#1237 Ensure MP3 input sample rate is supported by LAME encoder settings. (#1376)

Co-authored-by: Dennis Sheirer <dsheirer@github.com>

src/main/java/io/github/dsheirer/audio/convert/InputAudioFormat.java

@@ -20,6 +20,7 @@
 package io.github.dsheirer.audio.convert;
 
 import io.github.dsheirer.audio.AudioFormats;
+import java.util.EnumSet;
 
 import javax.sound.sampled.AudioFormat;
 
@@ -29,8 +30,8 @@ import javax.sound.sampled.AudioFormat;
 public enum InputAudioFormat
 {
     SR_8000(AudioFormats.PCM_SIGNED_8000_HZ_16_BIT_MONO, "16-Bit 8000 Hz (no resample)"),
-    SR_16000(AudioFormats.PCM_SIGNED_16000_HZ_16_BIT_MONO, "16-Bit 16000 Hz"),
+    SR_16000(AudioFormats.PCM_SIGNED_16000_HZ_16_BIT_MONO, "16-Bit 16000 Hz (default)"),
-    SR_22050(AudioFormats.PCM_SIGNED_22050_HZ_16_BIT_MONO, "16-Bit 22050 Hz (default)"),
+    SR_22050(AudioFormats.PCM_SIGNED_22050_HZ_16_BIT_MONO, "16-Bit 22050 Hz"),
     SR_44100(AudioFormats.PCM_SIGNED_44100_HZ_16_BIT_MONO, "16-Bit 44100 Hz"),
 
     SR_32_8000(AudioFormats.PCM_SIGNED_8000_HZ_32_BIT_MONO, "32-Bit 8000 Hz (no resample)"),
@@ -41,6 +42,17 @@ public enum InputAudioFormat
     private AudioFormat mAudioFormat;
     private String mLabel;
 
+    /**
+     * Set that includes sample rates of 8 or 16 kHz
+     */
+    public static final EnumSet<InputAudioFormat> SAMPLE_RATES_8_16 = EnumSet.of(SR_8000, SR_32_8000, SR_16000, SR_32_16000);
+
+    /**
+     * Set that includes sample rates of 8, 16, or 22 kHz
+     */
+    public static final EnumSet<InputAudioFormat> SAMPLE_RATES_8_16_22 = EnumSet.of(SR_8000, SR_32_8000, SR_16000,
+            SR_32_16000, SR_22050, SR_32_22050);
+
     /**
      * Constructs an instance
      * @param audioFormat for the specified sample rate
@@ -56,7 +68,7 @@ public enum InputAudioFormat
      */
     public static InputAudioFormat getDefault()
     {
-        return SR_22050;
+        return SR_16000;
     }
 
     /**

src/main/java/io/github/dsheirer/audio/convert/MP3AudioConverter.java

@@ -60,8 +60,17 @@ public class MP3AudioConverter implements IAudioConverter
         mEncoder = LameFactory.getLameEncoder(inputAudioFormat, setting);
         mNormalizeAudio = normalizeAudio;
 
+        //Ensure input audio sample rate is supported for the MP3 setting and update as necessary - should never happen.
+        if((mInputAudioFormat.getSampleRate() - mEncoder.getEffectiveSampleRate()) > 1.0)
+        {
+            mInputAudioFormat = InputAudioFormat.getDefault();
+            mLog.warn("MP3 setting [" + setting + "] does not support requested input audio sample rate [" +
+                    inputAudioFormat + "] - using default sample rate [" + mInputAudioFormat + "]");
+            mEncoder = LameFactory.getLameEncoder(inputAudioFormat, setting);
+        }
+
         //Resampling is only required if desired input sample rate is not system default of 8kHz
-        if(inputAudioFormat != InputAudioFormat.SR_8000 && inputAudioFormat != InputAudioFormat.SR_32_8000)
+        if(mInputAudioFormat != InputAudioFormat.SR_8000 && mInputAudioFormat != InputAudioFormat.SR_32_8000)
         {
             mResampler = LameFactory.getResampler(inputAudioFormat);
         }

src/main/java/io/github/dsheirer/audio/convert/MP3Setting.java

@@ -19,6 +19,8 @@
 
 package io.github.dsheirer.audio.convert;
 
+import java.util.Arrays;
+import java.util.List;
 import net.sourceforge.lame.mp3.Lame;
 
 /**
@@ -79,6 +81,30 @@ public enum MP3Setting
         return mSetting;
     }
 
+    /**
+     * Input audio formats that are supported by the MP3Setting value.
+     * @return list of supported input audio sample rates.
+     */
+    public List<InputAudioFormat> getSupportedSampleRates()
+    {
+        switch(this)
+        {
+            case CBR_16:
+            {
+                return InputAudioFormat.SAMPLE_RATES_8_16.stream().toList();
+            }
+            case CBR_32:
+            case VBR_7:
+            {
+                return InputAudioFormat.SAMPLE_RATES_8_16_22.stream().toList();
+            }
+            default:
+            {
+                return Arrays.stream(InputAudioFormat.values()).toList();
+            }
+        }
+    }
+
     @Override
     public String toString()
     {

src/main/java/io/github/dsheirer/gui/preference/mp3/MP3PreferenceEditor.java

@@ -25,6 +25,7 @@ import io.github.dsheirer.preference.UserPreferences;
 import io.github.dsheirer.preference.mp3.MP3Preference;
 import javafx.geometry.HPos;
 import javafx.geometry.Insets;
+import javafx.scene.control.Alert;
 import javafx.scene.control.CheckBox;
 import javafx.scene.control.ComboBox;
 import javafx.scene.control.Label;
@@ -99,12 +100,47 @@ public class MP3PreferenceEditor extends HBox
             mMP3SettingComboBox.getItems().addAll(MP3Setting.values());
             mMP3SettingComboBox.getSelectionModel().select(mMP3Preference.getMP3Setting());
             mMP3SettingComboBox.getSelectionModel().selectedItemProperty()
-                    .addListener((observable, oldValue, newValue) -> mMP3Preference.setMP3Setting(newValue));
+                    .addListener((observable, oldValue, newValue) -> {
+                        mMP3Preference.setMP3Setting(newValue);
+                        updateAudioSampleRateComboBox();
+                    });
         }
 
         return mMP3SettingComboBox;
     }
 
+    /**
+     * Updates the input sample rate combo box values and alerts the user whenever we auto-change an input sample rate
+     * due to a change in the MP3 setting value.
+     */
+    private void updateAudioSampleRateComboBox()
+    {
+        InputAudioFormat currentSelection = getAudioSampleRateComboBox().getSelectionModel().getSelectedItem();
+        MP3Setting setting = getMP3SettingComboBox().getSelectionModel().getSelectedItem();
+
+        getAudioSampleRateComboBox().getItems().clear();
+        getAudioSampleRateComboBox().getItems().addAll(setting.getSupportedSampleRates());
+
+        if(currentSelection != null && getAudioSampleRateComboBox().getItems().contains(currentSelection))
+        {
+            getAudioSampleRateComboBox().getSelectionModel().select(currentSelection);
+        }
+        else
+        {
+            getAudioSampleRateComboBox().getSelectionModel().select(InputAudioFormat.getDefault());
+
+            Alert alert = new Alert(Alert.AlertType.INFORMATION);
+            alert.setTitle("Sample Rate Updated");
+            alert.setHeaderText("Input Sample Rate Updated");
+
+            Label wrappingLabel = new Label("Previous input sample rate [" + currentSelection +
+                    "] is not supported with encoder setting [" + setting + "].  Sample rate updated to default.");
+            wrappingLabel.setWrapText(true);
+            alert.getDialogPane().setContent(wrappingLabel);
+            alert.show();
+        }
+    }
+
     private ComboBox<InputAudioFormat> getAudioSampleRateComboBox()
     {
         if(mAudioSampleRateComboBox == null)
@@ -113,7 +149,12 @@ public class MP3PreferenceEditor extends HBox
             mAudioSampleRateComboBox.getItems().addAll(InputAudioFormat.values());
             mAudioSampleRateComboBox.getSelectionModel().select(mMP3Preference.getAudioSampleRate());
             mAudioSampleRateComboBox.getSelectionModel().selectedItemProperty()
-                    .addListener((observable, oldValue, newValue) -> mMP3Preference.setAudioSampleRate(newValue));
+                    .addListener((observable, oldValue, newValue) -> {
+                        if(newValue != null)
+                        {
+                            mMP3Preference.setAudioSampleRate(newValue);
+                        }
+                    });
         }
 
         return mAudioSampleRateComboBox;

src/main/java/io/github/dsheirer/preference/mp3/MP3Preference.java

@@ -116,6 +116,24 @@ public class MP3Preference extends Preference
             {
                 mInputAudioFormat = InputAudioFormat.getDefault();
             }
+
+            //Ensure the input sample rate is supported by the MP3 setting, or change it to the first supported rate.
+            MP3Setting setting = getMP3Setting();
+
+            if(!setting.getSupportedSampleRates().contains(mInputAudioFormat))
+            {
+                InputAudioFormat supportedAudioFormat = InputAudioFormat.getDefault();
+
+                //Default should always be supported by all mp3 settings, but fall-back to a supported rate if not.
+                if(!setting.getSupportedSampleRates().contains(supportedAudioFormat))
+                {
+                    supportedAudioFormat = setting.getSupportedSampleRates().get(0);
+                }
+
+                mLog.warn("MP3 Setting [" + setting + "] does not support input sample rate [" + getAudioSampleRate().name() +
+                        "] - updating to supported sample rate [" + supportedAudioFormat.name() + "]");
+                setAudioSampleRate(supportedAudioFormat);
+            }
         }
 
         return mInputAudioFormat;