How to setup jpeglib with MS Visual C++ 2010 Express

Question

I try to use the well known "jpeglib" now available in version 9.

Overview: I am a programming starter in C using MS Visual C++ 2010 Express and read a C-book finally. My goal is to compress a RGB(.bmp)-file into JPEG. So I downloaded the jpeglib (v9), read all the install and so on *.txt-files. It was possible to compile the C-files to get cjpeg.exe, djpeg.exe, jpeg.lib and so on.

After this success I tried to use the example.c to get deeper into the jpeg and to control the compression. -> It did not work. Then I tried to use the jpeglib included in OpenCV. Same non working result, while the OpenCV code samples are compiled successfully.

I googled lots of samples, problem solutions and tips how to use jpeglib. Most helpful information I found here. But in the result I was still not able to compile my own jpeg-tool or example.c (rewriting the write_JPEG_file() function ).

Question: What in the basics could be wrong, when every other programmer just uses #include "jpeglib.h" in their codes to run the jpeg functions successfully? For me including this file seems not to be enough. Because of that I have to ask you and to relaunch a one year old Question that also did not helped solving my probs. I can not give you a specific error message because of multiple attempts to solve those issues.

Here is my current MS-VC++2010 config for using OpenCV 2.4.6:

1. C/C++ -> General -> Additional Include Directories:
   • C:\opencv\build\include
   • C:\opencv\build\include\opencv
   • C:\opencv\build\include\opencv2
   • C:\opencv\include
   • C:\opencv\include\opencv
   • C:\opencv\include\opencv2
   • C:\opencv\3rdparty\libjpeg
2. Linker -> General -> Additional Library Directories:
   • C:\opencv\build\x86\vc10\lib
3. Linker -> Input -> Additional Dependencies:
   • opencv_core246d.lib
   • opencv_imgproc246d.lib
   • opencv_highgui246d.lib
   • opencv_ml246d.lib
   • opencv_video246d.lib
   • opencv_features2d246d.lib
   • opencv_calib3d246d.lib
   • opencv_objdetect246d.lib
   • opencv_contrib246d.lib
   • opencv_legacy246d.lib
   • opencv_flann246d.lib
   • jpeg.lib [this I added into C:\opencv\build\x86\vc10\lib]

At last some threads I have already read:

• Compressing IplImage to JPEG using libjpeg in OpenCV - 1
• Compressing IplImage to JPEG using libjpeg in OpenCV - 2
• Need help in reading JPEG file using libjpeg
• how can i use jpeg_mem_src, jpeg_mem_dest in libjpeg-turbo?

If there is something missing you want to know I will do my best to add this information!

EDIT - Some error messages:

1>jpeg_coder.obj : error LNK2001: unresolved external symbol ""unsigned char * image_buffer" (?image_buffer@@3PAEA)".

1>jpeg_coder.obj : error LNK2001: unresolved external symbol ""int image_height" (?image_height@@3HA)".

1>jpeg_coder.obj : error LNK2001: unresolved external symbol """int image_width" (?image_width@@3HA)".

First symbol should be typedefed in jpeglib.h as JSAMPLE FAR *JSAMPROW, second and third are defined in rdjpgcom.c as unsigned int image_height, image_width;

Maybe, with a lot of luck, I figured out what is need to be done to get jpeglib running. In the current state I have to check and double check whether my problem solution is correct or not. At this point thank you very much for your attention for my issues. As soon as I am sure with the solution I will post it.

Problem Solution: I did not setup OpenCV correctly for using jpeglib. The mistake I made was to link the wrong *.lib-file. The proper file for linking is libjpegd.lib. Too bad that jpeglib v6.2 is included in OpenCV 2.4.6 instead of v9. The hint to add HAVE_JPEG to use jpeglib functions inside OpenCV I ignored completely. For now the problem is solved.

Answer 1

Problem Solution: I did not setup OpenCV correctly for using jpeglib. The mistake I made was to link the wrong *.lib-file.

The proper file for linking is libjpegd.lib.

Too bad that jpeglib v6.2 is included in OpenCV 2.4.6 instead of v9. The hint to add HAVE_JPEG to use jpeglib functions inside OpenCV I ignored completely. Thanks to all who tried solving this issue. For now the problem is solved.