A project of mine is written with Qt5/c++, using the QMediaPlayer class to read audio files. Everything's ok as long as I run this project on Linux.
Since I want to run my program on Windows, I use MXE to compile my code and create a binary file for Windows systems.
The program seems ok, except this problem with the QMediaPlayer class. When the program runs on a Windows system, I read this message :
defaultServiceProvider::requestService(): no service found for - "org.qt-project.qt.mediaplayer".
By googling around, I came to understand that the QMediaPlayer used several plugins, different on each platform. On Windows, The WMF plugin is Microsoft-only, DirectShow seems useless; others suggest to use other external plugins like portaudio, SdlAudio ou OpenAI.
How may I solve this problem ?
I found the problem and know how to fix it : according to this thread, just add the following line to your .pro file :
QTPLUGIN += dsengine qtmedia_audioengine
Related
I downloaded C++ code from GitHub to tag images for training an object detector using Machine Learning.
Within Qt Creator 4.2.1 Based on Qt 5.8.0 (MSVC 2015, 32bit), I was able to compile and run the code. Unfortunately, I was not able to run the .exe outside of Qt Creator.
Initially, I received an error that
"The program can't start because libgcc_s_dw2-1.dll is missing".
Thanks to
QT The program can't start because libgcc_s_dw2-1.dll is missing, that was fixed easily by adding
"QMAKE_LFLAGS += -static"
to the .pro file. Now, when I run it I get
"The application was unable to start correctly (0xc000007b). Click OK to close the application."
I was able to reproduce the error using the simple "Hello World" default project that appears when you create a Qt Widget Application. This led me to believe something was wrong with my installation.
Based on the advice of this article: https://stackoverflow.com/questions/12099117/32-bit-qt-application-on-win-7-x64-wont-run-but-runs-fine-from-qt-creator, I used Dependency Walker to identify possible causes. I expected to see only a few items that I can follow up on. Instead, I received a list of close to 100 missing .dll files. All the files started with
"API-MS-WIN ###.DLL" or "EXT-MS ###.DLL"
where ### represent some additional text characters, for example;
"API-MS-WIN-SHCORE-STREAM-WINRT-L1-1-0.DLL"
I'm attaching a sample output.
Another suggestion was to copy over
libwinpthread-1.dll, libstdc++-6.dll, libgcc_s_dw2-1.dll.
That did not work either.
My next move was to simply get the latest version of QT and wish for the best. I installed Qt Creator 4.8.1 Based on At 5.12.0 (MSVC 2015, 32 bit). This time, I could not even get the code to run in the IDE. I received 1000+ error messages!
Based on advice from several pages, I added
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
to the .pro file and it still would not compile.
Also, I verified that the application is being built as a 32bit application. I'm running on a 64 bit Windows 10 system.
If anyone would like to take a crack at it to see if they can create a working .exe, here is the link: github.com/clavicule/BBTag
Qt provides a tool to copy the necessary dlls to the folder of your executable.
The tools is called windeployqt.exe and comes with your Qt installation. For me it is located at C:\Qt\5.9.1\msvc2015_64\bin\windeployqt.exe. You will have to look at your installation path and probably the msvc_32 folder to find it.
Then you go to the folder with your executable in it, oben a command prompt or powershell and execute path\to\windeployqt.exe yourProgram.exe and it will automatically copy the necessary dll files to this folder. Afterwards you can run your program without issues.
The official documentation for the tool can be found here.
Alternative 1: While developing you could use QtCreator which automatically adds the paths to the dlls when running your program - make sure to include them if you deploy your program!
Alternative 2: Add the path to the necessary dlls to your PATH variable. This isn't recommended either, since everyone who gets your program would have to do the same to run it.
I figured it out! My installation of Anaconda (a Python distribution popular for data science and machine learning) is the culprit.
From: #remy-lebeau
The application was unable to start correctly (0xc000007b)
The error:
"The application was unable to start correctly (0xc000007b) ..."
is a good indicator that the 32-bit app tried to load a 64-bit DLL. At first, this did not make sense since I verified many times that I was using the 32 bit version of Qt.
It turns out that the installation of the 64 bit version of Anaconda also contained many Qt5 dlls used for the PyQt5 package. Since the path to this folder came before the path to my c:\Qt...\bin folder, it was used in the build instead of the actual 32 bit version installed with Qt. This was not obvious because I was unaware of PyQt5 so I had no idea that it came with Anaconda. A simple reordering of the path entries using the System Environment Variables interface AND a system restart fixed the problem.
Silver lining: I now know C++ and designing GUIs w/ QT and PyQt5
Thanks #albertmand and #jwernerny
I'm using Visual Studio 2015 Community to make a Qt-based GUI in C++ which includes a microphone input. I'm testing the microphone part, and am looping through QAudioDeviceInfo::AvailableDevices(QAudio::Mode::AudioInput) (and AudioOutput for that matter) and nothing is coming up. I've checked that my project includes QtMultimedia, and I definitely have audio devices on this computer. I'm stuck with an existing compiled Qt (since this application is plugging into another project), but I've verified that the Qt install has the QtMultimedia and the Windows audio plugins. The Qt version is 5.9.3.
The only thing I can think of is that the project isn't including the right plugin, but I don't know how to change that.
The issue was that I needed to run "windeployqt" on the built executable to get all of the plugins into the right place. I'm curious why it didn't work without that, but that's a VS + Qt plugin problem, not a Qt problem.
I'm trying to port code written in Qt on Windows to Qt on Ubuntu. The problem I'm facing is that it gives me this error for my ui_windowform.h header:
error: QtWidgets/QApplication: No such file or directory
I searched on Google for solutions but didn't find anything relevant. I've also added INCLUDEPATH += $QTDIR/include/qt4/QtGuito .pro file.
I mostly of agree with LukasT, but Qt 4 does still have QApplication, however it is located in a slightly different location :) .... or maybe :(
You should find it here: .../qt4/QtGui/QApplication .... or somthing like that, I can't quite recall now...
But I would definatley try to keep your Qt version the same on each platform then you garantee that you will have no Qt lib issues... compiler on the other hand is not garanteed :o (but I would not worry too much about that)
It looks like the original Qt code uses Qt5, QtWidgets/QApplication rings the bell from me [1] and you are pointing to Qt4 in Ubuntu. You should try to install Qt5 in Ubuntu.
[1] http://qt-project.org/doc/qt-5.0/qtwidgets/qtwidgets-index.html
I have some code compiled using Visual Studio 2010 (C++), with Qt for the GUI and Phonon to show some videos.
I compile and run the code in a Windows XP machine and everything works fine. The videos and controls are shown correctly, and the same in other Windows XP machines. But at the moment that I try to use a Windows 7 machine, the video is not shown. Phonon controls are loaded, I can adjust the size of the Phonon VideoWidget but nothing is shown. I am using the SetFile method to indicate the file location and I have also tried (of course, with no luck) with setCurrentSource in the MediaObject (it works, though, in Windows XP).
I have tried different locations of files (absolute/relative) but nothing seems to work. Also, in XP when a video is not found an alert message is shown while in Windows 7 there is no error message, but also no video is shown. If I try to open the videos with other players, they work fine (I tried also with videos with different formats).
Any idea on what can be wrong? Is there something that I am missing with Phonon and Windows 7? Thanks!
When deploying your application to a different computer, make sure you don't forget to copy the Phonon backend. Not just the DLL contained in it (the ds backend for me), but also the directory itself.
That is
-Application Directory
¦-myexe.exe
¦-phonon_backend
¦-phonon_ds94.dll
Furthermore the Phonon backend on Windows (and Mac I think) makes use of the QtOpenGL module. So don't forget to copy this either. It can go inside the application directory.
In any case you could help yourself out a bit by adding a small bit of code that shows (perhaps writes to a file) which mimetypes are available. If it doesn't spit out anything, there is a problem with your backend. (Well, that of your application...)
This is what I had to do when I used Phonon to play video inside my application. Since I only quickly added this some time ago to my application, I'm not 100% sure that this is the only (or even the proper) way to do this, so anyone who has different insights feel free to comment on this.
This is my first question after leeching over here for some time.. So spare me.
I need to apply the iZotope Vinyl VST effect to some audio files via CLI or C++ (so language doesn't really matter), it has to work on a Mac or on a Unix based system. I've researched all over the webs and can't find any working solution.
I've tried using MissWatson, a command line utility, this works but my result audio files are silent...
./MissWatson -plugin=Vinyl -input-file="/Users/Sjaq/Desktop/test.wav" -output-file="/Users/Sjaq/Downloads/MissWatson-v1.0-mac/res.wav" -parameter=1:0.6,2:0.6,11:0.4
Then I tried using the Steinberg VST SDK by creating a host application, starting from the vstvalidator provided by the SDK. But when I try to load the VST I get this error:
2010-12-01 16:57:40.774 vstvalidator[4654:903] Error loading /Library/Audio/Plug-Ins/VST/Vinyl.vst/Contents/MacOS/Vinyl: dlopen(/Library/Audio/Plug-Ins/VST/Vinyl.vst/Contents/MacOS/Vinyl, 262): no suitable image found. Did find:
/Library/Audio/Plug-Ins/VST/Vinyl.vst/Contents/MacOS/Vinyl: no matching architecture in universal wrapper
And I don't know what to do. I'm pretty new to C++ and and made a few apps without any issues, but this time I've hit a dead end.
I've read about pyvst but it seems to need a DLL for the VST so that didn't work either.
I'm the author of MissWatson, and as you probably noticed on the webpage, I unfortunately was required to close-source the code, so I can't really ask you for more diagnostic information, since I wouldn't be able to patch MissWatson if it's a bug there. However, I would recommend running MissWatson with the -verbose switch and perhaps logging that output to file if that floods your terminal. You might find something in that output which helps you to diagnose the problem.
Anyways, as for the error in your VST host, I have a feeling that you are compiling your app as a 64-bit executable and trying to load a 32-bit plugin. Since hardly any VST/AU plugins (and also sequencers, for that matter) have made the leap to 64-bit, you'd be better off just compiling your app as a 32-bit x86 binary.
By default, the "debug" configuration in Xcode only builds your app for the native architecture of your machine to save time during compilation. I would advise that you disable this feature in your project's build settings and always build with the architectures you plan to ship with. This will prevent weird cross-architecture types of errors like the one you saw above.
Edit: I have since started a new command-line VST host to replace MissWatson which is called MrsWatson. You should try using this tool instead.
Perhaps you can port the source code of this open source vst host to match your platforms?
http://www.hermannseib.com/english/vsthost.htm
Scroll down to the bottom of the page.
Hope it helps.