1 /*
2 * Copyright (C) 2010 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 AVC_UTILS_H_
18
19 #define AVC_UTILS_H_
20
21 #include <media/stagefright/foundation/ABuffer.h>
22 #include <utils/Errors.h>
23
24 namespace android {
25
26 class ABitReader;
27
28 enum {
29 kAVCProfileBaseline = 0x42,
30 kAVCProfileMain = 0x4d,
31 kAVCProfileExtended = 0x58,
32 kAVCProfileHigh = 0x64,
33 kAVCProfileHigh10 = 0x6e,
34 kAVCProfileHigh422 = 0x7a,
35 kAVCProfileHigh444 = 0xf4,
36 kAVCProfileCAVLC444Intra = 0x2c
37 };
38
39 struct NALPosition {
40 uint32_t nalOffset;
41 uint32_t nalSize;
42 };
43
44 // Optionally returns sample aspect ratio as well.
45 void FindAVCDimensions(
46 const sp<ABuffer> &seqParamSet,
47 int32_t *width, int32_t *height,
48 int32_t *sarWidth = NULL, int32_t *sarHeight = NULL);
49
50 // Gets and returns an unsigned exp-golomb (ue) value from a bit reader |br|. Aborts if the value
51 // is more than 64 bits long (>=0xFFFF (!)) or the bit reader overflows.
52 unsigned parseUE(ABitReader *br);
53
54 // Gets and returns a signed exp-golomb (se) value from a bit reader |br|. Aborts if the value is
55 // more than 64 bits long (>0x7FFF || <-0x7FFF (!)) or the bit reader overflows.
56 signed parseSE(ABitReader *br);
57
58 // Gets an unsigned exp-golomb (ue) value from a bit reader |br|, and returns it if it was
59 // successful. Returns |fallback| if it was unsuccessful. Note: if the value was longer that 64
60 // bits, it reads past the value and still returns |fallback|.
61 unsigned parseUEWithFallback(ABitReader *br, unsigned fallback);
62
63 // Gets a signed exp-golomb (se) value from a bit reader |br|, and returns it if it was successful.
64 // Returns |fallback| if it was unsuccessful. Note: if the value was longer that 64 bits, it reads
65 // past the value and still returns |fallback|.
66 signed parseSEWithFallback(ABitReader *br, signed fallback);
67
68 // Skips an unsigned exp-golomb (ue) value from bit reader |br|.
skipUE(ABitReader * br)69 inline void skipUE(ABitReader *br) {
70 (void)parseUEWithFallback(br, 0U);
71 }
72
73 // Skips a signed exp-golomb (se) value from bit reader |br|.
skipSE(ABitReader * br)74 inline void skipSE(ABitReader *br) {
75 (void)parseSEWithFallback(br, 0);
76 }
77
78 status_t getNextNALUnit(
79 const uint8_t **_data, size_t *_size,
80 const uint8_t **nalStart, size_t *nalSize,
81 bool startCodeFollows = false);
82
83 sp<ABuffer> MakeAVCCodecSpecificData(
84 const sp<ABuffer> &accessUnit, int32_t *width, int32_t *height,
85 int32_t *sarWidth = nullptr, int32_t *sarHeight = nullptr);
86
87 bool IsIDR(const uint8_t *data, size_t size);
88 bool IsAVCReferenceFrame(const sp<ABuffer> &accessUnit);
89 uint32_t FindAVCLayerId(const uint8_t *data, size_t size);
90
91 const char *AVCProfileToString(uint8_t profile);
92
93 // Given an MPEG4 video VOL-header chunk (starting with 0x00 0x00 0x01 0x2?)
94 // parse it and fill in dimensions, returns true iff successful.
95 bool ExtractDimensionsFromVOLHeader(
96 const uint8_t *data, size_t size, int32_t *width, int32_t *height);
97
98 bool GetMPEGAudioFrameSize(
99 uint32_t header, size_t *frame_size,
100 int *out_sampling_rate = NULL, int *out_channels = NULL,
101 int *out_bitrate = NULL, int *out_num_samples = NULL);
102
103 } // namespace android
104
105 #endif // AVC_UTILS_H_
106