ffmpegdecoder: improved index reliability

2020-02-15 23:39:33 +11:00
parent 53106e1847
commit 3efbcc28ef
5 changed files with 79 additions and 49 deletions
@@ -292,31 +292,7 @@ FramePtr FFmpegDecoder::RetrieveVideo(const rational &timecode)
          input_linesize[i] = frame_->linesize[i];
        }

-        QFile save_frame(GetIndexFilename().append(QString::number(frame_->pts)));
-        if (save_frame.open(QFile::WriteOnly)) {
-
-          // Save frame to media index
-          int cached_buffer_sz = av_image_get_buffer_size(static_cast<AVPixelFormat>(frame_->format),
-                                                          frame_->width,
-                                                          frame_->height,
-                                                          1);
-
-          QByteArray cached_frame(cached_buffer_sz, Qt::Uninitialized);
-
-          av_image_copy_to_buffer(reinterpret_cast<uint8_t*>(cached_frame.data()),
-                                  cached_frame.size(),
-                                  frame_->data,
-                                  frame_->linesize,
-                                  static_cast<AVPixelFormat>(frame_->format),
-                                  frame_->width,
-                                  frame_->height,
-                                  1);
-
-          save_frame.write(qCompress(cached_frame, 1));
-          save_frame.close();
-
-          DiskManager::instance()->CreatedFile(save_frame.fileName(), QByteArray());
-        }
+        CacheFrameToDisk(frame_);
        break;
      }
    }
@@ -887,6 +863,8 @@ void FFmpegDecoder::UnconditionalVideoIndex(AVPacket* pkt, AVFrame* frame)
    ret = GetFrame(pkt, frame);

    if (ret >= 0) {
+      //CacheFrameToDisk(frame);
+
      video_stream->append_frame_index(frame->pts);
    } else {
      // Assume we've reached the end of the file
@@ -894,6 +872,8 @@ void FFmpegDecoder::UnconditionalVideoIndex(AVPacket* pkt, AVFrame* frame)
    }
  }

+  video_stream->append_frame_index(VideoStream::kEndTimestamp);
+
  // Save index to file
  if (!video_stream->save_frame_index(GetIndexFilename())) {
    qWarning() << QStringLiteral("Failed to save index for %1").arg(stream()->footage()->filename());
@@ -953,25 +933,19 @@ int64_t FFmpegDecoder::GetClosestTimestampInIndex(const int64_t &ts)

  bool index_is_being_created = false;

-  // Check if the frame index has been populated
-  if (video_stream->is_frame_index_empty()) {
+  // Check if an index is being created right now
+  if (video_stream->index_process_lock()->tryLock()) {

-    // If not, check if one is being created right now
-    if (video_stream->index_process_lock()->tryLock()) {
-
-      // If not, make an index
+    // If not, check if the frame index has been populated
+    if (!video_stream->is_frame_index_ready()) {
+      // If not, make a frame index
      ValidateVideoIndex();
-
-      video_stream->index_process_lock()->unlock();
-
-      // If the index is still empty, the video must just be empty
-      if (video_stream->is_frame_index_empty()) {
-        return -1;
-      }
-    } else {
-      // The index is being created in another thread, wait until we have more information
-      index_is_being_created = true;
    }
+
+    video_stream->index_process_lock()->unlock();
+
+  } else {
+    index_is_being_created = true;
  }

  int64_t closest_ts = -1;
@@ -987,7 +961,7 @@ int64_t FFmpegDecoder::GetClosestTimestampInIndex(const int64_t &ts)

    closest_ts = video_stream->get_closest_timestamp_in_frame_index(ts);

-  } while (index_is_being_created);
+  } while (closest_ts < 0 && index_is_being_created);

  return closest_ts;
 }
@@ -996,11 +970,11 @@ void FFmpegDecoder::ValidateVideoIndex()
 {
  VideoStreamPtr video_stream = std::static_pointer_cast<VideoStream>(stream());

-  if (video_stream->is_frame_index_empty()) {
+  if (!video_stream->is_frame_index_ready()) {
    video_stream->load_frame_index(GetIndexFilename());
  }

-  if (video_stream->is_frame_index_empty()) {
+  if (!video_stream->is_frame_index_ready()) {
    // Reset state
    Seek(0);

@@ -1015,3 +989,32 @@ void FFmpegDecoder::Seek(int64_t timestamp)
  avcodec_flush_buffers(codec_ctx_);
  av_seek_frame(fmt_ctx_, avstream_->index, timestamp, AVSEEK_FLAG_BACKWARD);
 }
+
+void FFmpegDecoder::CacheFrameToDisk(AVFrame *f)
+{
+  QFile save_frame(GetIndexFilename().append(QString::number(f->pts)));
+  if (save_frame.open(QFile::WriteOnly)) {
+
+    // Save frame to media index
+    int cached_buffer_sz = av_image_get_buffer_size(static_cast<AVPixelFormat>(f->format),
+                                                    f->width,
+                                                    f->height,
+                                                    1);
+
+    QByteArray cached_frame(cached_buffer_sz, Qt::Uninitialized);
+
+    av_image_copy_to_buffer(reinterpret_cast<uint8_t*>(cached_frame.data()),
+                            cached_frame.size(),
+                            f->data,
+                            f->linesize,
+                            static_cast<AVPixelFormat>(f->format),
+                            f->width,
+                            f->height,
+                            1);
+
+    save_frame.write(qCompress(cached_frame, 1));
+    save_frame.close();
+
+    DiskManager::instance()->CreatedFile(save_frame.fileName(), QByteArray());
+  }
+}
@@ -119,6 +119,8 @@ private:

  void Seek(int64_t timestamp);

+  void CacheFrameToDisk(AVFrame* f);
+
  AVFormatContext* fmt_ctx_;
  AVCodecContext* codec_ctx_;
  AVStream* avstream_;
@@ -22,6 +22,8 @@

 #include <QFile>

+const int64_t VideoStream::kEndTimestamp = AV_NOPTS_VALUE;
+
 VideoStream::VideoStream()
 {
  set_type(kVideo);
@@ -48,12 +50,22 @@ int64_t VideoStream::get_closest_timestamp_in_frame_index(const int64_t &ts)
 {
  QMutexLocker locker(&index_access_lock_);

+  if (frame_index_.isEmpty()) {
+    return -1;
+  }
+
  if (ts <= 0) {
    return frame_index_.first();
  }

+  int index_size = frame_index_.size();
+
+  if (frame_index_.last() == kEndTimestamp) {
+    index_size--;
+  }
+
  // Use index to find closest frame in file
-  for (int i=0;i<frame_index_.size();i++) {
+  for (int i=0;i<index_size;i++) {
    int64_t this_ts = frame_index_.at(i);

    if (this_ts == ts) {
@@ -63,7 +75,13 @@ int64_t VideoStream::get_closest_timestamp_in_frame_index(const int64_t &ts)
    }
  }

-  return frame_index_.last();
+  if (frame_index_.last() == kEndTimestamp) {
+    // Index is done
+    return frame_index_.last();
+  } else {
+    // Index is not done yet
+    return -1;
+  }
 }

 void VideoStream::clear_frame_index()
@@ -80,11 +98,11 @@ void VideoStream::append_frame_index(const int64_t &ts)
  frame_index_.append(ts);
 }

-bool VideoStream::is_frame_index_empty()
+bool VideoStream::is_frame_index_ready()
 {
  QMutexLocker locker(&index_access_lock_);

-  return frame_index_.isEmpty();
+  return !frame_index_.isEmpty() && frame_index_.last() == VideoStream::kEndTimestamp;
 }

 int64_t VideoStream::last_frame_index_timestamp()
@@ -110,6 +128,8 @@ bool VideoStream::load_frame_index(const QString &s)
                    index_file.size());

    index_file.close();
+
+    return true;
  }

  return false;
@@ -127,6 +147,7 @@ bool VideoStream::save_frame_index(const QString &s)
                     frame_index_.size() * static_cast<int>(sizeof(int64_t)));

    index_file.close();
+
    return true;
  }

@@ -28,6 +28,8 @@ class VideoStream : public ImageStream
 public:
  VideoStream();

+  static const int64_t kEndTimestamp;
+
  virtual QString description() const override;

  /**
@@ -41,7 +43,8 @@ public:
  int64_t get_closest_timestamp_in_frame_index(const int64_t& ts);
  void clear_frame_index();
  void append_frame_index(const int64_t& ts);
-  bool is_frame_index_empty();
+  //bool is_frame_index_empty();
+  bool is_frame_index_ready();
  int64_t last_frame_index_timestamp();

  bool load_frame_index(const QString& s);
@@ -75,6 +75,7 @@ void TaskManager::CreateInstance()
 void TaskManager::DestroyInstance()
 {
  delete instance_;
+  instance_ = nullptr;
 }

 TaskManager *TaskManager::instance()