Update comments

src/ui/component/sequencer/SeqTrackContentViewer.cpp

@@ -35,6 +35,11 @@ SeqTrackContentViewer::SeqTrackContentViewer() {
 
  /** Data Update Timer */
  this->blockImageUpdateTimer = std::make_unique<DataImageUpdateTimer>(this);
+ /**
+ * To fix the bug in AudioExtractor.
+ * This will invoke AudioExtractor::extractAsync(...) every period of time.
+ * I currently do not have a better solution.
+ */
  this->blockImageUpdateTimer->startTimer(5000);
 }
 

src/ui/misc/AudioExtractor.cpp

@@ -143,6 +143,14 @@ void AudioExtractorJob::reallocResultUnsafe() {
 void AudioExtractor::extractAsync(const void* ticket,
  const juce::AudioSampleBuffer& data, uint64_t pointNum,
  const Callback& callback) {
+ /**
+ * This may cause a bug when call this while AudioExtractorJob::runJob() is running between
+ * AudioExtractorJob::doExtract() and AudioExtractorJob::sendResult().
+ * The result of current async extract will be dropped.
+ * To fix this, I add a Timer in SeqTrackContentViewer to extract again every period of time.
+ * I currently do not have a better solution.
+ */
+
  /** Find */
  auto it = this->templist.find(ticket);