-
Notifications
You must be signed in to change notification settings - Fork 2
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
* move c point to Data * refactroy large code to funcations
- Loading branch information
1 parent
ddc1442
commit 6a19182
Showing
5 changed files
with
180 additions
and
161 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,62 @@ | ||
// | ||
// AudioSpecificConfig.swift | ||
// | ||
// | ||
// Created by 郭 輝平 on 2023/09/12. | ||
// | ||
|
||
import Foundation | ||
import HPRTMP | ||
import AVFoundation | ||
|
||
/* | ||
AudioSpecificConfig = 2 bytes, | ||
number = bits | ||
------------------------------ | ||
| audioObjectType (5) | | ||
| sampleingFrequencyIndex (4)| | ||
| channelConfigration (4) | | ||
| frameLengthFlag (1) | | ||
| dependsOnCoreCoder (1) | | ||
| extensionFlag (1) | | ||
------------------------------ | ||
*/ | ||
struct AudioSpecificConfig { | ||
let objectType: MPEG4ObjectID | ||
var channelConfig: ChannelConfigType = .unknown | ||
var frequencyType: SampleFrequencyType = .unknown | ||
let frameLengthFlag: Bool | ||
let dependsOnCoreCoder: UInt8 | ||
let extensionFlag: UInt8 | ||
init (data: Data) { | ||
self.objectType = MPEG4ObjectID(rawValue: Int((0b11111000 & data[0]) >> 3)) ?? .aac_Main | ||
self.frequencyType = SampleFrequencyType(rawValue: (0b00000111 & data[0]) << 1 | (0b10000000 & data[1]) >> 7) | ||
self.channelConfig = ChannelConfigType(rawValue: (0b01111000 & data[1]) >> 3) | ||
let value = UInt8(data[1] & 0b00100000) == 1 | ||
self.frameLengthFlag = value | ||
self.dependsOnCoreCoder = data[1] & 0b000000010 | ||
self.extensionFlag = data[1] & 0b000000001 | ||
} | ||
|
||
init(objectType: MPEG4ObjectID, channelConfig: ChannelConfigType, frequencyType: SampleFrequencyType, frameLengthFlag: Bool = false, dependsOnCoreCoder: UInt8 = 0, extensionFlag: UInt8 = 0) { | ||
self.objectType = objectType | ||
self.channelConfig = channelConfig | ||
self.frequencyType = frequencyType | ||
self.frameLengthFlag = frameLengthFlag | ||
self.dependsOnCoreCoder = dependsOnCoreCoder | ||
self.extensionFlag = extensionFlag | ||
} | ||
|
||
var encodeData: Data { | ||
get { | ||
let flag = self.frameLengthFlag ? 1 : 0 | ||
let first = UInt8(self.objectType.rawValue) << 3 | UInt8(self.frequencyType.rawValue >> 1 & 0b00000111) | ||
let second = (0b10000000 & self.frequencyType.rawValue << 7) | | ||
(0b01111000 & self.channelConfig.rawValue << 3) | | ||
(UInt8(flag) << 2) | | ||
(self.dependsOnCoreCoder << 1) | | ||
self.extensionFlag | ||
return Data([first, second]) | ||
} | ||
} | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.