cast: cleanup rtp header and parsing

media/cast/net/rtp/rtp_defines.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#ifndef MEDIA_CAST_NET_RTP_RTP_DEFINES_H_
+#define MEDIA_CAST_NET_RTP_RTP_DEFINES_H_
+
+#include "base/basictypes.h"
+#include "media/cast/net/rtcp/rtcp_defines.h"
+
 namespace media {
 namespace cast {
 
 static const uint16 kRtpHeaderLength = 12;
 static const uint16 kCastHeaderLength = 7;
 static const uint8 kRtpExtensionBitMask = 0x10;
 static const uint8 kCastKeyFrameBitMask = 0x80;
 static const uint8 kCastReferenceFrameIdBitMask = 0x40;
 static const uint8 kRtpMarkerBitMask = 0x80;
+static const uint8 kRtpNumCsrcsMask = 0x0f;
 static const uint8 kCastExtensionCountmask = 0x3f;
 
 // Cast RTP extensions.
 static const uint8 kCastRtpExtensionAdaptiveLatency = 1;
 
+const uint32 kCastRtpHeaderLength = 7;
+const uint32 kGenericRtpHeaderLength = 12;
+
+struct RtpCastHeader {
+  RtpCastHeader();
+  // Elements from RTP packet header.
+  bool marker;
+  uint8 payload_type;
+  uint16 sequence_number;
+  uint32 rtp_timestamp;
+  uint32 sender_ssrc;
+  uint8 num_csrcs;
+
+  // Elements from Cast header (at beginning of RTP payload).
+  bool is_key_frame;
+  bool is_reference;
+  uint32 frame_id;
+  uint16 packet_id;
+  uint16 max_packet_id;
+  uint32 reference_frame_id;
+  uint16 new_playout_delay_ms;
+};
+
+class RtpPayloadFeedback {
+ public:
+  virtual void CastFeedback(const RtcpCastMessage& cast_feedback) = 0;
+
+ protected:
+  virtual ~RtpPayloadFeedback();
+};
+
 }  // namespace cast
 }  // namespace media
+
+#endif  // MEDIA_CAST_NET_RTP_RTP_DEFINES_H_