Joger, I’ve been able to build Qt statically from source with FFmpeg support.
But when trying to run a simple multimedia application from Qt Creator, when compiling it complains with linker errors. It seems that a lot of libraries are not being passed to the linker. Do you think this is because during Qt build I passed a FFmpeg directory that had both dynamic libs and statically libs of FFMpeg and the dynamic libraries have been chosen in first place? I’ve also been able to create a script to build FFmpeg from source on macOS. I would be interested in knowing what flags should be enabled in order to take the most out of the FFmpeg backend. Some other questions: - Is there any public repository that tells the flags used to compile the FFmpeg that is used by Qt? - Is FFmpeg the default backend for iOS? Thanks in advance, With my best regards, Nuno > On 16 Nov 2024, at 21:35, Nuno Santos <nuno.san...@imaginando.pt> wrote: > > Joger, > > I’ve misread the documentation. > > Passing /opt/homebrew/Cellar/ffmpeg/7.1/ fixes the problem. > > Now I will try to build Qt with FFmpeg and give it a try. > > Thanks! > > Nuno > >> On 16 Nov 2024, at 10:41, Nuno Santos <nuno.san...@imaginando.pt> wrote: >> >> Joger, >> >> I could only get back to this now. >> >> Trying to build Qt with FFmpeg. As a start point I’m point to prebuilt >> libraries by brew: >> >> ./configure -prefix /Users/nsantos/Qt/6.8.0/macos_static_vs -static >> -debug-and-release -- -DCMAKE_OSX_ARCHITECTURES="x86_64;arm64" >> -DFFMPEG_DIR=/opt/homebrew/Cellar/ffmpeg/7.1/lib >> >> Which has: >> >> -r--r--r-- 1 nsantos admin 10232192 9 Out 16:07 >> libavcodec.61.19.100.dylib >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libavcodec.61.dylib -> >> libavcodec.61.19.100.dylib >> -r--r--r-- 1 nsantos admin 14165144 30 Set 00:31 libavcodec.a >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libavcodec.dylib -> >> libavcodec.61.19.100.dylib >> -r--r--r-- 1 nsantos admin 206528 9 Out 16:07 >> libavdevice.61.3.100.dylib >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libavdevice.61.dylib -> >> libavdevice.61.3.100.dylib >> -r--r--r-- 1 nsantos admin 90232 30 Set 00:31 libavdevice.a >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libavdevice.dylib -> >> libavdevice.61.3.100.dylib >> -r--r--r-- 1 nsantos admin 3144864 9 Out 16:07 >> libavfilter.10.4.100.dylib >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libavfilter.10.dylib -> >> libavfilter.10.4.100.dylib >> -r--r--r-- 1 nsantos admin 5098240 30 Set 00:31 libavfilter.a >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libavfilter.dylib -> >> libavfilter.10.4.100.dylib >> -r--r--r-- 1 nsantos admin 2347712 9 Out 16:07 >> libavformat.61.7.100.dylib >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libavformat.61.dylib -> >> libavformat.61.7.100.dylib >> -r--r--r-- 1 nsantos admin 4220096 30 Set 00:31 libavformat.a >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libavformat.dylib -> >> libavformat.61.7.100.dylib >> -r--r--r-- 1 nsantos admin 643248 9 Out 16:07 >> libavutil.59.39.100.dylib >> lrwxr-xr-x 1 nsantos admin 25 30 Set 00:31 libavutil.59.dylib -> >> libavutil.59.39.100.dylib >> -r--r--r-- 1 nsantos admin 885096 30 Set 00:31 libavutil.a >> lrwxr-xr-x 1 nsantos admin 25 30 Set 00:31 libavutil.dylib -> >> libavutil.59.39.100.dylib >> -r--r--r-- 1 nsantos admin 85872 9 Out 16:07 >> libpostproc.58.3.100.dylib >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libpostproc.58.dylib -> >> libpostproc.58.3.100.dylib >> -r--r--r-- 1 nsantos admin 31880 30 Set 00:31 libpostproc.a >> lrwxr-xr-x 1 nsantos admin 26 30 Set 00:31 libpostproc.dylib -> >> libpostproc.58.3.100.dylib >> -r--r--r-- 1 nsantos admin 122096 9 Out 16:07 >> libswresample.5.3.100.dylib >> lrwxr-xr-x 1 nsantos admin 27 30 Set 00:31 libswresample.5.dylib >> -> libswresample.5.3.100.dylib >> -r--r--r-- 1 nsantos admin 115792 30 Set 00:31 libswresample.a >> lrwxr-xr-x 1 nsantos admin 27 30 Set 00:31 libswresample.dylib -> >> libswresample.5.3.100.dylib >> -r--r--r-- 1 nsantos admin 453536 9 Out 16:07 libswscale.8.3.100.dylib >> lrwxr-xr-x 1 nsantos admin 24 30 Set 00:31 libswscale.8.dylib -> >> libswscale.8.3.100.dylib >> -r--r--r-- 1 nsantos admin 547472 30 Set 00:31 libswscale.a >> lrwxr-xr-x 1 nsantos admin 24 30 Set 00:31 libswscale.dylib -> >> libswscale.8.3.100.dylib >> >> But the pre build summary says: >> >> src git:(v6.8.0) ✗ cat /Users/nsantos/Qt/6.8.0/src/config.summary | grep FF >> TIFF ................................... yes >> FFmpeg ............................... no >> FFmpeg plugin features: >> >> Any ideas on why it failed to include FFmpeg? >> >> How can I debug this? >> >> Thanks! >> >> Nuno >> >>> On 15 Oct 2024, at 12:31, Jøger Hansegård <joger.hanseg...@qt.io> wrote: >>> >>> Hi Nuno, >>> >>> I'm glad it helped. >>> >>> Yes, you can still link Qt Multimedia against a static build of FFmpeg. >>> When doing so, omit -DQT_DEPLOY_FFMPEG=ON when configuring Qt. >>> >>> You can find details about why we recommend using the FFmpeg media backend >>> at https://doc.qt.io/qt-6/qtmultimedia-index.html. In short, newer features >>> are only implemented with the FFmpeg media backend, and we will only fix >>> critical bugs on native backends. With critical bugs, we mean bugs that >>> affect security and reliability (crashes/hangs), not performance or >>> functionality bugs. We still welcome community contributions on the native >>> backends. The native Android backend is already deprecated and will be >>> removed with the next major Qt release. An example of a non-critical bug on >>> Windows with the native backend is that QMediaPlayer does not support >>> "zero-copy" transfer of textures from decoding to display. This can lead to >>> frame drop when playing high-resolution video. >>> >>> The FFmpeg media backend is, therefore, the most future-proof choice for >>> new projects. >>> >>> Thanks, >>> Jøger >>> >>> -----Original Message----- >>> From: Nuno Santos <nuno.san...@imaginando.pt> >>> Sent: Tuesday, October 15, 2024 12:31 PM >>> To: Jøger Hansegård <joger.hanseg...@qt.io> >>> Cc: interestqt-project. org <interest@qt-project.org> >>> Subject: Re: [Interest] Qt 6.8.0 - FFMPEG on Windows - Is it possible? >>> >>> Joger, >>> >>> Thanks for your reply. >>> >>> It seems that I have failed this little detail: >>> >>> -DQT_DEPLOY_FFMPEG=ON >>> >>> Also, is it possible to statically link ffmpeg to Qt? Or will we always >>> need to have the dlls somewhere? >>> >>> One thing that I still couldn't figure out is what are the main advantages >>> of using ffmpeg as backend compared with the native backends? >>> >>> Thank you! >>> >>> Best, >>> >>> Nuno >>> >>>> On 14 Oct 2024, at 17:42, Jøger Hansegård <joger.hanseg...@qt.io> wrote: >>>> >>>> There is also some information in the official Qt documentation; see: >>>> https://doc.qt.io/qt-6/qtmultimedia-building-from-source.html >>>> >>>> Best regards, >>>> Jøger Hansegård, >>>> The Qt Company >>>> >>>> >>>> -----Original Message----- >>>> From: Interest <interest-boun...@qt-project.org> On Behalf Of Jøger >>>> Hansegård via Interest >>>> Sent: Monday, October 14, 2024 6:21 PM >>>> To: Nuno Santos <nuno.san...@imaginando.pt>; interestqt-project. org >>>> <interest@qt-project.org> >>>> Subject: Re: [Interest] Qt 6.8.0 - FFMPEG on Windows - Is it possible? >>>> >>>> Hi Nuno, >>>> >>>> Yes, this is possible, and we are working on improving the documentation >>>> on how to do it. In the meantime, this is one way to do it: >>>> >>>> 1. Download FFmpeg built with shared libraries from one of the links below. >>>> 2. After unzipping the FFmpeg binaries to a suitable location, configure >>>> Qt: >>>> >>>> configure.bat <your normal settings> -- -DFFMPEG_DIR=<path to directory >>>> containing FFmpeg include/lib/bin folders> -DQT_DEPLOY_FFMPEG=ON >>>> >>>> Note the double '--' that separates configure arguments from CMake >>>> arguments. Once this is done, you can build Qt as usual. >>>> >>>> Be aware that he FFmpeg version in the link below is a GPL build. If this >>>> is not suitable for you, I added a link to my unofficial wiki page that >>>> describes different ways to build FFmpeg for Windows. This gives you >>>> control over building FFmpeg without any GPL or non-free components. Among >>>> the described options, using VCpkg is the simplest. >>>> >>>> Download links: >>>> FFmpeg for Windows (GPL): https://ffmpeg.org/download.html#build-windows >>>> (use the ones from BtbN, direct link: >>>> https://github.com/BtbN/FFmpeg-Builds/releases). It contains shared >>>> libraries and FFmpeg header files. >>>> Building FFmpeg: >>>> https://wiki.qt.io/User:Joger/Building_Qt_Multimedia_with_FFmpeg >>>> >>>> Thanks, >>>> Jøger >>>> The Qt Company >>>> >>>> -----Original Message----- >>>> From: Interest <interest-boun...@qt-project.org> On Behalf Of Nuno Santos >>>> via Interest >>>> Sent: Monday, October 14, 2024 5:04 PM >>>> To: interestqt-project. org <interest@qt-project.org> >>>> Subject: [Interest] Qt 6.8.0 - FFMPEG on Windows - Is it possible? >>>> >>>> Hi, >>>> >>>> I do I enable FFMPEG backend on Windows? >>>> >>>> Is it even possible? >>>> >>>>> configure.bat -help >>>> >>>> does not have any mention to it. >>>> >>>> Thanks! >>>> >>>> Regards, >>>> >>>> Nuno >>>> _______________________________________________ >>>> Interest mailing list >>>> Interest@qt-project.org >>>> https://lists.qt-project.org/listinfo/interest >>>> _______________________________________________ >>>> Interest mailing list >>>> Interest@qt-project.org >>>> https://lists.qt-project.org/listinfo/interest >>> >> > _______________________________________________ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
