How to obtain list of audio input Devices with ffmpeg

Saviz

I have some code that uses a QProcess object to call ffmpeg executable in the background to perform some tasks.

In this case I am trying to obtain the list of audio input device names from ffmpeg.

Code:

#include <QApplication>
#include <QDebug>
#include <QProcess>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QProcess process;
    QStringList arguments;
     
    arguments
              << "-hide_banner"
              << "-nostats"
              << "-list_devices"
              << "true"
              << "-f"
              << "dshow"
              << "-i"
              << "dummy";
    
    
    
        process.start("Path/to/ffmpeg", arguments);
    
        process.waitForFinished();
    
        // I use standard error because the "dummy" argument seems to raise a warning/error
        QByteArray output = process.readAllStandardError();
    
    
        qDebug() << output;
    
        process.close();

        return a.exec();
}

The code above works fine. (At least, it does exactly what it is told to...)

Here is the debug output:

[dshow @ 0000019e7d4190c0] "OBS Virtual Camera" (video)
[dshow @ 0000019e7d4190c0]   Alternative name "@device_sw_{860BB310-5D01-11D0-BD3B-00A0C911CE86}\{A3FCE0F5-3493-419F-958A-ABA1250EC20B}"
[dshow @ 0000019e7d4190c0] "Microphone (Realtek(R) Audio)" (audio)
[dshow @ 0000019e7d4190c0]   Alternative name "@device_cm_{33D9A762-90C8-11D0-BD43-00A0C911CE86}\wave_{2409F2C8-F2CB-4A6D-AEA7-DAD79C4EE9DF}"
dummy: Immediate exit requested

There are two questions that I have about this:

1- Currently, I use the readAllStandardError() method instead of the readAllStandardOutput() method, because the "dummy" argument in ffmpeg raises a Warning/Error. Is there a better alternative to this?

2- The output generated by the above command does indeed list the devices, but I only need the audio devices. Furthermore, I need the format to be more friendly. Something similar to the following:

"OBS Virtual Camera" (video)
"Microphone (Realtek(R) Audio)" (audio)
 Other audio devices...

So, I can retrieve them and put them in a QByteArray to show it in a GUI later on. Is there a better command to this that I am missing?

(I am using a windows 11 machine for ffmpeg)

Bonnie

@Saviz Hey dear, this is not a ffmpeg related forum. You should find one and ask there if you want help about ffmpeg command.

Ok, here's from what I know, there's no better command.
If you want friendly output, just parse the text to read the names and write what you want to the GUI.

*Note: The output of your audio devices contains both (video) and (audio) because that video device in the list can also be used as an audio input device. So I think we should keep that.

JonB

@Saviz
For the questions about what command line arguments you might want to pass to it you might be better asking in a forum for ffmpeg.

When running a command whose output you are interested in you should always read both standard output and standard error.

If you do not need to process them separately you might use QProcess::MergedChannels. But not if you need to parse them distinctly.

If you want the output you show, and ffmpeg does not offer this, parse the output to produce what you want.