dlib C++ Library / Discussion / Help: Unable to load jpeg unless I include all the files under libjpeg

Sagar B Hathwar - 2016-06-02

Hey,

Here are my OS, Compiler and other details
OS - Windows 10 64 bit
Compiler - Visual Studio 2015 Win64
Static or Shared library - Shared

First I compiled Opencv, then dlib. After compiling opencv, I obtained libjpeg.lio in my 3dparty folder. OpenCV works fine with it but dlib just doesnt. I also defined DLIB_JPEG_SUPPORT globally, but the compiler complains that it cannot find libjpeg.h!
I defined DLIB_JPEG_SHARED, this time, I get
"Exception thrown!
You must #define DLIB_JPEG_SUPPORT and link to libjpeg to read JPEG files.
Do this by following the instructions at http://dlib.net/compile.html."

Then I included all the files under external\libjpeg and only then it works.

Problem is everything compiles again and again making compilation so slow
Is there a better way of creating a libjpeg.lib or dll so that I need not compile it again and again?

Thanks

If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
- Davis - 2016-06-02
  
  Visual studio will only recompile files if they change or you deliberately
  tell it to clean the project and rebuild everything. So if you let it do
  normal incremental builds you won't have build time problems.
  
  If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
  - Sagar B Hathwar - 2016-06-03
    
    Guess that's fine
    
    One question though, why doesn't the jpeglib.lib compiled with opencv work with dlib?
    
    If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
    - Davis - 2016-06-03
      
      It works fine if you put the header files for that version of libjpeg in your compiler's include search path.
      
      If you would like to refer to this comment somewhere else in this project, copy and paste the following link:

raffic maleo - 2017-07-14

Hello,
I am new to C++ and using MINGW 64 on windows 8 to compile this

g++ -static -static-libgcc -static-libstdc++ -std=c++11 -O3 -I.. ../dlib/all/source.cpp -I.. -luser32 -lws2_32 -lgdi32 -lcomctl32 -limm32 -lpthread -lkernel32 -ladvapi32 -lshell32 -lmsvcrt -lwinmm -ldxguid -lz -DDLIB_JPEG_SUPPORT -DDLIB_PNG_SUPPORT my_ex.cpp

i am getting this error
../dlib/all/../image_loader/png_loader.cpp:13:17: fatal error: png.h: No such fi
le or directory #include <png.h></png.h>

How do i use the source directory of the libpng and libjpeg in the dlib/external/ folder in the gcc command line.

If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
- Davis - 2017-07-14
  
  If you are new to C++ then use cmake. http://dlib.net/compile.html tells
  you what to type.
  
  If you would like to refer to this comment somewhere else in this project, copy and paste the following link:

Unable to load jpeg unless I include all the files under libjpeg

Forums

Help

Unable to load jpeg unless I include all the files under libjpeg document.SUBSCRIPTION_OPTIONS = { "thing": "topic", "subscribed": false, "url": "subscribe", "icon": { "css": "fa fa-envelope-o" } };

Unable to load jpeg unless I include all the files under libjpeg