1 /*
2  * Copyright 2021 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 #pragma once
18 
19 #include <memory>
20 
21 #include "phash_config.h"
22 
23 namespace android {
24 
25 // Class that generates a perceptual hash of an ImageFrame.
26 // Not thread-safe.
27 class PhashFingerprinter {
28 public:
29     // Produce the fingerprint of an image frame, which must be 32 by 32
30     // grayscale of 1 byte per pixel.
31     int64_t GenerateFingerprint(const uint8_t* frame);
32 
33 private:
34     // Buffers to avoid memory allocation:
35     int16_t dct_buf_[kImageSize];
36 };
37 } // namespace android
38