include/opencv/cxmat.hpp:3466:23: error: 'ofs' was not declared in this scope
libtool: link: g++ -shared -nostdlib /usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu/crti.o /usr/lib/gcc/i486-linux-gnu/4.6/crtbeginS.o .libs/addition.o -L/usr/lib/gcc/i486-linux-gnu/4.6 -L/usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu -L/usr/lib/gcc/i486-linux-gnu/4.6/../../../../lib -L/lib/i386-linux-gnu -L/lib/../lib -L/usr/lib/i386-linux-gnu -L/usr/lib/../lib -L/usr/lib/gcc/i486-linux-gnu/4.6/../../.. -lstdc++ -lm -lc -lgcc_s /usr/lib/gcc/i486-linux-gnu/4.6/crtendS.o /usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu/crtn.o -Wl,-soname -Wl,addition.so -o .libs/addition.so
In file included from /usr/include/opencv/cxcore.h:1826:0,
from /usr/include/opencv/cv.h:58,
from filter/facedetect/facedetect.cpp:28:
/usr/include/opencv/cxcore.hpp:177:13: error: 'ptrdiff_t' does not name a type
libtool: link: gcc -std=gnu99 -shared .libs/alpha0ps.o -lm -Wl,-soname -Wl,alpha0ps.so -o .libs/alpha0ps.so
libtool: link: ( cd ".libs" && rm -f "addition.la" && ln -s "../addition.la" "addition.la" )
/bin/sh ../libtool --tag=CXX --tag=disable-static --mode=link g++ -module -avoid-version -lm -export-dynamic -o alphaatop.la -rpath /home/tester/kdenlive/20120713/lib/frei0r-1 alphaatop.lo
libtool: link: g++ -shared -nostdlib /usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu/crti.o /usr/lib/gcc/i486-linux-gnu/4.6/crtbeginS.o .libs/addition_alpha.o -L/usr/lib/gcc/i486-linux-gnu/4.6 -L/usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu -L/usr/lib/gcc/i486-linux-gnu/4.6/../../../../lib -L/lib/i386-linux-gnu -L/lib/../lib -L/usr/lib/i386-linux-gnu -L/usr/lib/../lib -L/usr/lib/gcc/i486-linux-gnu/4.6/../../.. -lstdc++ -lm -lc -lgcc_s /usr/lib/gcc/i486-linux-gnu/4.6/crtendS.o /usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu/crtn.o -Wl,-soname -Wl,addition_alpha.so -o .libs/addition_alpha.so
libtool: link: ( cd ".libs" && rm -f "alpha0ps.la" && ln -s "../alpha0ps.la" "alpha0ps.la" )
/bin/sh ../libtool --tag=CC --tag=disable-static --mode=link gcc -std=gnu99 -I../include -module -avoid-version -lm -export-dynamic -o alphagrad.la -rpath /home/tester/kdenlive/20120713/lib/frei0r-1 alphagrad.lo
In file included from /usr/include/opencv/cxcore.hpp:2307:0,
from /usr/include/opencv/cxcore.h:1826,
from /usr/include/opencv/cv.h:58,
from filter/facedetect/facedetect.cpp:28:
/usr/include/opencv/cxoperations.hpp:2043:15: error: 'ptrdiff_t' does not name a type
make[1]: *** [facebl0r.lo] Error 1
make[1]: *** Waiting for unfinished jobs....
libtool: link: ( cd ".libs" && rm -f "addition_alpha.la" && ln -s "../addition_alpha.la" "addition_alpha.la" )
/usr/include/opencv/cxoperations.hpp:2591:31: error: 'ptrdiff_t' does not name a type
In file included from /usr/include/opencv/cxcore.hpp:2308:0,
from /usr/include/opencv/cxcore.h:1826,
from /usr/include/opencv/cv.h:58,
from filter/facedetect/facedetect.cpp:28:
/usr/include/opencv/cxmat.hpp: In member function 'void cv::Mat::locateROI(cv::Size&, cv::Point&) const':
/usr/include/opencv/cxmat.hpp:387:5: error: 'ptrdiff_t' was not declared in this scope
/usr/include/opencv/cxmat.hpp:387:5: note: suggested alternatives:
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/opencv/cxmat.hpp:387:15: error: expected ';' before 'delta1'
/usr/include/opencv/cxmat.hpp:389:9: error: 'delta1' was not declared in this scope
/usr/include/opencv/cxmat.hpp:398:31: error: 'delta2' was not declared in this scope
libtool: link: gcc -std=gnu99 -shared .libs/alphagrad.o -lm -Wl,-soname -Wl,alphagrad.so -o .libs/alphagrad.so
libtool: link: ( cd ".libs" && rm -f "alphagrad.la" && ln -s "../alphagrad.la" "alphagrad.la" )
libtool: link: g++ -shared -nostdlib /usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu/crti.o /usr/lib/gcc/i486-linux-gnu/4.6/crtbeginS.o .libs/alphaatop.o -L/usr/lib/gcc/i486-linux-gnu/4.6 -L/usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu -L/usr/lib/gcc/i486-linux-gnu/4.6/../../../../lib -L/lib/i386-linux-gnu -L/lib/../lib -L/usr/lib/i386-linux-gnu -L/usr/lib/../lib -L/usr/lib/gcc/i486-linux-gnu/4.6/../../.. -lstdc++ -lm -lc -lgcc_s /usr/lib/gcc/i486-linux-gnu/4.6/crtendS.o /usr/lib/gcc/i486-linux-gnu/4.6/../../../i386-linux-gnu/crtn.o -Wl,-soname -Wl,alphaatop.so -o .libs/alphaatop.so
/usr/include/opencv/cxmat.hpp: In member function 'cv::Point cv::MatConstIterator_<_Tp>::pos() const':
/usr/include/opencv/cxmat.hpp:3459:9: error: 'ptrdiff_t' was not declared in this scope
/usr/include/opencv/cxmat.hpp:3459:9: note: suggested alternatives:
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/opencv/cxmat.hpp:3459:19: error: expected ';' before 'ofs'
/usr/include/opencv/cxmat.hpp:3460:23: error: 'ofs' was not declared in this scope
/usr/include/opencv/cxmat.hpp:3460:66: error: expected ')' before 'y'
/usr/include/opencv/cxmat.hpp:3465:9: error: 'ptrdiff_t' was not declared in this scope
/usr/include/opencv/cxmat.hpp:3465:9: note: suggested alternatives:
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/c++/4.6/i486-linux-gnu/./bits/c++config.h:156:28: note: 'std::ptrdiff_t'
/usr/include/opencv/cxmat.hpp:3465:19: error: expected ';' before 'ofs'
/usr/include/opencv/cxmat.hpp:3466:23: error: 'ofs' was not declared in this scope
libtool: link: ( cd ".libs" && rm -f "alphaatop.la" && ln -s "../alphaatop.la" "alphaatop.la" )
make[1]: *** [facedetect.lo] Error 1
make[1]: Leaving directory `/home/tester/kdenlive/src/frei0r/src'
make: *** [all-recursive] Error 1
ERROR: Unable to build frei0r
LOG: Process has finished. Reason: FAILURE Some kind of error occured: Unable to build frei0r
tester@av6devdesk:~$
To my knowledge all dev libs are installed. Help or advice appreciated!

Hi,
Problem caused by OpenCV 2.1 on Debian Squeeze being too old. Building opencv 2.4.2 from source fixed the compilation error, thread marked as solved.