webrtc / src / 63fb95a68d70cd7036db65c3378e91cb77faa44d / . / webrtc / tools / py_event_log_analyzer / misc.py

# Copyright (c) 2016 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. | |

"""Utility functions for calculating statistics. | |

""" | |

from __future__ import division | |

import collections | |

import sys | |

def count_reordered(sequence_numbers): | |

"""Returns number of reordered indices. | |

A reordered index is an index `i` for which sequence_numbers[i] >= | |

sequence_numbers[i + 1] | |

""" | |

return sum(1 for (s1, s2) in zip(sequence_numbers, | |

sequence_numbers[1:]) if | |

s1 >= s2) | |

def ssrc_normalized_size_table(data_points): | |

"""Counts proportion of data for every SSRC. | |

Args: | |

data_points: list of pb_parse.DataPoint | |

Returns: | |

A dictionary mapping from every SSRC in the data points. The | |

value of an SSRC `s` is the proportion of sizes of packets with | |

SSRC `s` to the total size of all packets. | |

""" | |

mapping = collections.defaultdict(int) | |

for point in data_points: | |

mapping[point.ssrc] += point.size | |

return normalize_counter(mapping) | |

def normalize_counter(counter): | |

"""Returns a normalized version of the dictionary `counter`. | |

Does not modify `counter`. | |

Returns: | |

A new dictionary, in which every value in `counter` | |

has been divided by the total to sum up to 1. | |

""" | |

total = sum(counter.values()) | |

return {key: counter[key] / total for key in counter} | |

def unwrap(data, mod): | |

"""Returns `data` unwrapped modulo `mod`. Does not modify data. | |

Adds integer multiples of mod to all elements of data except the | |

first, such that all pairs of consecutive elements (a, b) satisfy | |

-mod / 2 <= b - a < mod / 2. | |

E.g. unwrap([0, 1, 2, 0, 1, 2, 7, 8], 3) -> [0, 1, 2, 3, | |

4, 5, 4, 5] | |

""" | |

lst = data[:] | |

for i in range(1, len(data)): | |

lst[i] = lst[i - 1] + (lst[i] - lst[i - 1] + | |

mod // 2) % mod - (mod // 2) | |

return lst | |

# Python 2/3-compatible input function | |

if sys.version_info[0] <= 2: | |

get_input = raw_input | |

else: | |

get_input = input |