blob: 466e3df49e5ab349b965490712d7e1b1b97c5a28 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
|
// Copyright 2015 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 CAST_STREAMING_CONSTANTS_H_
#define CAST_STREAMING_CONSTANTS_H_
////////////////////////////////////////////////////////////////////////////////
// NOTE: This file should only contain constants that are reasonably globally
// used (i.e., by many modules, and in all or nearly all subdirs). Do NOT add
// non-POD constants, functions, interfaces, or any logic to this module.
////////////////////////////////////////////////////////////////////////////////
#include <chrono>
#include <ratio>
namespace openscreen {
namespace cast {
// Default target playout delay. The playout delay is the window of time between
// capture from the source until presentation at the receiver.
constexpr std::chrono::milliseconds kDefaultTargetPlayoutDelay(400);
// Target number of milliseconds between the sending of RTCP reports. Both
// senders and receivers regularly send RTCP reports to their peer.
constexpr std::chrono::milliseconds kRtcpReportInterval(500);
// This is an important system-wide constant. This limits how much history
// the implementation must retain in order to process the acknowledgements of
// past frames.
//
// This value is carefully choosen such that it fits in the 8-bits range for
// frame IDs. It is also less than half of the full 8-bits range such that
// logic can handle wrap around and compare two frame IDs meaningfully.
constexpr int kMaxUnackedFrames = 120;
// The network must support a packet size of at least this many bytes.
constexpr int kRequiredNetworkPacketSize = 256;
// The spec declares RTP timestamps must always have a timebase of 90000 ticks
// per second for video.
using kVideoTimebase = std::ratio<1, 90000>;
} // namespace cast
} // namespace openscreen
#endif // CAST_STREAMING_CONSTANTS_H_
|
