_audio_stream->Connect (wxID_ANY, wxEVT_COMMAND_CHOICE_SELECTED, wxCommandEventHandler (FFmpegContentDialog::audio_stream_changed), 0, this);
_subtitle_stream->Connect (wxID_ANY, wxEVT_COMMAND_CHOICE_SELECTED, wxCommandEventHandler (FFmpegContentDialog::subtitle_stream_changed), 0, this);
_audio_stream->Connect (wxID_ANY, wxEVT_COMMAND_CHOICE_SELECTED, wxCommandEventHandler (FFmpegContentDialog::audio_stream_changed), 0, this);
_subtitle_stream->Connect (wxID_ANY, wxEVT_COMMAND_CHOICE_SELECTED, wxCommandEventHandler (FFmpegContentDialog::subtitle_stream_changed), 0, this);