I am developing a custom Youtube video player. But I am not able to compile the program. I am missing something in Makefile. My program looks like
main.c
#include<gdata/services/youtube/gdata-youtube-service.h>
int main(int argc, char **argv[])
{
printf("Youtube Application\n");
return 0;
}
makefile
gcc `pkg-config --cflags --libs libgdata-google-1.2` -lgdata-google-1.2 main.c -o youtube
When I compile, it is giving error like
error: gdata/services/youtube/gdata-youtube-service.h: No such file or directory
Do I got to install some other packages ? Or, i need to include something in my Makefile ?
Are you on Debian/Ubuntu? You probably want the libgdata-dev package.
$ apt-file search gdata/services/youtube/gdata-youtube-service.h
libgdata-dev: /usr/include/libgdata/gdata/services/youtube/gdata-youtube-service.h
Tried compiling it too, and tried using one of the methods declared in gdata-youtube-service.h
$ gcc `pkg-config --cflags --libs libgdata` main.c -o yt
$ ./yt
Youtube Application
Related
I'm working remotely on Linux operating system, where I'm trying to compile a .cu file.
The folder contains a main.cu file which does an histogram equalization. It uses opencv libraries.
How should I create the makefile? Everything I tried didn't work.
I got this error: undefined reference to cv::imread(cv::String const&, int)'
Is this the right way to make a makefile?
BINARY=cuda
SOURCES= main.cu
LIBPATHS = /usr/include/opencv2/libopencv_highgui.so
CC=nvcc
OBJECTS=$(SOURCES:.cu=.o)
INCFLAGS=$(foreach TMP,$(INCPATHS),-I$(TMP))
LIBFLAGS=$(foreach TMP,$(LIBPATHS),-L$(TMP))
OPENCV = `pkg-config opencv --cflags --libs`
LIBS = $(OPENCV)
$(PROG):$(SRCS)
$(CC) $(CFLAGS) -o $(PROG) $(SRCS) $(LIBS)
all:
$(CC) $(INCFLAGS) $(SOURCES) -o $(BINARY)
distclean:
rm -f $(BINARY)
clean:
rm -f $(BINARY)
I got these two include in my main.cu file:
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
Thanks a lot
I am trying to compile a short test program that requires Qt4, but have trouble properly linking to the Qt4 library. I have installed Qt4 via
sudo apt-get install qt4-dev-tools
The program code looks like this
#include <QtCore>
#include <iostream>
int main() {
std::cout << "Qt version: " << qVersion() << std::endl;
}
The shared library libQtCore.so is at /usr/lib/x86_64-linux-gnu but trying to compile the following way
g++ -L/usr/lib/x86_64-linux-gnu -Wall -o test.exe test.cpp -lQtCore
returns an error message that there is no file or directory called QtCore.
I have also tried to directly use the QtCore source code, but have received the following error message:
/tmp/ccljEHOY.o: In function main':
test.cpp:(.text+0xa): undefined reference toqVersion()'
collect2: error: ld returned 1 exit status
What am I doing wrong here?
Thanks
Ips
The compiler was not able to find QtCore file because you need to add path with Qt to the list of directories to be searched for header files.
You can use the pkg-config to get proper flags:
$:pkg-config QtCore --cflags
-DQT_SHARED -I/usr/include/qt4 -I/usr/include/qt4/QtCore
For linking:
$:pkg-config QtCore --libs
-lQtCore
You can use pkg-config when calling the compiler:
g++ test.cpp `pkg-config QtCore --cflags --libs`
or
g++ `pkg-config QtCore --cflags` test.cpp `pkg-config QtCore --libs`
Note that the following way won't work:
g++ `pkg-config QtCore --cflags --libs` test.cpp
#include <opencv2/opencv.hpp> //头文件
using namespace cv; //包含cv命名空间
int main()
{
Mat img=imread("cornea.jpg");
imshow("src",img);
waitKey(0);
return 0;
}
And I compile it with:
g++ test.cpp -o test pkg-config opencv --cflags --libs opencv
Which gives me:
/usr/bin/ld: warning: libicui18n.so.54, needed by //home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5, not found (try using -rpath or -rpath-link)<br/>
/usr/bin/ld: warning: libicuuc.so.54, needed by //home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5, not found (try using -rpath or -rpath-link)<br/>
/usr/bin/ld: warning: libicudata.so.54, needed by //home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5, not found (try using -rpath or -rpath-link)<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_clone_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘uenum_next_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘u_strToLower_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getStandardName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_setAttribute_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_setMillis_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_strcoll_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_setSubstChars_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_getTimeZoneDisplayName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_openCountryTimeZones_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_fromUnicode_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_open_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getDefaultName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_open_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_close_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_inDaylightTime_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_getSortKey_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getAvailableName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_close_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_get_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_openTimeZoneIDEnumeration_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_getDSTSavings_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_open_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_openTimeZones_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_toUnicode_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘u_strToUpper_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘u_errorName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_close_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘uenum_close_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_countAvailable_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getMaxCharSize_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getAlias_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_getDefaultTimeZone_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_compareNames_54’未定义的引用<br/>
collect2: error: ld returned 1 exit status
The backticks in command line pkg-config opencv --cflags --libs opencv is invisible. I have not got the reason now.
Indeed,in early days, I have installed Qt. But now, I do not want my program have something to do with Qt. In order that my program is not affected by the Qt library function, I shielded the path variables of Qt in the /etc/bash.bashrc file and installed a new gcc of 5.3.0. But the same error is still existing!
I'm using Ubuntu 14.04
Download ICU-54.1 from here
http://www.linuxfromscratch.org/blfs/view/7.7/general/icu.html
and install manually.
For me this solved the problem.
I have written an OpenCV program which contains both main.cpp and pedestrian.cpp. I wanted to compile them, so I did the following:
g++ -c -Wall `pkg-config --cflags opencv` main.cpp -o main.o
g++ -c -Wall `pkg-config --cflags opencv` pedestrian.cpp -o pedestrian.o
g++ `pkg-config --libs opencv` pedestrian.o main.o -o detect
After the third statement, every OpenCV command I use is considered an undefined reference. I have no idea why this is happening since other single object programs work just fine with pkg-config. I checked to see if it was a namespace problem and it wasn't either. Any help would be greatly appreciated.
Try changing the order int the last line to:
g++ -o detect pedestrian.o main.o `pkg-config --libs opencv`
This should work. Order matters when linking the .o files. When the linker finds and unknown OpenCV symbol in any of the .o, it looks for its definition in the following linked elements (i.e. in the elements to the right).
I am learning OpenCV using Learning OpenCV book.
One problem I am facing while compiling the code is that I have to write a long command to compile and get the executable.
This is the command I am using
g++ `pkg-config –cflags opencv` file_name.cpp -o output_file `pkg-config –libs opencv`
I am no Make expert but I think I can eliminate writing that long command using make.
Before that I should explain my work flow. I have created a directory called opencv in my home directory (~/opencv/). I am reading the book section by section and coding the examples or exercises into new cpp source code files in that directory. So I don't know the names of the files before hand.
Now what I want make to do is,
Suppose I have coded a new file named facedetect.cpp in my opencv directory, and if I call make like this
make facedetect
then I want make to execute the following command for me
g++ `pkg-config --cflags opencv` facedetect.cpp -o facedetect `pkg-config --libs opencv`
so that whenever I make a new file named abc.cpp, I will execute make abc
so that I can run
$ ./abc
at my command line to test my abc.cpp
Please give that make file so that I can save the frustration of typing that long command each time.
PS: I have Googled for help on this and found this on using CMake but I could not understand what that does. Kindly also explain how can I use CMake for the same task.
You can create a file called Makefile in you working directory like this:
CFLAGS = `pkg-config --cflags opencv`
LIBS = `pkg-config --libs opencv`
% : %.cpp
g++ $(CFLAGS) $(LIBS) -o $# $<
then you can use this file for all your single-file programms. Just call make with the basename of the file you want to compile. For facedetect.cpp that would be
make facedetect
Here some more details:
The general format of a makefile is like this:
target : dependecy1 dependenc2 ...
command that generates the target
So for your example you could write:
facedetect : facedetect.cpp
g++ $(CFLAGS) $(LIBS) -o facedetect facedetect.cpp
For each new example you can now create a new target. But you can also make it more general:
% : %.cpp
g++ $(CFLAGS) $(LIBS) -o $# $<
Here % matches any nonempty substring. The automatic variables $# and $< substitute the names of the target file and the source file.
For more information you can consult the make documentation.
GNU Make is pretty smart and the Makefile you need for this doesn't need to be as verbose as in the other answers given so far. Here is a simple Makefile which you can use to compile the OpenCV examples:
CPPFLAGS = $(shell pkg-config --cflags opencv)
LDLIBS = $(shell pkg-config --libs opencv)
That's it. The Makefile can be this short thanks to Make's implicit rules.
Then run make as usual:
make facedetect
This assumes there is a facedetect.c or facedetect.cpp in the same directory.
I recommend the following (free!) book if you want to learn Make: http://oreilly.com/catalog/make3/book/index.csp
Create a file named makefile in your working directory that contains the following:
CFLAGS = $SHELL(pkg-config --cflags opencv)
LIBS = $SHELL(pkg-config --libs opencv)
facedetect : facedetect.cpp
g++ $(CFLAGS) $(LIBS) -o $# $<
Then when you want to compile you just type:
$ make
(To answer your PS - note that CMake is very different from make - for now you should probaby just use make.)