Code sample - FM Radio and TV Tuning

Delphi and C# (ActiveX) sample code.

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Get list of available TV Tuners 

for I := 0 to VideoCapture1.TVTuner_Devices_GetCount - 1 do
  cbTVTuner.Items.Add(VideoCapture1.TVTuner_Devices_GetItem(i));

for (int i = 0; i < VideoCapture1.TVTuner_Devices_GetCount(); i++)
  cbTVTuner.Items.Add(VideoCapture1.TVTuner_Devices_GetItem(i));

Get list of available TV formats 

for I := 0 to VideoCapture1.TVTuner_TVFormats_GetCount - 1 do
  cbTVSystem.Items.Add(VideoCapture1.TVTuner_TVFormats_GetItem(i));

for (int i = 0; i < VideoCapture1.TVTuner_TVFormats_GetCount(); i++)
  cbTVSystem.Items.Add(VideoCapture1.TVTuner_TVFormats_GetItem(i));

Get list of countries 

for I := 0 to VideoCapture1.TVTuner_Countries_GetCount - 1 do
  cbTVCountry.Items.Add(VideoCapture1.TVTuner_Countries_GetItem(i));

for (int i = 0; i < VideoCapture1.TVTuner_Countries_GetCount(); i++)
  cbTVCountry.Items.Add(VideoCapture1.TVTuner_Countries_GetItem(i));

Select TV Tuner 

VideoCapture1.TVTuner_Name := cbTVTuner.Items[cbTVTuner.ItemIndex];

VideoCapture1.TVTuner_Name = cbTVTuner.Text;

Read TV Tuner settings 

VideoCapture1.TVTuner_Read;

VideoCapture1.TVTuner_Read();

Get list of available TV modes 

for I := 0 to VideoCapture1.TVTuner_Modes_GetCount - 1 do
  cbTVMode.Items.Add(VideoCapture1.TVTuner_Modes_GetItem(i));

for (int i = 0; i < VideoCapture1.TVTuner_Modes_GetCount(); i++)
  cbTVMode.Items.Add(VideoCapture1.TVTuner_Modes_GetItem(i));

Get current audio and video frequencies. 

edVideoFreq.Text := IntToStr(VideoCapture1.TVTuner_VideoFrequency);
edAudiofreq.Text := IntToStr(VideoCapture1.TVTuner_AudioFrequency);

edVideoFreq.Text = Convert.ToString(VideoCapture1.TVTuner_VideoFrequency);
edAudioFreq.Text = Convert.ToString(VideoCapture1.TVTuner_AudioFrequency);

Select signal source 

cbTVInput.ItemIndex := cbTVInput.Items.IndexOf(VideoCapture1.TVTuner_InputType);

cbTVInput.SelectedIndex = cbTVInput.Items.IndexOf(VideoCapture1.TVTuner_InputType);

Select work mode 

cbTVMode.ItemIndex := cbTVMode.Items.IndexOf(VideoCapture1.TVTuner_Mode);

cbTVMode.SelectedIndex = cbTVMode.Items.IndexOf(VideoCapture1.TVTuner_Mode);

Select TV system (PAL, NTSC, SECAM, etc.) 

cbTVSystem.ItemIndex := cbTVSystem.Items.IndexOf(VideoCapture1.TVTuner_TVFormat);

cbTVSystem.SelectedIndex = cbTVSystem.Items.IndexOf(VideoCapture1.TVTuner_TVFormat);

Select country 

cbTVCountry.ItemIndex := cbTVCountry.Items.IndexOf(VideoCapture1.TVTuner_Country);

cbTVCountry.SelectedIndex = cbTVCountry.Items.IndexOf(VideoCapture1.TVTuner_Country);

Write TVTuner_TuneChannels event code. 

procedure TForm1.VideoCapture1TVTunerTuneChannels(SignalPresent: Boolean; Channel, Frequency, Progress: Integer);
begin
  pbChannels.Position := Progress;

  if SignalPresent then
    cbTVChannel.Items.Add(IntToStr(Channel));

  if Channel = -1 then
    begin
      pbChannels.Position := 0;
      ShowMessage('AutoTune complete');
    end;
end;

private void VideoCapture1_OnTVTunerTuneChannels(
	object sender, 
	AxVisioForge_Video_Capture_3.IVFVideoCaptureXEvents_OnTVTunerTuneChannelsEvent e)
{
  pbChannels.Value = e.progress;

  if (e.signalPresent)
    cbTVChannel.Items.Add(e.channel.ToString());

  if (e.channel == -1)
  {
    pbChannels.Value = 0;
    MessageBox.Show("AutoTune complete");
  };
}

Start tune process 

const KHz = 1000;
const MHz = 1000000;

VideoCapture1.TVTuner_Read;
cbTVChannel.Items.Clear;

//If you select FM Tuning, you can specify the initial frequencies and the scanning pitch

if ( (cbTVMode.ItemIndex <> -1) and (cbTVMode.Items[cbTVMode.ItemIndex] = 'FM Radio') ) then
  begin
    VideoCapture1.TVTuner_FM_Tuning_StartFrequency := 100 * Mhz;
    VideoCapture1.TVTuner_FM_Tuning_StopFrequency := 110 * MHz;
    VideoCapture1.TVTuner_FM_Tuning_Step := 100 * KHz;
  end;

VideoCapture1.TVTuner_TuneChannels_Start;

const int KHz = 1000;
const int MHz = 1000000;

VideoCapture1.TVTuner_Read();
cbTVChannel.Items.Clear();

//If you select FM Tuning, you can specify the initial frequencies and the scanning pitch

if ( (cbTVMode.SelectedIndex != -1) && (cbTVMode.Text == "FM Radio") )
{
  VideoCapture1.TVTuner_FM_Tuning_StartFrequency = 100 * MHz;
  VideoCapture1.TVTuner_FM_Tuning_StopFrequency = 110 * MHz;
  VideoCapture1.TVTuner_FM_Tuning_Step = 100 * KHz;};

VideoCapture1.TVTuner_TuneChannels_Start();

Once each channel is found, the event will be called and the channel will be added to the combobox. Also, you can specify the frequency and number of each channel manually. 

Set channels by number 

VideoCapture1.TVTuner_Channel := StrToInt(edChannel.Text);
VideoCapture1.TVTuner_Apply;

VideoCapture1.TVTuner_Channel = Convert.ToInt32(edChannel.Text);
VideoCapture1.TVTuner_Apply();

Set radio frequency 

VideoCapture1.TVTuner_Channel := -1; // must be -1 to use frequency
VideoCapture1.TVTuner_Frequency := StrToInt(edChannel.Text);
VideoCapture1.TVTuner_Apply;

VideoCapture1.TVTuner_Channel = -1; // must be -1 to use frequency
VideoCapture1.TVTuner_Frequency = Convert.ToInt32(edChannel.Text);
VideoCapture1.TVTuner_Apply();