How to use the libpng in Qt Widgets Application？
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I want to use libpng in iOS and mac.
I know that Qt integration libpng，but I can‘t find it.⊙▽⊙
Where is libpng's .h file in QtSDK?
My QtSDK version is 5.5
THX.. -
Qt doesn't expose those, as one is expected to use the Qt's own image
classes. As for every other 3rdparty library, none of the headers are shipped
and as far as I know most of if not all of the stuff is linked statically to the
appropriate qt library by default. -
@Huulivoide
Thanks for your posts.
I am using libpng source file that is download from libpng site in my project.
But there are many redefine errors in iOS , like this:===================
duplicate symbol _png_set_sig_bytes in:
/Users/goldlion/Documents/workspace/Qt/build-qt_opengles2-iphonesimulator_clang_Qt_5_5_0_for_iOS-Debug/qt_opengles2.build/Debug-iphonesimulator/qt_opengles2.build/Objects-normal/i386/png.o
/Applications/Qt5.5.0/5.5/ios/lib/libQt5Gui_iphonesimulator_debug.a(png.o)
duplicate symbol _png_sig_cmp in:
/Users/goldlion/Documents/workspace/Qt/build-qt_opengles2-iphonesimulator_clang_Qt_5_5_0_for_iOS-Debug/qt_opengles2.build/Debug-iphonesimulator/qt_opengles2.build/Objects-normal/i386/png.o
/Applications/Qt5.5.0/5.5/ios/lib/libQt5Gui_iphonesimulator_debug.a(png.o)
duplicate symbol _png_zalloc in:
/Users/goldlion/Documents/workspace/Qt/build-qt_opengles2-iphonesimulator_clang_Qt_5_5_0_for_iOS-Debug/qt_opengles2.build/Debug-iphonesimulator/qt_opengles2.build/Objects-normal/i386/png.o
/Applications/Qt5.5.0/5.5/ios/lib/libQt5Gui_iphonesimulator_debug.a(png.o)
duplicate symbol _png_zfree in:
...And it works good in mac.⊙▽⊙
But they are one same project. -
Hi and welcome to devnet,
The only place you'll find libpng with Qt is in the sources. It fails on iOS because iOS is a static build so it already contains all the symbols of the jpeg library it uses.
