rhubarb-lip-sync/lib/webrtc-8d2248ff/webrtc/examples/objc/AppRTCDemo/ARDBitrateTracker.m

46 lines
1.3 KiB
Objective-C

/*
* Copyright 2015 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.
*/
#import "ARDBitrateTracker.h"
#import <QuartzCore/QuartzCore.h>
@implementation ARDBitrateTracker {
CFTimeInterval _prevTime;
NSInteger _prevByteCount;
}
@synthesize bitrate = _bitrate;
+ (NSString *)bitrateStringForBitrate:(double)bitrate {
if (bitrate > 1e6) {
return [NSString stringWithFormat:@"%.2fMbps", bitrate * 1e-6];
} else if (bitrate > 1e3) {
return [NSString stringWithFormat:@"%.0fKbps", bitrate * 1e-3];
} else {
return [NSString stringWithFormat:@"%.0fbps", bitrate];
}
}
- (NSString *)bitrateString {
return [[self class] bitrateStringForBitrate:_bitrate];
}
- (void)updateBitrateWithCurrentByteCount:(NSInteger)byteCount {
CFTimeInterval currentTime = CACurrentMediaTime();
if (_prevTime && (byteCount > _prevByteCount)) {
_bitrate = (byteCount - _prevByteCount) * 8 / (currentTime - _prevTime);
}
_prevByteCount = byteCount;
_prevTime = currentTime;
}
@end