1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "media/formats/webm/webm_info_parser.h"
6
7#include "base/logging.h"
8#include "media/formats/webm/webm_constants.h"
9
10namespace media {
11
12// Default timecode scale if the TimecodeScale element is
13// not specified in the INFO element.
14static const int kWebMDefaultTimecodeScale = 1000000;
15
16WebMInfoParser::WebMInfoParser()
17    : timecode_scale_(-1),
18      duration_(-1) {
19}
20
21WebMInfoParser::~WebMInfoParser() {}
22
23int WebMInfoParser::Parse(const uint8* buf, int size) {
24  timecode_scale_ = -1;
25  duration_ = -1;
26
27  WebMListParser parser(kWebMIdInfo, this);
28  int result = parser.Parse(buf, size);
29
30  if (result <= 0)
31    return result;
32
33  // For now we do all or nothing parsing.
34  return parser.IsParsingComplete() ? result : 0;
35}
36
37WebMParserClient* WebMInfoParser::OnListStart(int id) { return this; }
38
39bool WebMInfoParser::OnListEnd(int id) {
40  if (id == kWebMIdInfo && timecode_scale_ == -1) {
41    // Set timecode scale to default value if it isn't present in
42    // the Info element.
43    timecode_scale_ = kWebMDefaultTimecodeScale;
44  }
45  return true;
46}
47
48bool WebMInfoParser::OnUInt(int id, int64 val) {
49  if (id != kWebMIdTimecodeScale)
50    return true;
51
52  if (timecode_scale_ != -1) {
53    DVLOG(1) << "Multiple values for id " << std::hex << id << " specified";
54    return false;
55  }
56
57  timecode_scale_ = val;
58  return true;
59}
60
61bool WebMInfoParser::OnFloat(int id, double val) {
62  if (id != kWebMIdDuration) {
63    DVLOG(1) << "Unexpected float for id" << std::hex << id;
64    return false;
65  }
66
67  if (duration_ != -1) {
68    DVLOG(1) << "Multiple values for duration.";
69    return false;
70  }
71
72  duration_ = val;
73  return true;
74}
75
76bool WebMInfoParser::OnBinary(int id, const uint8* data, int size) {
77  if (id == kWebMIdDateUTC) {
78    if (size != 8)
79      return false;
80
81    int64 date_in_nanoseconds = 0;
82    for (int i = 0; i < size; ++i)
83      date_in_nanoseconds = (date_in_nanoseconds << 8) | data[i];
84
85    base::Time::Exploded exploded_epoch;
86    exploded_epoch.year = 2001;
87    exploded_epoch.month = 1;
88    exploded_epoch.day_of_month = 1;
89    exploded_epoch.hour = 0;
90    exploded_epoch.minute = 0;
91    exploded_epoch.second = 0;
92    exploded_epoch.millisecond = 0;
93    date_utc_ = base::Time::FromUTCExploded(exploded_epoch) +
94        base::TimeDelta::FromMicroseconds(date_in_nanoseconds / 1000);
95  }
96  return true;
97}
98
99bool WebMInfoParser::OnString(int id, const std::string& str) {
100  return true;
101}
102
103}  // namespace media
104