我有一个视频文件,是由第三方库生成的,它从远程摄像机录制视频。该API以4fps和352x288px的AVI格式生成视频文件。
我一直在尝试将此视频转换为iOS可播放的格式。我知道iOS只支持有限的视频格式,因此一直在尝试让任何东西都能工作。
我尝试使用以下内容,这是基于iOS Convert AVI to MP4 Format programatically的...
import UIKit
import AVFoundation
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
@IBAction func convert(_ sender: Any) {
makeItSo()
}
func makeItSo() {
guard let inputUrl = Bundle.main.url(forResource: "DVR8-4580V, Channel 7", withExtension: "avi") else {
print("Could not find video source")
return
}
let paths = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
let documentsDirectory = paths[0]
let filePath = URL(fileURLWithPath: documentsDirectory).appendingPathComponent("MyVideo.mp4").absoluteString
let outputURL = URL(fileURLWithPath: filePath)
print("OutputURL = \(outputURL)")
convertVideoToLowQuailty(withInputURL: inputUrl, outputURL: outputURL, handler: { exportSession in
guard let exportSession = exportSession else {
print("No export session")
return
}
print("exportSession.status = \(exportSession.status)")
if exportSession.status == .completed {
// Video conversation completed
print("Video converstion completed")
} else {
print("Error = \(exportSession.error)")
}
})
}
func convertVideoToLowQuailty(withInputURL inputURL: URL?, outputURL: URL?, handler: @escaping (AVAssetExportSession?) -> Void) {
if let anURL = outputURL {
try? FileManager.default.removeItem(at: anURL)
}
var asset: AVURLAsset? = nil
if let anURL = inputURL {
asset = AVURLAsset(url: anURL, options: nil)
}
var exportSession: AVAssetExportSession? = nil
if let anAsset = asset {
exportSession = AVAssetExportSession(asset: anAsset, presetName: AVAssetExportPresetPassthrough)
}
exportSession?.outputURL = outputURL
exportSession?.outputFileType = .mp4
exportSession?.exportAsynchronously(completionHandler: {
handler(exportSession)
})
}
}
而其他几个变体都失败了。上述代码会出现以下错误:
Error = Optional(Error Domain=AVFoundationErrorDomain Code=-11822 "Cannot Open" UserInfo={NSLocalizedFailureReason=This media format is not supported., NSLocalizedDescription=Cannot Open, NSUnderlyingError=0x283244bd0 {Error Domain=NSOSStatusErrorDomain Code=-16976 "(null)"}})
我认为要么是我没有为转换器提供正确的选项/建议,要么就是AVFoundation不支持这种类型的操作。
以下是由MediaInfo生成的信息。
General
Complete name : /Users/swhitehead/Downloads/DVR8-4580V, Channel 8.avi
Format : AVI
Format/Info : Audio Video Interleave
File size : 361 KiB
Duration : 28s 500ms
Overall bit rate : 104 Kbps
Video
ID : 0
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Baseline@L2
Format settings : 1 Ref Frames
Format settings, CABAC : No
Format settings, ReFrames : 1 frame
Format settings, GOP : M=1, N=4
Codec ID : H264
Duration : 28s 500ms
Bit rate : 101 Kbps
Width : 352 pixels
Height : 288 pixels
Display aspect ratio : 1.222
Frame rate : 4.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.249
Stream size : 351 KiB (97%)
问题
有没有办法将这种类型的视频文件转换为支持iOS播放的mp4格式?
注意:我知道这可能是一个广泛的问题,因为可能不存在简单的解决方案,但即使有一些建议或提示也会让我感激不尽,因为它让我感到很疯狂。