QMediaPlayer “Failed to load media” on iOS

canellas

Hi!

My application is written using QWidget, no QtQuick, and on iOS 'QMediaPlayer::supportedAudioCodecs()' returns '("audio/pcm")' and 'QMediaPlayer::supportedContainers()' returns ' ("audio/x-wav", "audio/x-raw")'.

An audio file was recorded at 'QUrl("file:///Users/canellas/Library/Application Support/iPhone Simulator/2.2/Documents/Desktop/28_94_1.wav")', but when I try to play it, QMediaPlayer signals 'error', and the slot I wrote prints the error parameter as 'QMediaPlayer::FormatError', and 'QMediaPlayer::errorString()' prints "Failed to load media".

The same code works fine on Android and OSX.

Could the space in 'Application Support' or in 'iPhone Simulator' cause this error? I wonder because the path on OSX or on Android has no spaces. I tried to create a QUrl object using HTML codes for spaces, but, AKAIK, QUrl does not allow it.

Thanks!

SGaist

Hi,

Might be more related to the fact that you are using a simulator. Can you check that again on a real device ?

canellas

@SGaist

Unfortunately, not right now... only next Monday... I'll try again, and let you know.

Thanks!

canellas

Well, I tried again using a real iPhone, but it did not work.

I would appreciate very much any other idea...

Thanks!

canellas

More and more it seems to have something to do with the path. Running on the iOS simulator, I was able to change the path to "file:///Users/canellas/", and the audio file was recorded and played back normally.

I'll try to change the path in the iPhone, and compare the results.

SGaist

Try creating your URL with QUrl::fromLocalFile

canellas

SGaist,

I really appreciate your help. Thanks a lot!

I wrote a slot for 'error' signal from QAudioRecorder, which is actually inherited from QMediaRecorder, and it revealed the 'QMediaRecorder::ResourceError'.

That happens in the simulator as well as on the iPhone.

I am searching the web, but no luck so far.

Any ideas?

Thanks!

SGaist

Did you change the QUrl creation part like suggested ?

canellas

Sorry, I forgot to report that I've changed the QUrl construction, as you suggested, but with no different results

SGaist

Did you check that it's valid just in case ?

canellas

Yes, it was a valid path.

SGaist

I meant: did you validate that with QUrl ? With isValid and isLocalFile ?

canellas

I believe it is.

The following code

void Gravar::h6() {

    qDebug() << "h6 >>>";

    try {
        set_current(playing);

        qDebug() << "m_audio_recorder->outputLocation() = " << m_audio_recorder->outputLocation();

        QString _path = m_audio_recorder->outputLocation().path();
        qDebug() << "_path = " << _path;

        QUrl _url (QUrl::fromLocalFile(_path));
        qDebug() << "url = " << _url;

        if  (!_url.isValid()) {
            qDebug() << "INVALID URL!";
            return;
        }

        qDebug() << "valid url";

        if (!_url.isLocalFile()) {
            qDebug() << "NOT A LOCAL FILE!";
            return;
        }

        qDebug() << "local file";

        QMediaContent _content(_url);
        qDebug() << "h6-content '" << _content.canonicalUrl() << "'\n";

        m_player->setMedia(_content);
        m_player->setVolume(100);
        m_player->play();
    }
    catch (std::exception & _ex) {
        qDebug() << "FATAL: '" << _ex.what() << "'\n";
        state_transition(reset);
    }

    qDebug() << "h6 <<<";
}

prints this output:

h6 >>>
m_audio_recorder->outputLocation() =  QUrl("file:///var/mobile/Containers/Data/Application/CBAAF069-4B9B-4521-9BB2-0754DBA3E24F/Documents/Music/28_94_1.wav")
_path =  "/var/mobile/Containers/Data/Application/CBAAF069-4B9B-4521-9BB2-0754DBA3E24F/Documents/Music/28_94_1.wav"
url =  QUrl("file:///var/mobile/Containers/Data/Application/CBAAF069-4B9B-4521-9BB2-0754DBA3E24F/Documents/Music/28_94_1.wav")
valid url
local file
h6-content ' QUrl("file:///var/mobile/Containers/Data/Application/CBAAF069-4B9B-4521-9BB2-0754DBA3E24F/Documents/Music/28_94_1.wav") '

h6 <<<

I think it is very important to notice that when I call 'm_audio_recorder->record()', a slot I wrote for 'error' signal from QAudioRecorder prints 'Recording error: QMediaRecorder::ResourceError', and from there on, no signal is emitted anymore.

Again, thanks a lot for your help.

NickV

You can try this in the .pro file:

QTPLUGIN += qtaudio_coreaudio

canellas

I've already tried that, and I can do it again, but only tomorrow, because today I am trying to solve the problem of pausing the voice recording in Android.

I'll let you know the results.

Thanks!

canellas

I found what is causing the error!

Running the app on a iPhone 5 real device, when I print the standard paths, I get:

DesktopLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Documents/Desktop"
DocumentsLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Documents"
ApplicationsLocation = ""
MusicLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Documents/Music"
MoviesLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Documents/Movies"
PicturesLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Documents/Pictures"
TempLocation = "/private/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/tmp"
HomeLocation = "/private/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738"
DataLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Application Support/perinatal__app__app_mae"
CacheLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Caches/perinatal__app__app_mae"
GenericDataLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Application Support"
RuntimeLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Application Support"
ConfigLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Preferences"
GenericConfigLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Preferences"
DownloadLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Documents/Downloads"
GenericCacheLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Caches"
AppDataLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Application Support/perinatal__app__app_mae"
AppLocalDataLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Application Support/perinatal__app__app_mae"
AppConfigLocation = "/var/mobile/Containers/Data/Application/D424B7BE-6230-4868-8B85-09324C845738/Library/Preferences/perinatal__app__app_mae"

The first problem is that the all the paths starting with '/var/' are wrong, the actual path is '/private/var'. So, when I try to use 'MusicLocation', in the slot for the 'error' signal, 'QAudioRecorder::errorString' prints "Can't open output location". I can not prefix 'MusicLocation' with '/private' because this location changes between versions of iPhone.

Running the 'Examples/multimedia/audiorecorder' example, it is possible to navigate in the file system of the iPhone 5, and one can see that the '/var' directory is actually a link, but when you enter the directory, although one could expect to see the 'mobile' sub directory, there is nothing there.

The documentation for 'QStandardPaths::writableLocation(StandardLocation type)' says "Note: The storage location returned can be a directory that does not exist; i.e., it may need to be created by the system or the user.", but I can not create any directory below '/var', where ever it really is.

In the iPhone 6 simulator, the 'MusicLocation' is "/Users/canellas/Library/Application Support/iPhone Simulator/2.2/Documents/Music", wich does not exist, but I could create it. I do not know if I would be able to create it, if it was a real iPhone device.

I could not create the audio file at 'HomeLocation'. The only path that worked was 'TempLocation', on the iPhone 5 cell, and on the iPhone 6 simulator.

Does anyone know how correctly use 'QStandardPaths'? Or am I using it right, and there is a bug there?

Thanks a lot for reading all this! 8)

SGaist

Which version of iOS are you running ?

canellas

On the iPhone 5 it is 9.3.3 (13G34). On the iPhone 6s simulator it is 9.3 (13E30).

Thanks!

GBergamo

Any update on this?