1 /*
2 * Copyright (c) 2023 Shenzhen Kaihong Digital Industry Development Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 #include "adts.h"
17 #include "common/common_macro.h"
18
19 namespace OHOS {
20 namespace Sharing {
21
DumpAdtsHeader(const AdtsHeader & hed,uint8_t * out,size_t outSize)22 void AdtsHeader::DumpAdtsHeader(const AdtsHeader &hed, uint8_t *out, size_t outSize)
23 {
24 RETURN_IF_NULL(out);
25 if (outSize < ADTS_HEADER_LEN) {
26 return;
27 }
28 out[0] = ((hed.syncword_ >> 4) & 0xFF); // 8bit, 4:byte offset
29 out[1] = ((hed.syncword_ << 4) & 0xF0); // 4 bit, 4:byte offset
30 out[1] |= ((hed.id_ << 3) & 0x08); // 1 bit, 3:byte offset
31 out[1] |= ((hed.layer_ << 1) & 0x06); // 2bit
32 out[1] |= ((hed.protectionAbsent_) & 0x01); // 1 bit
33 out[2] = ((hed.profile_ << 6) & 0xC0); // 2 bit, 6:byte offset, 2:byte offset
34 out[2] |= ((hed.sfIndex_ << 2) & 0x3C); // 4bit, 2:byte offset
35 out[2] |= ((hed.privateBit_ << 1) & 0x02); // 1 bit, 2:byte offset
36 out[2] |= ((hed.channelConfiguration_ >> 2) & 0x03); // 1 bit, 2:byte offset
37 out[3] = ((hed.channelConfiguration_ << 6) & 0xC0); // 2 bit, 6:byte offset, 3:byte offset
38 out[3] |= ((hed.original_ << 5) & 0x20); // 1 bit, 5:byte offset, 3:byte offset
39 out[3] |= ((hed.home_ << 4) & 0x10); // 1 bit, 4:byte offset, 3:byte offset
40 out[3] |= ((hed.copyrightIdentificationBit_ << 3) & 0x08); // 1 bit, 3:byte offset
41 out[3] |= ((hed.copyrightIdentificationStart_ << 2) & 0x04); // 1 bit, 2:byte offset, 3:byte offset
42 out[3] |= ((hed.aacFrameLength_ >> 11) & 0x03); // 2 bit, 11:byte offset, 3:byte offset
43 out[4] = ((hed.aacFrameLength_ >> 3) & 0xFF); // 8 bit, 3:byte offset, 4:byte offset
44 out[5] = ((hed.aacFrameLength_ << 5) & 0xE0); // 3 bit, 5:byte offset
45 out[5] |= ((hed.adtsBufferFullness_ >> 6) & 0x1F); // 5 bit, 6:byte offset, 5:byte offset
46 out[6] = ((hed.adtsBufferFullness_ << 2) & 0xFC); // 6 bit, 2:byte offset, 6:byte offset
47 out[6] |= (hed.numberOfRawDataBlocksInFrame_ & 0x03); // 2 bit, 6:byte offset
48 }
49
ParseAacConfig(const std::string & config,AdtsHeader & adts)50 void AdtsHeader::ParseAacConfig(const std::string &config, AdtsHeader &adts)
51 {
52 uint8_t cfg1 = config[0];
53 uint8_t cfg2 = config[1];
54
55 int32_t audioObjectType;
56 int32_t samplingFrequencyIndex;
57 int32_t channelConfiguration;
58
59 audioObjectType = cfg1 >> 3; // 3:byte offset
60 samplingFrequencyIndex = ((cfg1 & 0x07) << 1) | (cfg2 >> 7); // 7:byte offset
61 channelConfiguration = (cfg2 & 0x7F) >> 3; // 3:byte offset
62
63 adts.syncword_ = 0x0FFF;
64 adts.id_ = 0;
65 adts.layer_ = 0;
66 adts.protectionAbsent_ = 1;
67 adts.profile_ = (uint32_t)(audioObjectType - 1);
68 adts.sfIndex_ = (uint32_t)samplingFrequencyIndex;
69 adts.privateBit_ = 0;
70 adts.channelConfiguration_ = (uint32_t)channelConfiguration;
71 adts.original_ = 0;
72 adts.home_ = 0;
73 adts.copyrightIdentificationBit_ = 0;
74 adts.copyrightIdentificationStart_ = 0;
75 adts.aacFrameLength_ = 7; // 7:aac header length
76 adts.adtsBufferFullness_ = 2047; // 2047:aac fixed value
77 adts.numberOfRawDataBlocksInFrame_ = 0;
78 }
79
DumpAacConfig(const std::string & config,size_t length,uint8_t * out,size_t outSize)80 int32_t AdtsHeader::DumpAacConfig(const std::string &config, size_t length, uint8_t *out, size_t outSize)
81 {
82 RETURN_INVALID_IF_NULL(out);
83 AdtsHeader header;
84 ParseAacConfig(config, header);
85 header.aacFrameLength_ = (decltype(header.aacFrameLength_))(ADTS_HEADER_LEN + length);
86 DumpAdtsHeader(header, out, outSize);
87 return ADTS_HEADER_LEN;
88 }
89
GetAacFrameLength(const uint8_t * data,size_t bytes)90 int32_t AdtsHeader::GetAacFrameLength(const uint8_t *data, size_t bytes)
91 {
92 RETURN_INVALID_IF_NULL(data);
93 uint16_t len;
94 if (bytes < 7) // 7:aac header length
95 return -1;
96 if (0xFF != data[0] || 0xF0 != (data[1] & 0xF0)) {
97 return -1;
98 }
99 len = ((uint16_t)(data[3] & 0x03) << 11) | // 3:byte offset, 11:byte length
100 ((uint16_t)data[4] << 3) | // 4:byte offset, 3:byte length
101 ((uint16_t)(data[5] >> 5) & 0x07); // 5:byte offset, 7:byte length
102 return len;
103 }
104 } // namespace Sharing
105 } // namespace OHOS