video - OpenCV : .avi file doesn't open with C++ API, opens with C -


could explain me why opencv fails open .avi file c++ api, instead opens c api ?

here 2 code snippets:

c++:

mat source; videocapture stream("video.avi");  if (!stream.isopened()){     std::cout << "stream cannot opened" << std::endl;     return -1; } while(1)      if(!stream.read(source)) {         std::cout << "error reading video frame" << endl;     }  imshow("source", source);

this fails open video.avi, , "error reading video frame" printed time after time. ffmpeg.dll in path , have installed ffdshow.

c:

cvcapture* stream = cvcreatefilecapture( "video.avi" ); iplimage* source; while(1) {     source = cvqueryframe( stream );     if( !source ) printf("\n problem");     mat src(source);     imshow("source", src);     if(waitkey(1) >= 0) break; }

this opens video.avi no problem.

thanks !

ps. maybe it's worth mentioning video.avi created using opencv.

your c , c++ code not equal. code work:

int main( int argc, char** argv ) {     mat source;     videocapture stream("video.avi");      if (!stream.isopened())     {         std::cout << "stream cannot opened" << std::endl;         return -1;     }      while(1)     {         stream >> source;         if(source.empty())          {             std::cout << "error reading video frame" << endl;         }         imshow("source", source);         waitkey(20);     }     stream.release();     getchar(); }

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