HaishinKit.swift/Sources/MP4/MP4TrackRunBox.swift

74 lines
2.3 KiB
Swift

import Foundation
/// ISO/IEC 14496-12 5th 8.8.8.2
struct MP4TrackRunBox: MP4FullBox {
struct Sample {
var duration: UInt32?
var size: UInt32?
var flags: UInt32?
var compositionTimeOffset: Int32?
}
enum Field: UInt32 {
case dataOffset = 0x000001
case firstSampleFlags = 0x000004
case sampleDuration = 0x000100
case sampleSize = 0x000200
case sampleFlags = 0x000400
case sampleCompositionTimeOffset = 0x000800
}
// MARK: MP4FullBox
var size: UInt32 = 0
let type: String = "trun"
var offset: UInt64 = 0
var children: [MP4BoxConvertible] = []
var version: UInt8 = 0
var flags: UInt32 = 0
// MARK: MP4TrackRunBox
var dataOffset: Int32 = 0
var firstSampleFlags: UInt32 = 0
var samples: [Sample] = []
private func contains(_ value: Field) -> Bool {
return (flags & value.rawValue) != 0
}
}
extension MP4TrackRunBox: DataConvertible {
var data: Data {
get {
Data()
}
set {
do {
let buffer = ByteArray(data: newValue)
size = try buffer.readUInt32()
_ = try buffer.readBytes(4)
version = try buffer.readUInt8()
flags = try buffer.readUInt24()
let sampleCount: UInt32 = try buffer.readUInt32()
if contains(.dataOffset) {
dataOffset = try buffer.readInt32()
}
if contains(.firstSampleFlags) {
firstSampleFlags = try buffer.readUInt32()
}
samples.removeAll()
for _ in 0..<sampleCount {
samples.append(Sample(
duration: contains(.sampleDuration) ? try buffer.readUInt32() : nil,
size: contains(.sampleSize) ? try buffer.readUInt32() : nil,
flags: contains(.sampleFlags) ? try buffer.readUInt32() : nil,
compositionTimeOffset: contains(.sampleCompositionTimeOffset) ? try buffer.readInt32() : nil
))
}
} catch {
logger.error(error)
}
}
}
}
extension MP4Box.Names {
static let trun = MP4Box.Name<MP4TrackRunBox>(rawValue: "trun")
}