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Diffstat (limited to 'webrtc/modules/video_coding/codec_timer.cc')
-rw-r--r-- | webrtc/modules/video_coding/codec_timer.cc | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/webrtc/modules/video_coding/codec_timer.cc b/webrtc/modules/video_coding/codec_timer.cc new file mode 100644 index 0000000000..60add8fc4b --- /dev/null +++ b/webrtc/modules/video_coding/codec_timer.cc @@ -0,0 +1,96 @@ +/* + * Copyright (c) 2011 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. + */ + +#include "webrtc/modules/video_coding/codec_timer.h" + +#include <assert.h> + +namespace webrtc { + +// The first kIgnoredSampleCount samples will be ignored. +static const int32_t kIgnoredSampleCount = 5; + +VCMCodecTimer::VCMCodecTimer() + : _filteredMax(0), _ignoredSampleCount(0), _shortMax(0), _history() { + Reset(); +} + +void VCMCodecTimer::Reset() { + _filteredMax = 0; + _ignoredSampleCount = 0; + _shortMax = 0; + for (int i = 0; i < MAX_HISTORY_SIZE; i++) { + _history[i].shortMax = 0; + _history[i].timeMs = -1; + } +} + +// Update the max-value filter +void VCMCodecTimer::MaxFilter(int32_t decodeTime, int64_t nowMs) { + if (_ignoredSampleCount >= kIgnoredSampleCount) { + UpdateMaxHistory(decodeTime, nowMs); + ProcessHistory(nowMs); + } else { + _ignoredSampleCount++; + } +} + +void VCMCodecTimer::UpdateMaxHistory(int32_t decodeTime, int64_t now) { + if (_history[0].timeMs >= 0 && now - _history[0].timeMs < SHORT_FILTER_MS) { + if (decodeTime > _shortMax) { + _shortMax = decodeTime; + } + } else { + // Only add a new value to the history once a second + if (_history[0].timeMs == -1) { + // First, no shift + _shortMax = decodeTime; + } else { + // Shift + for (int i = (MAX_HISTORY_SIZE - 2); i >= 0; i--) { + _history[i + 1].shortMax = _history[i].shortMax; + _history[i + 1].timeMs = _history[i].timeMs; + } + } + if (_shortMax == 0) { + _shortMax = decodeTime; + } + + _history[0].shortMax = _shortMax; + _history[0].timeMs = now; + _shortMax = 0; + } +} + +void VCMCodecTimer::ProcessHistory(int64_t nowMs) { + _filteredMax = _shortMax; + if (_history[0].timeMs == -1) { + return; + } + for (int i = 0; i < MAX_HISTORY_SIZE; i++) { + if (_history[i].timeMs == -1) { + break; + } + if (nowMs - _history[i].timeMs > MAX_HISTORY_SIZE * SHORT_FILTER_MS) { + // This sample (and all samples after this) is too old + break; + } + if (_history[i].shortMax > _filteredMax) { + // This sample is the largest one this far into the history + _filteredMax = _history[i].shortMax; + } + } +} + +// Get the maximum observed time within a time window +int32_t VCMCodecTimer::RequiredDecodeTimeMs(FrameType /*frameType*/) const { + return _filteredMax; +} +} // namespace webrtc |