avc_utils.h revision 4dbff11975e737482537e1636051690188f3fbc4 
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
24namespace android {
25
26class ABitReader;
27
28enum {
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
39struct NALPosition {
40    size_t nalOffset;
41    size_t nalSize;
42};
43
44// Optionally returns sample aspect ratio as well.
45void 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.
52unsigned 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.
56signed 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|.
61unsigned 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|.
66signed parseSEWithFallback(ABitReader *br, signed fallback);
67
68// Skips an unsigned exp-golomb (ue) value from bit reader |br|.
69inline void skipUE(ABitReader *br) {
70    (void)parseUEWithFallback(br, 0U);
71}
72
73// Skips a signed exp-golomb (se) value from bit reader |br|.
74inline void skipSE(ABitReader *br) {
75    (void)parseSEWithFallback(br, 0);
76}
77
78status_t getNextNALUnit(
79        const uint8_t **_data, size_t *_size,
80        const uint8_t **nalStart, size_t *nalSize,
81        bool startCodeFollows = false);
82
83class MetaData;
84sp<MetaData> MakeAVCCodecSpecificData(const sp<ABuffer> &accessUnit);
85
86bool IsIDR(const sp<ABuffer> &accessUnit);
87bool IsAVCReferenceFrame(const sp<ABuffer> &accessUnit);
88uint32_t FindAVCLayerId(const uint8_t *data, size_t size);
89
90const char *AVCProfileToString(uint8_t profile);
91
92sp<MetaData> MakeAACCodecSpecificData(
93        unsigned profile, unsigned sampling_freq_index,
94        unsigned channel_configuration);
95
96// Given an MPEG4 video VOL-header chunk (starting with 0x00 0x00 0x01 0x2?)
97// parse it and fill in dimensions, returns true iff successful.
98bool ExtractDimensionsFromVOLHeader(
99        const uint8_t *data, size_t size, int32_t *width, int32_t *height);
100
101bool GetMPEGAudioFrameSize(
102        uint32_t header, size_t *frame_size,
103        int *out_sampling_rate = NULL, int *out_channels = NULL,
104        int *out_bitrate = NULL, int *out_num_samples = NULL);
105
106}  // namespace android
107
108#endif  // AVC_UTILS_H_
109