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
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
  133
  134
  135
  136
  137
  138
  139
  140
  141
  142
  143
  144
  145
  146
  147
  148
  149
  150
  151
  152
  153
  154
  155
  156
  157
  158
  159
  160
  161
  162
  163
  164
  165
  166
  167
  168
  169
  170
  171
  172
  173
  174
  175
  176
  177
  178
  179
  180
  181
  182
  183
  184
  185
  186
  187

media / capabilities / webrtc_video_stats_db.cc [blame]

// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

#include "media/capabilities/webrtc_video_stats_db.h"

#include "base/check_op.h"
#include "base/format_macros.h"
#include "base/metrics/field_trial_params.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/stringprintf.h"
#include "media/base/media_switches.h"
#include "media/capabilities/bucket_utility.h"

namespace media {

namespace {
// Default value for maximum number of days until a stats entry is considered
// expired.
constexpr int kMaxDaysToKeepStatsDefault = 30;
// Default value for maximum number of stats entries per config.
constexpr int kMaxEntriesPerConfigDefault = 10;
// Field trial parameter names.
constexpr char kMaxDaysToKeepStatsParamName[] = "db_days_to_keep_stats";
constexpr char kMaxEntriesPerConfigParamName[] = "db_max_entries_per_cpnfig";

// Group similar codec profiles to the same entry. Returns
// VIDEO_CODEC_PROFILE_UNKNOWN if `codec_profile` is outside the valid range or
// not tracked. The reason to not track all codec profiles is to limit the
// fingerprinting surface.
VideoCodecProfile GetWebrtcCodecProfileBucket(VideoCodecProfile codec_profile) {
  if (codec_profile >= H264PROFILE_MIN && codec_profile <= H264PROFILE_MAX) {
    return H264PROFILE_MIN;
  }
  if (codec_profile >= VP8PROFILE_MIN && codec_profile <= VP8PROFILE_MAX) {
    return VP8PROFILE_MIN;
  }
  if (codec_profile == VP9PROFILE_PROFILE0) {
    return VP9PROFILE_PROFILE0;
  }
  if (codec_profile == VP9PROFILE_PROFILE2) {
    return VP9PROFILE_PROFILE2;
  }
  if (codec_profile >= AV1PROFILE_MIN && codec_profile <= AV1PROFILE_MAX) {
    return AV1PROFILE_MIN;
  }
  return VIDEO_CODEC_PROFILE_UNKNOWN;
}

}  // namespace

// static
WebrtcVideoStatsDB::VideoDescKey
WebrtcVideoStatsDB::VideoDescKey::MakeBucketedKey(
    bool is_decode_stats,
    VideoCodecProfile codec_profile,
    bool hardware_accelerated,
    int pixels) {
  // Bucket pixel size to prevent an explosion of one-off values in the
  // database and add basic guards against fingerprinting.
  return VideoDescKey(is_decode_stats,
                      GetWebrtcCodecProfileBucket(codec_profile),
                      hardware_accelerated, GetWebrtcPixelsBucket(pixels));
}

WebrtcVideoStatsDB::VideoDescKey::VideoDescKey(bool is_decode_stats,
                                               VideoCodecProfile codec_profile,
                                               bool hardware_accelerated,
                                               int pixels)
    : is_decode_stats(is_decode_stats),
      codec_profile(codec_profile),
      hardware_accelerated(hardware_accelerated),
      pixels(pixels) {}

std::string WebrtcVideoStatsDB::VideoDescKey::Serialize() const {
  std::string video_part = base::StringPrintf("%d|%d|%d|%d", is_decode_stats,
                                              static_cast<int>(codec_profile),
                                              hardware_accelerated, pixels);

  return video_part;
}

std::string WebrtcVideoStatsDB::VideoDescKey::SerializeWithoutPixels() const {
  std::string video_part =
      base::StringPrintf("%d|%d|%d|", is_decode_stats,
                         static_cast<int>(codec_profile), hardware_accelerated);

  return video_part;
}

std::string WebrtcVideoStatsDB::VideoDescKey::ToLogStringForDebug() const {
  return "Key {" + Serialize() + "}";
}

// static
std::optional<int> WebrtcVideoStatsDB::VideoDescKey::ParsePixelsFromKey(
    std::string key) {
  constexpr size_t kMinimumIndexOfLastSeparator = 5;
  size_t last_separator_index = key.rfind("|");
  if (last_separator_index != std::string::npos &&
      last_separator_index >= kMinimumIndexOfLastSeparator &&
      (last_separator_index + 1) < key.size()) {
    int parsed_pixels;
    if (base::StringToInt(&key.c_str()[last_separator_index + 1],
                          &parsed_pixels))
      return parsed_pixels;
  }
  return std::nullopt;
}

WebrtcVideoStatsDB::VideoStats::VideoStats(double timestamp,
                                           uint32_t frames_processed,
                                           uint32_t key_frames_processed,
                                           float p99_processing_time_ms)
    : timestamp(timestamp),
      frames_processed(frames_processed),
      key_frames_processed(key_frames_processed),
      p99_processing_time_ms(p99_processing_time_ms) {
  DCHECK_GE(frames_processed, 0u);
  DCHECK_GE(key_frames_processed, 0u);
  DCHECK_GE(p99_processing_time_ms, 0);
}

WebrtcVideoStatsDB::VideoStats::VideoStats(uint32_t frames_processed,
                                           uint32_t key_frames_processed,
                                           float p99_processing_time_ms)
    : VideoStats(/*timestamp=*/0.0,
                 frames_processed,
                 key_frames_processed,
                 p99_processing_time_ms) {}

WebrtcVideoStatsDB::VideoStats::VideoStats(const VideoStats& entry) = default;

WebrtcVideoStatsDB::VideoStats& WebrtcVideoStatsDB::VideoStats::operator=(
    const VideoStats& entry) = default;

std::string WebrtcVideoStatsDB::VideoStats::ToLogString() const {
  return base::StringPrintf(
      "VideoStats {Frames processed:%u, key frames processed:%u, p99 "
      "processing time:%.2f}",
      frames_processed, key_frames_processed, p99_processing_time_ms);
}

bool operator==(const WebrtcVideoStatsDB::VideoDescKey& x,
                const WebrtcVideoStatsDB::VideoDescKey& y) {
  return x.is_decode_stats == y.is_decode_stats &&
         x.codec_profile == y.codec_profile &&
         x.hardware_accelerated == y.hardware_accelerated &&
         x.pixels == y.pixels;
}
bool operator!=(const WebrtcVideoStatsDB::VideoDescKey& x,
                const WebrtcVideoStatsDB::VideoDescKey& y) {
  return !(x == y);
}

bool operator==(const WebrtcVideoStatsDB::VideoStats& x,
                const WebrtcVideoStatsDB::VideoStats& y) {
  return x.timestamp == y.timestamp &&
         x.frames_processed == y.frames_processed &&
         x.key_frames_processed == y.key_frames_processed &&
         x.p99_processing_time_ms == y.p99_processing_time_ms;
}
bool operator!=(const WebrtcVideoStatsDB::VideoStats& x,
                const WebrtcVideoStatsDB::VideoStats& y) {
  return !(x == y);
}

// static
base::TimeDelta WebrtcVideoStatsDB::GetMaxTimeToKeepStats() {
  return base::Days(base::GetFieldTrialParamByFeatureAsInt(
      kWebrtcMediaCapabilitiesParameters, kMaxDaysToKeepStatsParamName,
      kMaxDaysToKeepStatsDefault));
}

// static
int WebrtcVideoStatsDB::GetMaxEntriesPerConfig() {
  return base::GetFieldTrialParamByFeatureAsInt(
      kWebrtcMediaCapabilitiesParameters, kMaxEntriesPerConfigParamName,
      kMaxEntriesPerConfigDefault);
}

}  // namespace media