| # 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. |
| |
| """Parses protobuf RTC dumps.""" |
| |
| from __future__ import division |
| import struct |
| import pyproto.webrtc.call.rtc_event_log_pb2 as rtc_pb |
| |
| |
| class DataPoint(object): |
| """Simple container class for RTP events.""" |
| |
| def __init__(self, rtp_header_str, packet_size, |
| arrival_timestamp_us): |
| """Builds a data point by parsing an RTP header, size and arrival time. |
| |
| RTP header structure is defined in RFC 3550 section 5.1. |
| """ |
| self.size = packet_size |
| self.arrival_timestamp_ms = arrival_timestamp_us / 1000 |
| header = struct.unpack_from("!HHII", rtp_header_str, 0) |
| (first2header_bytes, self.sequence_number, self.timestamp, |
| self.ssrc) = header |
| self.payload_type = first2header_bytes & 0b01111111 |
| self.marker_bit = (first2header_bytes & 0b10000000) >> 7 |
| |
| |
| def parse_protobuf(file_path): |
| """Parses RTC event log from protobuf file. |
| |
| Args: |
| file_path: path to protobuf file of RTC event stream |
| |
| Returns: |
| all RTP packet events from the event stream as a list of DataPoints |
| """ |
| event_stream = rtc_pb.EventStream() |
| with open(file_path, "rb") as f: |
| event_stream.ParseFromString(f.read()) |
| |
| return [DataPoint(event.rtp_packet.header, |
| event.rtp_packet.packet_length, |
| event.timestamp_us) |
| for event in event_stream.stream |
| if event.HasField("rtp_packet")] |
