Request keyframe if too many packets are missing and NACK is disabled.

webrtc/modules/video_coding/main/source/jitter_buffer.h

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 208 matching lines @@
   // |decoded_state|.
   void FindAndInsertContinuousFramesWithState(
       const VCMDecodingState& decoded_state)
       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   // Looks for frames in |incomplete_frames_| which are continuous in
   // |last_decoded_state_| taking all decodable frames into account. Starts
   // the search from |new_frame|.
   void FindAndInsertContinuousFrames(const VCMFrameBuffer& new_frame)
       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   VCMFrameBuffer* NextFrame() const EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
-  // Returns true if the NACK list was updated to cover sequence numbers up to
-  // |sequence_number|. If false a key frame is needed to get into a state where
-  // we can continue decoding.
-  bool UpdateNackList(uint16_t sequence_number)
+  // Returns true if sequence numbers are covered up to |sequence_number|. The
+  // NACK list will be used to handle missing packets if enabled.
+  // Returns false if a key frame is needed to get into a state where we can
+  // continue decoding. Without NACK this is always the case if packets are
+  // missing.
+  bool CoverSequenceUpTo(uint16_t sequence_number)
       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   bool TooLargeNackList() const;
   // Returns true if the NACK list was reduced without problem. If false a key
   // frame is needed to get into a state where we can continue decoding.
   bool HandleTooLargeNackList() EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   bool MissingTooOldPacket(uint16_t latest_sequence_number) const
       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   // Returns true if the too old packets was successfully removed from the NACK
   // list. If false, a key frame is needed to get into a state where we can
   // continue decoding.
@@ skipping 111 matching lines @@
   // Estimated rolling average of packets per frame
   float average_packets_per_frame_;
   // average_packets_per_frame converges fast if we have fewer than this many
   // frames.
   int frame_counter_;
   DISALLOW_COPY_AND_ASSIGN(VCMJitterBuffer);
 };
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_VIDEO_CODING_MAIN_SOURCE_JITTER_BUFFER_H_