I'm developing an application to capture video from webcam and stream it to Android. I'm using ffmpeg latest release - 2.5.2 "Bohr" on Ubuntu 14.04 32bit and using Eclipse as IDE.
I'm receiving this error when compiling:
g++ -L/usr/local/lib -L/home/idanhahn/ffmpeg/ffmpeg_build/lib -o "camera" ./src/.metadata/.plugins/org.eclipse.cdt.make.core/specs.o ./src/CameraSec.o ./src/camera.o ./.metadata/.plugins/org.eclipse.cdt.make.core/specs.o -lz -lswscale -lopencv_core -lavcodec -lavutil -lpthread -lboost_thread -lboost_system -lboost_date_time -lopencv_imgproc -lopencv_highgui -lopencv_ml -lopencv_video -lopencv_features2d -lopencv_calib3d -lopencv_objdetect -lopencv_contrib -lopencv_legacy -lopencv_flann -lavformat
/usr/bin/ld: /home/idanhahn/ffmpeg/ffmpeg_build/lib/libavformat.a(http.o): undefined reference to symbol 'inflateInit2_'
/usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libz.so: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
I've linked avformat (and other ffmpeg related libs).
I've tried the following:
Linked libz.
Tried to recompile using instructions from here: http://trac.ffmpeg.org/wiki/CompilationGuide/Ubuntu
What could be the problem?
Why linker points to i686 and then go back to i386?
You are really only missing an additional library here. Just add -llzma to the end of your compilation line.
I additionally had to add other missing libraries. Just append in case you are facing the same problem:
-lswresample -lm -lz
It is because libavcodec includes some math and zlib headers, so you must link to the respective libraries as well. This is also the case for lzma.
then you need to put -llzma with the compilation line of ffmpeg.
or i have an alternative to do it via simpler method.
Try this: http://ubuntuforums.org/showthread.php?t=2219550&p=13101922#post13101922
it will be simple..
Related
First time I cannot compile hello world.
I've followed tons of tutorials how to install opencv.
I just have following example:
#include <iostream>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
using namespace std;
using namespace cv;
int main()
{
Mat imageMe = imread("test.jpg", 0);
return 0;
}
from opencv website.
Looks straightforward, but it won't compile.
g++ display_image.cpp `pkg-config --cflags --libs opencv` -l
Here's the error:
display_image.cpp:2:10: fatal error: 'opencv2/core/core.hpp' file not found
#include <opencv2/core/core.hpp>
^
1 error generated.
And running:
pkg-config --cflags --libs opencv
return this:
-I/usr/local/Cellar/opencv3/3.2.0/include/opencv -I/usr/local/Cellar/opencv3/3.2.0/include/opencv2 -L/usr/local/Cellar/opencv3/3.2.0/lib -lopencv_calib3d -lopencv_imgproc -lopencv_contrib -lopencv_legacy -l
these files are present.
Running ls /usr/local/Cellar/opencv3/3.2.0/include/opencv2/core | grep core.hpp
Gives the result:
core.hpp
What's the problem?
edit:
I've been using following tutorials to install opencv on my machine:
http://www.pyimagesearch.com/2016/12/19/install-opencv-3-on-macos-with-homebrew-the-easy-way/
https://www.learnopencv.com/install-opencv-3-on-yosemite-osx-10-10-x/
https://blogs.wcode.org/2014/10/howto-install-build-and-use-opencv-macosx-10-10/
http://seeb0h.github.io/howto/howto-install-homebrew-python-opencv-osx-el-capitan/
edit:
Even after all these answers I cannot compile a single app. Even if it somehow can find .hpp file directly included in my file it fails finding includes inside.
Probably my configuration is wrong.
In /usr/local/Cellar/opencv3 I have 2 directories:
3.2.0 - probably installed binaries
HEAD-9053839 - compiled from source
Now I also have opencv.pc file located in /usr/local/lib/pkgconfig:
prefix=/usr/local/Cellar/opencv3/3.2.0
exec_prefix=${prefix}
includedir=${prefix}/include
libdir=${exec_prefix}/lib
Name: opencv
Description: The opencv library
Version: 2.x.x
Cflags: -I${includedir}/opencv -I${includedir}/opencv2
Libs: -L${libdir} -lopencv_calib3d -lopencv_imgproc -lopencv_contrib -lopencv_legacy -l
As a prefix I've also tried HEAD-9053839.
I've created even simplier example:
#include <opencv2/opencv.hpp>
int main(){return 0; }
It's still telling me that 'opencv2/opencv.hpp' file not found.
Then I printed what pkg-config says:
pkg-config --cflags --libs opencv
-I/usr/local/Cellar/opencv3/3.2.0/include/opencv -I/usr/local/Cellar/opencv3/3.2.0/include/opencv2 -L/usr/local/Cellar/opencv3/3.2.0/lib -lopencv_calib3d -lopencv_imgproc -lopencv_contrib -lopencv_legacy -l
And found out it'd rather should be directly include dir, not opencv/opencv2 subdirectories.
So I've ran g++ like this:
g++ -I/usr/local/Cellar/opencv3/3.2.0/include -L/usr/local/Cellar/opencv3/3.2.0/lib -lopencv_calib3d -lopencv_imgproc -lopencv_contrib -lopencv_legacy -l display_image.cpp
Then it told me:
ld: library not found for -lopencv_contrib
After removing it it said:
ld: library not found for -lopencv_legacy
Then I had to remove -l before display_image.cpp, but then I've got another error:
Undefined symbols for architecture x86_64:
"cv::String::deallocate()", referenced from:
cv::String::~String() in display_image-9d8f86.o
cv::String::operator=(cv::String const&) in display_image-9d8f86.o
This is hell.
I don't have a compilation environment to regenerate your error but I think the problem is about these lines in your code:
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
since the opencv directory is being searched from
/usr/local/Cellar/opencv3/3.2.0/include/opencv2
as your "pkg-config --cflags --libs opencv" implies. So, I suppose, changing the include lines into
#include <core/core.hpp>
#include <highgui/highgui.hpp>
would help, or you can implicitly declare the directory you want to search like this:
g++ -I/usr/local/Cellar/opencv3/3.2.0/include display_image.cpp ...
In OpenCV 3.x, the layout of the header files has changed and now you pretty much just use:
#include <opencv2/opencv.hpp>
So, in concrete terms, I am suggesting you replace your 2nd and 3rd lines with the above incantation.
See the OpenCV Transition Guide.
Soner's answer should solve the OP's problem. I want to add some other solutions.
If you use CMake to install openCV from source, it will put OpenCV libraries in /usr/local/lib and OpenCV headers in /usr/local/include. Where the headers all go in the subfolder /usr/local/include/opencv. Since they are default library and header directories for most IDE's, all the examples you find will work with that config.
Now, brew does not install OpenCV to the above folders as you already knew. So you have three options:
Change compiler's search paths for OpenCV libraries and headers: g++ -I/usr/local/Cellar/opencv3/3.2.0/include -L/usr/local/Cellar/opencv3/3.2.0/lib
Soft link /usr/local/Cellar/opencv3/3.2.0/include/opencv to /usr/local/include and /usr/local/Cellar/opencv3/3.2.0/lib to /usr/local/lib
Install OpenCV from source with CMake.
I did it!
It was a problem with pkg-config.
In /usr/local/Cellar/opencv3/3.2.0/lib/pkgconfig I've found opencv.pc, which looks like this:
# Package Information for pkg-config
prefix=/usr/local/Cellar/opencv3/3.2.0
exec_prefix=${prefix}
libdir=${exec_prefix}/lib
includedir_old=${prefix}/include/opencv
includedir_new=${prefix}/include
Name: OpenCV
Description: Open Source Computer Vision Library
Version: 3.2.0
Libs: -L${exec_prefix}/lib -lopencv_shape -lopencv_stitching -lopencv_objdetect -lopencv_superres -lopencv_videostab -lopencv_calib3d -lopencv_features2d -lopencv_highgui -lopencv_videoio -lopencv_imgcodecs -lopencv_video -lopencv_photo -lopencv_ml -lopencv_imgproc -lopencv_flann -lopencv_core
Libs.private: -framework OpenCL -L/usr/local/opt/jpeg/lib -ljpeg -L/usr/local/lib -lpng -ltiff -lImath -lIlmImf -lIex -lHalf -lIlmThread -L/usr/lib -lz -framework Cocoa -framework AVFoundation -framework CoreGraphics -framework CoreMedia -framework CoreVideo -framework QuartzCore -framework Accelerate
Cflags: -I${includedir_old} -I${includedir_new}
I've replaced old opencv.pc located in: /usr/local/lib/pkgconfig
Now I'm not getting any errors.
I also had to use different include file:
#include <opencv2/opencv.hpp>
I am new to C++, openCV and Artoolkit
I am trying to build a motion tracker devices
right now, I am following the tutorial
https://artoolkit.org/blog/2016/05/opencv-with-artoolkit
However I meet some problem when I trying to implement this on SimpleTest on the Linux machine.
The error I get is like this:
"clang++ -c -O3 -fPIC -march=core2 -DHAVE_NFT=1 -I/usr/include/x86_64-linux-gnu -pthread -I/usr/include/gstreamer-0.10 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/libxml2 -I../../include simpleTest.c
clang: warning: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated In file included from simpleTest.c:79: In file included from ../../include/linux-x86_64/opencv2/opencv.hpp:59:/usr/include/opencv2/contrib/contrib.hpp:273:23: error: no template named
'vector'; did you mean 'std::vector'?"
simpleTest code
I added line like this
#include <linux-x86_64/opencv2/opencv.hpp>
#include <linux-x86_64/opencv2/opencv_modules.hpp>
using namespace std;
using namespace cv;
in the make file:
I add some this:
LIBS= -lARgsub -lARvideo -lAR -lARICP -lAR -lglut -lGLU -lGL -lX11 -lm -lpthread -ljpeg -pthread -lgstreamer-0.10 -lgobject-2.0 -lgmodule-2.0 -lgthread-2.0 -lxml2 -lglib-2.0 -ldc1394 -lraw1394 -lopencv_shape -lopencv_stitching -lopencv_objdetect -lopencv_superres -lopencv_videostab -lopencv_calib3d -lopencv_features2d -lopencv_highgui -lopencv_videoio -lopencv_imgcodecs -lopencv_video -lopencv_photo -lopencv_ml -lopencv_imgproc -lopencv_flann -lopencv_viz -lippicv -lopencv_core
and
CC = clang++
There are some similar issues found on SO here.....
Linking C from C++ in OS X Mavericks
Warning: treating 'c-header' input as 'c++-header' when in C++ mode, this behavior is deprecated
There's a mismatch between C++ and C.
To get around this, it would be best if you used ARWrapper for ARToolkit within a C++ framework.
So I've written some very basic OpenCV C++ code to test it's functionality. I am using CodeBlocks on Linux Ubuntu 16.04. I have installed OpenCV correctly, I think, Codeblocks offers 'OpenCV Project' as an option when making a project and whenever I start typing in an OpenCV keyword, it'll expand and suggest keywords.
My problem is that when I attempt to build it, I get
undefined reference to `cv::imread(std::__cxxll::basic_string<char, std::char_traits<ch..
And it repeats this for every opencv function.
I read somewhere that this may have something to do with the archive files and so I'll provide the results when I enter:
pkg-config opencv --libs
into the terminal. The output is:
-L/usr/local/lib -lopencv_calib3d -lopencv_contrib -lopencv_core
-lopencv_features2d -lopencv_flann -lopencv_gpu -lopencv_highgui
-lopencv_imgproc -lopencv_legacy -lopencv_ml -lopencv_nonfree
-lopencv_objdetect -lopencv_ocl -lopencv_photo -lopencv_stitching
-lopencv_superres -lopencv_ts -lopencv_video -lopencv_videostab -latomic
-ltbb -lGL -lGLU -lrt -lpthread -lm -ldl
So how can I solve this issue? Should I edit my files in some way?
Thanks very much in advance
Your code has been compiled with a standard library using the std::__cxx11 namespace. Ie, you're probably using g++ 5+ which has a different ABI to previous versions. The opencv libraries you've installed are probably an older ABI, and therefore not compatible.
You can either compile the opencv libraries yourself, use an earlier compiler that matches the ABI of the libries you have, or configure your compiler to use the old ABI.
You can use the macro _GLIBCXX_USE_CXX11_ABI if you're using g++ 5. Before you include and std libs:
#define _GLIBCXX_USE_CXX11_ABI 0
Recently I build opencv as static library(by using BUILD_SHARED_LIBS=OFF) while dynamic libraries are already there, but at different location. And when I build may program I am getting many error. I am using command line for compiling the code, and look like below.
g++ -static -I$(OpenCV_Static_Build)/include/opencv -L$(OpenCV_Static_Build)/lib/ -g -o binary main.cpp -lopencv_core -lopencv_imgproc -lopencv_highgui -lopencv_ml -lopencv_video -lopencv_features2d -lopencv_calib3d -lopencv_objdetect -lopencv_contrib -lopencv_legacy
The error look like,
grfmt_tiff.cpp:(.text._ZN2cv11TiffEncoder12writeLibTiffERKNS_3MatERKSt6vectorIiSaIiEE+0x167): undefined reference to `TIFFSetField'
window_gtk.cpp:(.text.cvNamedWindow+0x29d): undefined reference to `g_type_check_instance_cast'
/usr/lib/gcc/i486-linux-gnu/4.4.3/libgcc_eh.a(unwind-dw2.o): In function `uw_init_context_1':
(.text+0x22f8): undefined reference to `pthread_once'
Those errors don't come from OpenCV (as one can tell from the function names) but from GLib and libpthread. Use the -lglib-2.0 -lpthread linker flags.
I'm trying to compile a sample program after installing Opencv with the command:
g++ hello-world.cpp -o hello-world -I /usr/local/include/opencv -L /usr/local/lib -lm -lcv -lhighgui -lcvaux
however, I'm getting an error that says:
/usr/bin/ld: cannot find -lcv
/usr/bin/ld: cannot find -lhighgui
/uer/bin/ld: cannot find -lcvaux
collect2: ld returned 1 exit status
What do I need to do to correct this?? I installed opencv by downloading the latest stable version and using cmake to create the build files, then ran make install from the command line.
Was there anything I may have missed?
UPDATED-
Better use this command:
g++ opencv.cpp -o opencv -L `pkg-config --cflags --libs opencv`
The pkg-config command will locate the correct include and library for your source code.
For better handling with OpenCV programming go with an IDE like code::block.
Maybe this tutorial will help you in OpenCV programming with code::block:
How to Setup OpenCV for code :: block in Linux and Windows?
Recently I started using OpenCV and I got similar problem and for me this works really well:
-lopencv_core -lopencv_imgproc -lopencv_highgui -lopencv_objdetect
Hope it will solve your problem.
You need to add another -L argument specifying the actual location of the OpenCV libraries.