1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef FRAME_DROPPER_H_
18 
19 #define FRAME_DROPPER_H_
20 
21 #include <utils/Errors.h>
22 #include <utils/RefBase.h>
23 
24 #include <media/stagefright/foundation/ABase.h>
25 
26 namespace android {
27 
28 struct FrameDropper : public RefBase {
29     // No frames will be dropped until a valid max frame rate is set.
30     FrameDropper();
31 
32     // maxFrameRate required to be positive.
33     status_t setMaxFrameRate(float maxFrameRate);
34 
35     // Returns false if max frame rate has not been set via setMaxFrameRate.
36     bool shouldDrop(int64_t timeUs);
37 
38     // Returns true if all frame drop logic should be disabled.
disabledFrameDropper39     bool disabled() { return (mMinIntervalUs == -1ll); }
40 
41 protected:
42     virtual ~FrameDropper();
43 
44 private:
45     int64_t mDesiredMinTimeUs;
46     int64_t mMinIntervalUs;
47 
48     DISALLOW_EVIL_CONSTRUCTORS(FrameDropper);
49 };
50 
51 }  // namespace android
52 
53 #endif  // FRAME_DROPPER_H_
54