Exemplo n.º 1
0
SoundSource::OpenResult SoundSourceMp3::tryOpen(const AudioSourceConfig& /*audioSrcCfg*/) {
    DEBUG_ASSERT(!hasChannelCount());
    DEBUG_ASSERT(!hasSamplingRate());

    DEBUG_ASSERT(!m_file.isOpen());
    if (!m_file.open(QIODevice::ReadOnly)) {
        qWarning() << "Failed to open file:" << m_file.fileName();
        return OpenResult::FAILED;
    }

    // Get a pointer to the file using memory mapped IO
    m_fileSize = m_file.size();
    m_pFileData = m_file.map(0, m_fileSize);
    // NOTE(uklotzde): If the file disappears unexpectedly while mapped
    // a SIGBUS error might occur that is not handled and will terminate
    // Mixxx immediately. This behavior is documented in the manpage of
    // mmap(). It has already appeared due to hardware errors and is
    // described in the following bug report:
    // https://bugs.launchpad.net/mixxx/+bug/1452005

    // Transfer it to the mad stream-buffer:
    mad_stream_options(&m_madStream, MAD_OPTION_IGNORECRC);
    mad_stream_buffer(&m_madStream, m_pFileData, m_fileSize);
    DEBUG_ASSERT(m_pFileData == m_madStream.this_frame);

    DEBUG_ASSERT(m_seekFrameList.empty());
    m_avgSeekFrameCount = 0;
    m_curFrameIndex = getMinFrameIndex();
    int headerPerSamplingRate[kSamplingRateCount];
    for (int i = 0; i < kSamplingRateCount; ++i) {
        headerPerSamplingRate[i] = 0;
    }

    // Decode all the headers and calculate audio properties

    unsigned long sumBitrate = 0;

    mad_header madHeader;
    mad_header_init(&madHeader);

    SINT maxChannelCount = getChannelCount();
    do {
        if (!decodeFrameHeader(&madHeader, &m_madStream, true)) {
            if (isStreamValid(m_madStream)) {
                // Skip frame
                continue;
            } else {
                // Abort decoding
                break;
            }
        }

        // Grab data from madHeader
        const unsigned int madSampleRate = madHeader.samplerate;

        // TODO(XXX): Replace DEBUG_ASSERT with static_assert
        // MAD must not change its enum values!
        DEBUG_ASSERT(MAD_UNITS_8000_HZ == 8000);
        const mad_units madUnits = static_cast<mad_units>(madSampleRate);

        const long madFrameLength = mad_timer_count(madHeader.duration, madUnits);
        if (0 >= madFrameLength) {
            qWarning() << "Skipping MP3 frame with invalid length"
                    << madFrameLength
                    << "in:" << m_file.fileName();
            // Skip frame
            continue;
        }

        const SINT madChannelCount = MAD_NCHANNELS(&madHeader);
        if (isValidChannelCount(maxChannelCount) && (madChannelCount != maxChannelCount)) {
            qWarning() << "Differing number of channels"
                    << madChannelCount << "<>" << maxChannelCount
                    << "in some MP3 frame headers:"
                    << m_file.fileName();
        }
        maxChannelCount = math_max(madChannelCount, maxChannelCount);

        const int samplingRateIndex = getIndexBySamplingRate(madSampleRate);
        if (samplingRateIndex >= kSamplingRateCount) {
            qWarning() << "Invalid sample rate:" << m_file.fileName()
                    << madSampleRate;
            // Abort
            mad_header_finish(&madHeader);
            return OpenResult::FAILED;
        }
        // Count valid frames separated by its sampling rate
        headerPerSamplingRate[samplingRateIndex]++;

        addSeekFrame(m_curFrameIndex, m_madStream.this_frame);

        // Accumulate data from the header
        sumBitrate += madHeader.bitrate;

        // Update current stream position
        m_curFrameIndex += madFrameLength;

        DEBUG_ASSERT(m_madStream.this_frame);
        DEBUG_ASSERT(0 <= (m_madStream.this_frame - m_pFileData));
    } while (quint64(m_madStream.this_frame - m_pFileData) < m_fileSize);

    mad_header_finish(&madHeader);

    if (MAD_ERROR_NONE != m_madStream.error) {
        // Unreachable code for recoverable errors
        DEBUG_ASSERT(!MAD_RECOVERABLE(m_madStream.error));
        if (MAD_ERROR_BUFLEN != m_madStream.error) {
            qWarning() << "Unrecoverable MP3 header error:"
                    << mad_stream_errorstr(&m_madStream);
            // Abort
            return OpenResult::FAILED;
        }
    }

    if (m_seekFrameList.empty()) {
        // This is not a working MP3 file.
        qWarning() << "SSMP3: This is not a working MP3 file:"
                << m_file.fileName();
        // Abort
        return OpenResult::FAILED;
    }

    int mostCommonSamplingRateIndex = kSamplingRateCount; // invalid
    int mostCommonSamplingRateCount = 0;
    int differentRates = 0;
    for (int i = 0; i < kSamplingRateCount; ++i) {
        // Find most common sampling rate
        if (mostCommonSamplingRateCount < headerPerSamplingRate[i]) {
            mostCommonSamplingRateCount = headerPerSamplingRate[i];
            mostCommonSamplingRateIndex = i;
            differentRates++;
        }
    }

    if (differentRates > 1) {
        qWarning() << "Differing sampling rate in some headers:"
                   << m_file.fileName();
        for (int i = 0; i < kSamplingRateCount; ++i) {
            if (0 < headerPerSamplingRate[i]) {
                qWarning() << headerPerSamplingRate[i] << "MP3 headers with sampling rate" << getSamplingRateByIndex(i);
            }
        }

        qWarning() << "MP3 files with varying sample rate are not supported!";
        qWarning() << "Since this happens most likely due to a corrupt file";
        qWarning() << "Mixxx tries to plays it with the most common sample rate for this file";
    }

    if (mostCommonSamplingRateIndex < kSamplingRateCount) {
        setSamplingRate(getSamplingRateByIndex(mostCommonSamplingRateIndex));
    } else {
        qWarning() << "No single valid sampling rate in header";
        // Abort
        return OpenResult::FAILED;
    }

    // Initialize the AudioSource
    setChannelCount(maxChannelCount);
    setFrameCount(m_curFrameIndex);

    // Calculate average values
    m_avgSeekFrameCount = getFrameCount() / m_seekFrameList.size();
    const unsigned long avgBitrate = sumBitrate / m_seekFrameList.size();
    setBitrate(avgBitrate / 1000);

    // Terminate m_seekFrameList
    addSeekFrame(m_curFrameIndex, 0);

    // Reset positions
    m_curFrameIndex = getMinFrameIndex();

    // Restart decoding at the beginning of the audio stream
    m_curFrameIndex = restartDecoding(m_seekFrameList.front());
    if (m_curFrameIndex != m_seekFrameList.front().frameIndex) {
        qWarning() << "Failed to start decoding:" << m_file.fileName();
        // Abort
        return OpenResult::FAILED;
    }

    return OpenResult::SUCCEEDED;
}
Exemplo n.º 2
0
void SoundSourceFLAC::flacMetadata(const FLAC__StreamMetadata* metadata) {
    // https://xiph.org/flac/api/group__flac__stream__decoder.html#ga43e2329c15731c002ac4182a47990f85
    // "...one STREAMINFO block, followed by zero or more other metadata blocks."
    // "...by default the decoder only calls the metadata callback for the STREAMINFO block..."
    // "...always before the first audio frame (i.e. write callback)."
    switch (metadata->type) {
    case FLAC__METADATA_TYPE_STREAMINFO:
    {
        const SINT channelCount = metadata->data.stream_info.channels;
        if (isValidChannelCount(channelCount)) {
            if (hasChannelCount()) {
                // already set before -> check for consistency
                if (getChannelCount() != channelCount) {
                    qWarning() << "Unexpected channel count:"
                            << channelCount << " <> " << getChannelCount();
                }
            } else {
                // not set before
                setChannelCount(channelCount);
            }
        } else {
            qWarning() << "Invalid channel count:"
                    << channelCount;
        }
        const SINT samplingRate = metadata->data.stream_info.sample_rate;
        if (isValidSamplingRate(samplingRate)) {
            if (hasSamplingRate()) {
                // already set before -> check for consistency
                if (getSamplingRate() != samplingRate) {
                    qWarning() << "Unexpected sampling rate:"
                            << samplingRate << " <> " << getSamplingRate();
                }
            } else {
                // not set before
                setSamplingRate(samplingRate);
            }
        } else {
            qWarning() << "Invalid sampling rate:"
                    << samplingRate;
        }
        const SINT frameCount = metadata->data.stream_info.total_samples;
        DEBUG_ASSERT(isValidFrameCount(frameCount));
        if (isEmpty()) {
            // not set before
            setFrameCount(frameCount);
        } else {
            // already set before -> check for consistency
            if (getFrameCount() != frameCount) {
                qWarning() << "Unexpected frame count:"
                        << frameCount << " <> " << getFrameCount();
            }
        }
        const unsigned bitsPerSample = metadata->data.stream_info.bits_per_sample;
        DEBUG_ASSERT(kBitsPerSampleDefault != bitsPerSample);
        if (kBitsPerSampleDefault == m_bitsPerSample) {
            // not set before
            m_bitsPerSample = bitsPerSample;
            m_sampleScaleFactor = CSAMPLE_PEAK
                    / CSAMPLE(FLAC__int32(1) << bitsPerSample);
        } else {
            // already set before -> check for consistency
            if (bitsPerSample != m_bitsPerSample) {
                qWarning() << "Unexpected bits per sample:"
                        << bitsPerSample << " <> " << m_bitsPerSample;
            }
        }
        m_maxBlocksize = metadata->data.stream_info.max_blocksize;
        if (0 >= m_maxBlocksize) {
            qWarning() << "Invalid max. blocksize" << m_maxBlocksize;
        }
        const SINT sampleBufferCapacity =
                m_maxBlocksize * getChannelCount();
        m_sampleBuffer.resetCapacity(sampleBufferCapacity);
        break;
    }
    default:
        // Ignore all other metadata types
        break;
    }
}