google/ExoPlayer · critical · FfmpegDecoderException

Initialization failed.

Error message

Initialization failed.

What it means

FfmpegDecoderException ('Initialization failed.') thrown when the native ffmpegInitialize(...) returns 0, i.e. avcodec/FFmpeg could not create a decoder context for the requested codec. By this point the native library IS loaded (that was checked first), so the failure is codec- or stream-specific: unsupported codec configuration, invalid extra data, or native allocation failure.

Source

Thrown at extensions/ffmpeg/src/main/java/com/google/android/exoplayer2/ext/ffmpeg/FfmpegAudioDecoder.java:79

      Format format,
      int numInputBuffers,
      int numOutputBuffers,
      int initialInputBufferSize,
      boolean outputFloat)
      throws FfmpegDecoderException {
    super(new DecoderInputBuffer[numInputBuffers], new SimpleDecoderOutputBuffer[numOutputBuffers]);
    if (!FfmpegLibrary.isAvailable()) {
      throw new FfmpegDecoderException("Failed to load decoder native libraries.");
    }
    Assertions.checkNotNull(format.sampleMimeType);
    codecName = Assertions.checkNotNull(FfmpegLibrary.getCodecName(format.sampleMimeType));
    extraData = getExtraData(format.sampleMimeType, format.initializationData);
    encoding = outputFloat ? C.ENCODING_PCM_FLOAT : C.ENCODING_PCM_16BIT;
    outputBufferSize = outputFloat ? OUTPUT_BUFFER_SIZE_32BIT : OUTPUT_BUFFER_SIZE_16BIT;
    nativeContext =
        ffmpegInitialize(codecName, extraData, outputFloat, format.sampleRate, format.channelCount);
    if (nativeContext == 0) {
      throw new FfmpegDecoderException("Initialization failed.");
    }
    setInitialInputBufferSize(initialInputBufferSize);
  }

  @Override
  public String getName() {
    return "ffmpeg" + FfmpegLibrary.getVersion() + "-" + codecName;
  }

  @Override
  protected DecoderInputBuffer createInputBuffer() {
    return new DecoderInputBuffer(
        DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_DIRECT,
        FfmpegLibrary.getInputBufferPaddingSize());
  }

  @Override
  protected SimpleDecoderOutputBuffer createOutputBuffer() {

View on GitHub (pinned to dd430f7053)

Solutions

1. Confirm the codec is actually in your FFmpeg build (FfmpegLibrary.supportsFormat(mime) and the build flags used for the natives)
2. Inspect the Format: sampleRate, channelCount and initializationData must be populated correctly by the extractor for that container
3. Catch FfmpegDecoderException and let the renderer fall back to the platform decoder for that format
4. Free decoder instances and retry if the device is under native memory pressure

Example fix

// before
FfmpegAudioDecoder decoder = new FfmpegAudioDecoder(format, numIn, numOut, initialSize, outputFloat);

// after: guard support and fall back
if (FfmpegLibrary.isAvailable()
    && FfmpegLibrary.supportsFormat(format.sampleMimeType)) {
  try {
    decoder = new FfmpegAudioDecoder(format, numIn, numOut, initialSize, outputFloat);
  } catch (FfmpegDecoderException e) {
    Log.e(TAG, "ffmpeg init failed for " + format.sampleMimeType, e);
    decoder = null; // renderer falls through to MediaCodec
  }
}

if (format.sampleMimeType != null
    && FfmpegLibrary.isAvailable()
    && FfmpegLibrary.supportsFormat(format.sampleMimeType)
    && format.sampleRate != Format.NO_VALUE
    && format.channelCount != Format.NO_VALUE) {
  // codec is in the build and format is well-formed; init failure is now unlikely
  decoder = new FfmpegAudioDecoder(format, numIn, numOut, initialSize, outputFloat);
}

try {
  decoder = new FfmpegAudioDecoder(format, numIn, numOut, initialSize, outputFloat);
} catch (FfmpegDecoderException e) {
  if ("Initialization failed.".equals(e.getMessage())) {
    // codec-specific init failed: log format details and fall back to MediaCodec
    Log.e(TAG, "ffmpeg init failed for " + format.sampleMimeType, e);
    decoder = null;
  } else {
    throw e;
  }
}

When it happens

Trigger: Initializing FfmpegAudioDecoder for a sample MIME type whose FFmpeg build lacks the codec; format.initializationData (codec-specific extradata, e.g. AAC AudioSpecificConfig) malformed or absent; channelCount/sampleRate zero or nonsensical in the Format; native memory pressure during avcodec_open.

Common situations: Custom FFmpeg builds compiled without the needed decoders (--disable-everything minus the codec list); broken streams created by non-standard muxers; device memory exhaustion when many decoders open.

Related errors

• Failed to initialize decoder. Error: ${gav1GetErrorMessage(g
• Failed to load decoder native libraries.
• Failed to load decoder native library.
• Buffer render error: ${gav1GetErrorMessage(gav1DecoderContex
• Initialization data must be of length 1

AI-assisted analysis of google/ExoPlayer@dd430f7053 (2026-08-14). Data as JSON: /api/errors/947d7f857105c7d2. Report an issue: GitHub.