Code sample - FM radio and TV tuning

Delphi and C# (ActiveX) sample code.

Get the 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 the 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 the 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 the 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 a 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;};

Once each channel is found, the event will be called and the channel will be added to the combo box. 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();

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