使用AVMutableCompositionTrack在AVMutableComposition中合并视频和图像,而不是AVVideoCompositionCoreAnimationTool?
问题描述:
以下代码使用AVMutableComposition
导出视频。但是在导出的视频中,如果要在源视频结束后显示图像3秒钟,是否有办法通过AVMutableCompositionTrack
来做到这一点,或者您需要添加图像图层并在视频结束后为其外观设置动画效果吗?使用AVMutableCompositionTrack在AVMutableComposition中合并视频和图像,而不是AVVideoCompositionCoreAnimationTool?
最终目标是将任意数量的图像和视频合并为一个主视频。
不幸的是,在测试过程中好像AVVideoCompositionCoreAnimationTool
严重减慢导出过程(从< 1秒10-20秒),因此我们的目标是避免AVVideoCompositionCoreAnimationTool
如果可能的话。
// Create composition object
let composition = AVMutableComposition()
let compositionVideoTrack = composition.addMutableTrackWithMediaType(AVMediaTypeVideo, preferredTrackID: CMPersistentTrackID(kCMPersistentTrackID_Invalid))
let compositionAudioTrack = composition.addMutableTrackWithMediaType(AVMediaTypeAudio, preferredTrackID: CMPersistentTrackID(kCMPersistentTrackID_Invalid))
var insertTime = kCMTimeZero
// Extract tracks from slice video
let videoURL = NSURL(fileURLWithPath: videoPath)
let videoAsset = AVURLAsset(URL: videoURL, options: nil)
let sourceVideoTrack = videoAsset.tracksWithMediaType(AVMediaTypeVideo)[0]
let sourceAudioTrack = videoAsset.tracksWithMediaType(AVMediaTypeAudio)[0]
do {
try compositionVideoTrack.insertTimeRange(CMTimeRangeMake(kCMTimeZero, videoAsset.duration), ofTrack: sourceVideoTrack, atTime: kCMTimeZero)
try compositionAudioTrack.insertTimeRange(CMTimeRangeMake(kCMTimeZero, videoAsset.duration), ofTrack: sourceAudioTrack, atTime: kCMTimeZero)
} catch {
print("Error with insertTimeRange while exporting video: \(error)")
}
// Export composition to video
let outputURL = getFilePath(getUniqueFilename(gMP4File))
let exporter = AVAssetExportSession(asset: composition, presetName: AVAssetExportPresetHighestQuality)
exporter!.outputURL = NSURL(fileURLWithPath: outputURL)
exporter!.outputFileType = AVFileTypeMPEG4
exporter!.exportAsynchronouslyWithCompletionHandler({
self.exportDidFinish(exporter!)
})
答
在咨询了其他人关于SO并进行更多网络研究后,似乎这是不可能的。将图像与视频合并为可从应用程序播放的主视频似乎需要AVVideoCompositionCoreAnimationTool。