Converting audio/video tracks to AAC format in C# app.

[Alex1347]

I try convert audio/video tracks to AAC format using qaac lib. In CMD it works and output information about progress of convertation. In my C# app it works too, but I can't get information about progress, i try use these events: OutputDataReceived, ErrorDataReceived. In handler of ErrorDataReceived I don't get needed information, in handler of OutputDataReceived I get received.Data like null value. How can I get conversion progress information during conversion in C# code?

(I use qaac lib because ffmpeg lib convert tracks to AAC incorrect - incorrect duration of result track, resolving not find for this problem, some analog apps have the same bug.)

string arguments = $"\"{engineParameters.InputFile.Filename}\" -no-delay -o \"{engineParameters.OutputFile.Filename}\"";

processStartInfo = new ProcessStartInfo
{
    FileName = QaacFilePath,
    Arguments = arguments,
    RedirectStandardOutput = true,
    UseShellExecute = false,
    CreateNoWindow = true,
    WindowStyle = ProcessWindowStyle.Hidden
};

Also i call these methods for process:

BeginOutputReadLine();
BeginErrorReadLine();
WaitForExit();

Handlers:

this.Process.OutputDataReceived += (sender, received) =>
{
    if (received.Data == null) return;
    //Some code...
}

this.Process.ErrorDataReceived += (sender, received) =>
{
    if (received.Data == null) return;
    //Some code...
}

 

[Skydiver]

If "qaac lib" is truly a library, why don't you just PInvoke the APIs of the library directly? I have a feeling based on a quick scan of the documentation links that "qaac" is actually a "prog" or "cli" and not a "lib".

 

[Skydiver]

Yup, looking at the source code, it definitely is a command line application, and not a library.

Anyway, part of the reason you are not getting any progress output is because the PeriodicDisplay class checks to see if the console window is visible. Since you are launching the app to be in a hidden window, then the progress is not displayed.

qaac/main.cpp at master · nu774/qaac

CLI QuickTime AAC/ALAC encoder. Contribute to nu774/qaac development by creating an account on GitHub.

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