remove mel/hz calculation for separate fix

src/lenses/SpectrogramLens/Spectrogram.tsx

@@ -51,40 +51,4 @@ const amplitudeToDb = (amplitude: number, ref: number, amin: number) => {
     return log_spec;
 };
 
-const hzToMel = (freq: number) => {
-    // Fill in the linear part
-    const f_min = 0.0;
-    const f_sp = 200.0 / 3;
-
-    let mel = (freq - f_min) / f_sp;
-
-    // Fill in the log-scale part
-    const min_log_hz = 1000.0; // beginning of log region (Hz)
-    const min_log_mel = (min_log_hz - f_min) / f_sp; // same (Mels)
-    const logstep = Math.log(6.4) / 27.0; // step size for log region
-
-    if (freq >= min_log_hz) {
-        mel = min_log_mel + Math.log(freq / min_log_hz) / logstep;
-    }
-
-    return mel;
-};
-
-const melToHz = (mel: number) => {
-    const f_min = 0.0;
-    const f_sp = 200.0 / 3;
-    let freq = f_min + f_sp * mel;
-
-    // And now the nonlinear scale
-    const min_log_hz = 1000.0; // beginning of log region (Hz)
-    const min_log_mel = (min_log_hz - f_min) / f_sp; // same (Mels)
-    const logstep = Math.log(6.4) / 27.0; // step size for log region
-
-    if (mel >= min_log_mel) {
-        // If we have scalar data, check directly
-        freq = min_log_hz * Math.exp(logstep * (mel - min_log_mel));
-    }
-    return freq;
-};
-
-export { unitType, freqType, fixWindow, amplitudeToDb, hzToMel, melToHz };
+export { unitType, freqType, fixWindow, amplitudeToDb };