如何使用 AVFoundation 合并 1 个视频和 2 个或更多音频文件
How to merge 1 video and 2 or more audio files with AVFoundation
我正在尝试通过合并 1 个“.mov”文件和 2 个或更多“.caf”文件来创建视频，我的代码在合并 1 个“.mov”文件和 1 个“.caf”文件时工作正常，并且在将它与更多“.caf”文件合并时它不会崩溃也不会抛出任何错误，但是，在后一种情况下，唯一可以听到的音频是第一个。
我尝试过在不同时间添加音频，同时添加2个，但结果是一样的，只有1个音频。
如果我尝试合并视频的音频，同样的事情会发生，只能听到第一个音频（视频的音频）。
这是我的代码：
public void mergeAudios()
{
//This funtion merges the final video with the new audio
//microphone
AVCaptureDevice microphone = AVCaptureDevice.DefaultDeviceWithMediaType(AVMediaType.Audio);
AVMutableComposition mixComposition = new AVMutableComposition();
#region HoldVideoTrack
AVAsset video_asset = AVAsset.FromUrl(NSUrl.FromFilename(FinalVideo));
CMTimeRange range;
range = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = video_asset.Duration
};
AVMutableCompositionTrack videoTrack = mixComposition.AddMutableTrack(AVMediaType.Video, 0);
AVAssetTrack assetVideoTrack = video_asset.TracksWithMediaType(AVMediaType.Video)[0];
videoTrack.InsertTimeRange(range, assetVideoTrack, mixComposition.Duration, out NSError error1);
try
{
CMTime prevDur = CMTime.Zero;
foreach (Audio _audio in TTS_list)
{
AVAsset audio_asset = AVAsset.FromUrl(NSUrl.FromFilename(_audio.Path));
CMTime aaa = new CMTime((long)(_audio.Starting_Point * Convert.ToDouble(mixComposition.Duration.TimeScale)), mixComposition.Duration.TimeScale);
AVMutableCompositionTrack audioTrack = mixComposition.AddMutableTrack(AVMediaType.Audio, 0);
AVAssetTrack assetAudioTrack = audio_asset.TracksWithMediaType(AVMediaType.Audio)[0];
audioTrack.InsertTimeRange(_audio.Range, assetAudioTrack, prevDur /*aaa*/, out NSError error3);
prevDur += _audio.Range.Duration;
}
}
catch (Exception error) { }
#endregion
#region Instructions
AVMutableVideoCompositionLayerInstruction[] Instruction_Array = new AVMutableVideoCompositionLayerInstruction[1];
Instruction_Array[0] = SetInstruction(video_asset, mixComposition.Duration, videoTrack);
#endregion
// 6
var mainInstruction = new AVMutableVideoCompositionInstruction();
CMTimeRange rangeIns = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = mixComposition.Duration
};
mainInstruction.BackgroundColor = UIColor.FromRGBA(0.63f, 0.84f, 0.82f, 1.000f).CGColor;
mainInstruction.TimeRange = rangeIns;
mainInstruction.LayerInstructions = Instruction_Array;
var mainComposition = new AVMutableVideoComposition()
{
Instructions = new AVVideoCompositionInstruction[1] { mainInstruction },
FrameDuration = new CMTime(1, 30),
RenderSize = new CoreGraphics.CGSize(UIScreenWidth, UIScreenHeight)
};
//... export video ...
pathh = NSUrl.FromFilename(Path.Combine(Path.GetTempPath(), "temporaryClip/Whole2.mov"));
AVAssetExportSession exportSession = new AVAssetExportSession(mixComposition, AVAssetExportSessionPreset.MediumQuality)
{
OutputUrl = NSUrl.FromFilename(Path.Combine(Path.GetTempPath(), "temporaryClip/Whole2.mov")),
OutputFileType = AVFileType.QuickTimeMovie,
ShouldOptimizeForNetworkUse = true,
VideoComposition = mainComposition
};
exportSession.ExportAsynchronously(_OnExportDone);
}
如果您需要更多信息，我会在看到您的请求后立即提供。谢谢大家的宝贵时间，祝你有美好的一天。
好的，我刚刚找到问题所在；基本上，在使用 AVMutableComposition 时必须遵循一条黄金法则（至少要合并多个音频），即：
1 audio = 1 video + 1 instruction
换句话说，对于每个音频，必须有 1 个视频和 1 个说明。遵循这条规则，我之前的代码结果如下：
public void mergeAudios()
{
//This funtion merges the final video with the new audio
#region HoldVideoTrack
AVAsset video_asset = AVAsset.FromUrl(NSUrl.FromFilename(FinalVideo));
//This range applies to the video, not to the mixcomposition
CMTimeRange range = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = video_asset.Duration
};
#endregion
AVMutableComposition mixComposition = new AVMutableComposition();
#region AddsVideo
AVMutableCompositionTrack videoTrack = mixComposition.AddMutableTrack(AVMediaType.Video, 0);
AVAssetTrack assetVideoTrack = video_asset.TracksWithMediaType(AVMediaType.Video)[0];
videoTrack.InsertTimeRange(range, assetVideoTrack, CMTime.Zero, out NSError error1);
#endregion
#region AddsVideo'sAudio
//If the device can't use the microphone then the original video's audio will not exist
AVCaptureDevice microphone = AVCaptureDevice.DefaultDeviceWithMediaType(AVMediaType.Audio);
if (microphone != null)
{
AVMutableCompositionTrack audio_video_Track = mixComposition.AddMutableTrack(AVMediaType.Audio, 0);
AVAssetTrack assetAudioVideoTrack = video_asset.TracksWithMediaType(AVMediaType.Audio)[0];
audio_video_Track.InsertTimeRange(range, assetAudioVideoTrack, mixComposition.Duration, out NSError error2);
}
#endregion
//[TTS_list.Count + 1]; +1 = original Video
AVMutableVideoCompositionLayerInstruction[] Instruction_Array = new AVMutableVideoCompositionLayerInstruction[TTS_list.Count + 1];
//This instruction is for "FinalVideo"
Instruction_Array[0] = SetInstruction(video_asset, mixComposition.Duration, videoTrack);
#region TestingEnviroment
//We will use counter to specify the position in Instruction_Array, we start with 1 because we have already added 1 instruction for "FinalVideo"
int counter = 1;
foreach(Audio _audioo in TTS_list)
{
#region Video
AVMutableCompositionTrack videoTrack_forAudio = mixComposition.AddMutableTrack(AVMediaType.Video, 0);
AVAssetTrack assetVideoTrack_forAudio = video_asset.TracksWithMediaType(AVMediaType.Video)[0];
//This range applies to the video, not to the mixcomposition, making its duration 0 and having no overall effect on the final video.
//We have to declare 1 video for each audio in order to merge multiple audios. Doing it this way the videos have no effect, but the audios do
CMTimeRange range0 = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = CMTime.FromSeconds(0, 600)
};
videoTrack_forAudio.InsertTimeRange(range0, assetVideoTrack_forAudio, mixComposition.Duration, out NSError error4);
#endregion
#region Audio
AVAsset audio_asset = AVAsset.FromUrl(NSUrl.FromFilename(_audioo.Path));
//This range applies to the video, not to the mixcomposition
//We use _audio.Duration instead of audio_asset.Duration.Seconds because the audio's duration might be trimmed
CMTimeRange audio_CMTime = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = CMTime.FromSeconds(_audioo.Duration, 600)
};
//This range applies to mixcomposition, not to the video
var starting_CMTime = CMTime.FromSeconds(_audioo.Starting_Point, 600);
AVMutableCompositionTrack audioTrack = mixComposition.AddMutableTrack(AVMediaType.Audio, 0);
AVAssetTrack assetAudioTrack = audio_asset.TracksWithMediaType(AVMediaType.Audio)[0];
audioTrack.InsertTimeRange(audio_CMTime, assetAudioTrack, starting_CMTime, out NSError error5);
#endregion
#region Instruction
Instruction_Array[counter] = SetInstruction(video_asset, mixComposition.Duration, videoTrack);
counter += 1;
#endregion
}
#endregion
#region Instructions
var mainInstruction = new AVMutableVideoCompositionInstruction();
CMTimeRange rangeIns = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = mixComposition.Duration
};
mainInstruction.BackgroundColor = UIColor.FromRGBA(0.63f, 0.84f, 0.82f, 1.000f).CGColor;
mainInstruction.TimeRange = rangeIns;
mainInstruction.LayerInstructions = Instruction_Array;
#endregion
var mainComposition = new AVMutableVideoComposition()
{
Instructions = new AVVideoCompositionInstruction[1] { mainInstruction },
FrameDuration = new CMTime(1, 30),
RenderSize = new CoreGraphics.CGSize(UIScreenWidth, UIScreenHeight)
};
finalVideo_path = NSUrl.FromFilename(Path.Combine(Path.GetTempPath(), "temporaryClip/FinalVideoEdit.mov"));
if (File.Exists(Path.GetTempPath() + "temporaryClip/FinalVideoEdit.mov"))
{
File.Delete(Path.GetTempPath() + "temporaryClip/FinalVideoEdit.mov");
}
AVAssetExportSession exportSession = new AVAssetExportSession(mixComposition, AVAssetExportSessionPreset.MediumQuality)
{
OutputUrl = finalVideo_path,
OutputFileType = AVFileType.QuickTimeMovie,
ShouldOptimizeForNetworkUse = true,
VideoComposition = mainComposition
};
exportSession.ExportAsynchronously(_OnExportDone);
}
我正在尝试通过合并 1 个“.mov”文件和 2 个或更多“.caf”文件来创建视频，我的代码在合并 1 个“.mov”文件和 1 个“.caf”文件时工作正常，并且在将它与更多“.caf”文件合并时它不会崩溃也不会抛出任何错误，但是，在后一种情况下，唯一可以听到的音频是第一个。 我尝试过在不同时间添加音频，同时添加2个，但结果是一样的，只有1个音频。
如果我尝试合并视频的音频，同样的事情会发生，只能听到第一个音频（视频的音频）。
这是我的代码：
public void mergeAudios()
{
//This funtion merges the final video with the new audio
//microphone
AVCaptureDevice microphone = AVCaptureDevice.DefaultDeviceWithMediaType(AVMediaType.Audio);
AVMutableComposition mixComposition = new AVMutableComposition();
#region HoldVideoTrack
AVAsset video_asset = AVAsset.FromUrl(NSUrl.FromFilename(FinalVideo));
CMTimeRange range;
range = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = video_asset.Duration
};
AVMutableCompositionTrack videoTrack = mixComposition.AddMutableTrack(AVMediaType.Video, 0);
AVAssetTrack assetVideoTrack = video_asset.TracksWithMediaType(AVMediaType.Video)[0];
videoTrack.InsertTimeRange(range, assetVideoTrack, mixComposition.Duration, out NSError error1);
try
{
CMTime prevDur = CMTime.Zero;
foreach (Audio _audio in TTS_list)
{
AVAsset audio_asset = AVAsset.FromUrl(NSUrl.FromFilename(_audio.Path));
CMTime aaa = new CMTime((long)(_audio.Starting_Point * Convert.ToDouble(mixComposition.Duration.TimeScale)), mixComposition.Duration.TimeScale);
AVMutableCompositionTrack audioTrack = mixComposition.AddMutableTrack(AVMediaType.Audio, 0);
AVAssetTrack assetAudioTrack = audio_asset.TracksWithMediaType(AVMediaType.Audio)[0];
audioTrack.InsertTimeRange(_audio.Range, assetAudioTrack, prevDur /*aaa*/, out NSError error3);
prevDur += _audio.Range.Duration;
}
}
catch (Exception error) { }
#endregion
#region Instructions
AVMutableVideoCompositionLayerInstruction[] Instruction_Array = new AVMutableVideoCompositionLayerInstruction[1];
Instruction_Array[0] = SetInstruction(video_asset, mixComposition.Duration, videoTrack);
#endregion
// 6
var mainInstruction = new AVMutableVideoCompositionInstruction();
CMTimeRange rangeIns = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = mixComposition.Duration
};
mainInstruction.BackgroundColor = UIColor.FromRGBA(0.63f, 0.84f, 0.82f, 1.000f).CGColor;
mainInstruction.TimeRange = rangeIns;
mainInstruction.LayerInstructions = Instruction_Array;
var mainComposition = new AVMutableVideoComposition()
{
Instructions = new AVVideoCompositionInstruction[1] { mainInstruction },
FrameDuration = new CMTime(1, 30),
RenderSize = new CoreGraphics.CGSize(UIScreenWidth, UIScreenHeight)
};
//... export video ...
pathh = NSUrl.FromFilename(Path.Combine(Path.GetTempPath(), "temporaryClip/Whole2.mov"));
AVAssetExportSession exportSession = new AVAssetExportSession(mixComposition, AVAssetExportSessionPreset.MediumQuality)
{
OutputUrl = NSUrl.FromFilename(Path.Combine(Path.GetTempPath(), "temporaryClip/Whole2.mov")),
OutputFileType = AVFileType.QuickTimeMovie,
ShouldOptimizeForNetworkUse = true,
VideoComposition = mainComposition
};
exportSession.ExportAsynchronously(_OnExportDone);
}
如果您需要更多信息，我会在看到您的请求后立即提供。谢谢大家的宝贵时间，祝你有美好的一天。
好的，我刚刚找到问题所在；基本上，在使用 AVMutableComposition 时必须遵循一条黄金法则（至少要合并多个音频），即：
1 audio = 1 video + 1 instruction
换句话说，对于每个音频，必须有 1 个视频和 1 个说明。遵循这条规则，我之前的代码结果如下：
public void mergeAudios()
{
//This funtion merges the final video with the new audio
#region HoldVideoTrack
AVAsset video_asset = AVAsset.FromUrl(NSUrl.FromFilename(FinalVideo));
//This range applies to the video, not to the mixcomposition
CMTimeRange range = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = video_asset.Duration
};
#endregion
AVMutableComposition mixComposition = new AVMutableComposition();
#region AddsVideo
AVMutableCompositionTrack videoTrack = mixComposition.AddMutableTrack(AVMediaType.Video, 0);
AVAssetTrack assetVideoTrack = video_asset.TracksWithMediaType(AVMediaType.Video)[0];
videoTrack.InsertTimeRange(range, assetVideoTrack, CMTime.Zero, out NSError error1);
#endregion
#region AddsVideo'sAudio
//If the device can't use the microphone then the original video's audio will not exist
AVCaptureDevice microphone = AVCaptureDevice.DefaultDeviceWithMediaType(AVMediaType.Audio);
if (microphone != null)
{
AVMutableCompositionTrack audio_video_Track = mixComposition.AddMutableTrack(AVMediaType.Audio, 0);
AVAssetTrack assetAudioVideoTrack = video_asset.TracksWithMediaType(AVMediaType.Audio)[0];
audio_video_Track.InsertTimeRange(range, assetAudioVideoTrack, mixComposition.Duration, out NSError error2);
}
#endregion
//[TTS_list.Count + 1]; +1 = original Video
AVMutableVideoCompositionLayerInstruction[] Instruction_Array = new AVMutableVideoCompositionLayerInstruction[TTS_list.Count + 1];
//This instruction is for "FinalVideo"
Instruction_Array[0] = SetInstruction(video_asset, mixComposition.Duration, videoTrack);
#region TestingEnviroment
//We will use counter to specify the position in Instruction_Array, we start with 1 because we have already added 1 instruction for "FinalVideo"
int counter = 1;
foreach(Audio _audioo in TTS_list)
{
#region Video
AVMutableCompositionTrack videoTrack_forAudio = mixComposition.AddMutableTrack(AVMediaType.Video, 0);
AVAssetTrack assetVideoTrack_forAudio = video_asset.TracksWithMediaType(AVMediaType.Video)[0];
//This range applies to the video, not to the mixcomposition, making its duration 0 and having no overall effect on the final video.
//We have to declare 1 video for each audio in order to merge multiple audios. Doing it this way the videos have no effect, but the audios do
CMTimeRange range0 = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = CMTime.FromSeconds(0, 600)
};
videoTrack_forAudio.InsertTimeRange(range0, assetVideoTrack_forAudio, mixComposition.Duration, out NSError error4);
#endregion
#region Audio
AVAsset audio_asset = AVAsset.FromUrl(NSUrl.FromFilename(_audioo.Path));
//This range applies to the video, not to the mixcomposition
//We use _audio.Duration instead of audio_asset.Duration.Seconds because the audio's duration might be trimmed
CMTimeRange audio_CMTime = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = CMTime.FromSeconds(_audioo.Duration, 600)
};
//This range applies to mixcomposition, not to the video
var starting_CMTime = CMTime.FromSeconds(_audioo.Starting_Point, 600);
AVMutableCompositionTrack audioTrack = mixComposition.AddMutableTrack(AVMediaType.Audio, 0);
AVAssetTrack assetAudioTrack = audio_asset.TracksWithMediaType(AVMediaType.Audio)[0];
audioTrack.InsertTimeRange(audio_CMTime, assetAudioTrack, starting_CMTime, out NSError error5);
#endregion
#region Instruction
Instruction_Array[counter] = SetInstruction(video_asset, mixComposition.Duration, videoTrack);
counter += 1;
#endregion
}
#endregion
#region Instructions
var mainInstruction = new AVMutableVideoCompositionInstruction();
CMTimeRange rangeIns = new CMTimeRange()
{
Start = new CMTime(0, 0),
Duration = mixComposition.Duration
};
mainInstruction.BackgroundColor = UIColor.FromRGBA(0.63f, 0.84f, 0.82f, 1.000f).CGColor;
mainInstruction.TimeRange = rangeIns;
mainInstruction.LayerInstructions = Instruction_Array;
#endregion
var mainComposition = new AVMutableVideoComposition()
{
Instructions = new AVVideoCompositionInstruction[1] { mainInstruction },
FrameDuration = new CMTime(1, 30),
RenderSize = new CoreGraphics.CGSize(UIScreenWidth, UIScreenHeight)
};
finalVideo_path = NSUrl.FromFilename(Path.Combine(Path.GetTempPath(), "temporaryClip/FinalVideoEdit.mov"));
if (File.Exists(Path.GetTempPath() + "temporaryClip/FinalVideoEdit.mov"))
{
File.Delete(Path.GetTempPath() + "temporaryClip/FinalVideoEdit.mov");
}
AVAssetExportSession exportSession = new AVAssetExportSession(mixComposition, AVAssetExportSessionPreset.MediumQuality)
{
OutputUrl = finalVideo_path,
OutputFileType = AVFileType.QuickTimeMovie,
ShouldOptimizeForNetworkUse = true,
VideoComposition = mainComposition
};
exportSession.ExportAsynchronously(_OnExportDone);
}