DrKLO/Telegram · warning · UnhandledAudioFormatException

Unhandled format: {inputAudioFormat}

Error message

Unhandled format: {inputAudioFormat}

What it means

SilenceSkippingAudioProcessor.onConfigure throws UnhandledAudioFormatException when the input encoding is not C.ENCODING_PCM_16BIT. This processor detects and removes silence runs using 16-bit amplitude heuristics; it only operates on 16-bit PCM. Other encodings (8/24/32-bit, float, compressed) lack the amplitude semantics the algorithm assumes and are rejected so the pipeline can bypass the processor or convert the input first.

Source

Thrown at TMessagesProj/src/main/java/com/google/android/exoplayer2/audio/SilenceSkippingAudioProcessor.java:151

    this.enabled = enabled;
  }

  /**
   * Returns the total number of frames of input audio that were skipped due to being classified as
   * silence since the last call to {@link #flush()}.
   */
  public long getSkippedFrames() {
    return skippedFrames;
  }

  // AudioProcessor implementation.

  @Override
  @CanIgnoreReturnValue
  public AudioFormat onConfigure(AudioFormat inputAudioFormat)
      throws UnhandledAudioFormatException {
    if (inputAudioFormat.encoding != C.ENCODING_PCM_16BIT) {
      throw new UnhandledAudioFormatException(inputAudioFormat);
    }
    return enabled ? inputAudioFormat : AudioFormat.NOT_SET;
  }

  @Override
  public boolean isActive() {
    return enabled;
  }

  @Override
  public void queueInput(ByteBuffer inputBuffer) {
    while (inputBuffer.hasRemaining() && !hasPendingOutput()) {
      switch (state) {
        case STATE_NOISY:
          processNoisy(inputBuffer);
          break;
        case STATE_MAYBE_SILENT:
          processMaybeSilence(inputBuffer);

View on GitHub (pinned to 45ab8f4308)

Solutions

1. Disable silence skipping (setEnabled(false), leave pending null) when the source encoding is not 16-bit PCM; insert a ResamplingAudioProcessor upstream to down-convert to 16-bit first.
2. Gate enabling on the current AudioFormat: only setEnabled(true) when inputAudioFormat.encoding == C.ENCODING_PCM_16BIT.
3. If silence removal is needed for hi-res sources, run it after a down-conversion step rather than on the native hi-res stream.

Example fix

// before
silenceSkippingProcessor.setEnabled(true); // always on
// source is 24-bit PCM -> onConfigure throws
// after
if (inputAudioFormat.encoding == C.ENCODING_PCM_16BIT) {
  silenceSkippingProcessor.setEnabled(true);
} else {
  silenceSkippingProcessor.setEnabled(false); // bypass, or resample to 16-bit first
}

if (inputAudioFormat.encoding == C.ENCODING_PCM_16BIT) {
  silenceSkippingProcessor.setEnabled(true);
} else {
  silenceSkippingProcessor.setEnabled(false);
}

try {
  silenceSkippingProcessor.onConfigure(inputAudioFormat);
} catch (UnhandledAudioFormatException e) {
  silenceSkippingProcessor.setEnabled(false); // bypass for non-16-bit
}

When it happens

Trigger: Enabling silence skipping (setEnabled(true) / set it pending) while the source is non-16-bit PCM — e.g. hi-res 24-bit FLAC, float PCM from a float decoder, or compressed audio routed incorrectly; a format switch mid-stream to a non-16-bit encoding with silence skipping left on.

Common situations: Default audio chain enabling silence skipping for all sources; playing hi-res audio where the decoder outputs 24/32-bit or float; toggling silence skipping at runtime without checking the current encoding.

Related errors

• Unhandled format: {inputAudioFormat}
• Unhandled format: {inputAudioFormat}
• Unhandled format: {inputAudioFormat}
• Unhandled format: {inputAudioFormat}
• Invalid output encoding (mode={outputMode}) for: {inputForma

AI-assisted analysis of DrKLO/Telegram@45ab8f4308 (2026-08-14). Data as JSON: /api/errors/b695fb68276fdb81. Report an issue: GitHub.