void SetupAssetReaderWriterForAudio(AVAssetTrack audioTrack)
{
if (audioTrack == null)
{
return;
}
// Decompress to Linear PCM with the asset reader
// To read the media data from a specific asset track in the format in which it was stored, pass null to the settings parameter.
AVAssetReaderOutput output = AVAssetReaderTrackOutput.Create(audioTrack, (AudioSettings)null);
if (assetReader.CanAddOutput(output))
{
assetReader.AddOutput(output);
}
AVAssetWriterInput input = AVAssetWriterInput.Create(audioTrack.MediaType, (AudioSettings)null);
if (assetWriter.CanAddInput(input))
{
assetWriter.AddInput(input);
}
// Create and save an instance of ReadWriteSampleBufferChannel,
// which will coordinate the work of reading and writing sample buffers
audioSampleBufferChannel = new AudioChannel(output, input);
}
public bool SetupAssetWriterAudioInput(CMFormatDescription currentFormatDescription)
{
// If the AudioStreamBasicDescription is null return false;
if (!currentFormatDescription.AudioStreamBasicDescription.HasValue)
{
return(false);
}
var currentASBD = currentFormatDescription.AudioStreamBasicDescription.Value;
// Get the Audio Channel Layout from the Format Description.
var currentChannelLayout = currentFormatDescription.AudioChannelLayout;
var currentChannelLayoutData = currentChannelLayout == null ? new NSData() : currentChannelLayout.AsData();
NSDictionary audioCompressionSettings = NSDictionary.FromObjectsAndKeys(
new NSObject[]
{
NSNumber.FromInt32((int)AudioFormatType.MPEG4AAC),
NSNumber.FromDouble(currentASBD.SampleRate),
NSNumber.FromInt32(64000),
NSNumber.FromInt32(currentASBD.ChannelsPerFrame),
currentChannelLayoutData
},
new NSObject[]
{
AVAudioSettings.AVFormatIDKey,
AVAudioSettings.AVSampleRateKey,
AVAudioSettings.AVEncoderBitRateKey,
AVAudioSettings.AVNumberOfChannelsKey,
new NSString("AVChannelLayoutKey") //AVAudioSettings.AVChannelLayoutKey,
});
if (assetWriter.CanApplyOutputSettings(audioCompressionSettings, AVMediaType.Audio))
{
assetWriterAudioIn = new AVAssetWriterInput(AVMediaType.Audio, audioCompressionSettings);
assetWriterAudioIn.ExpectsMediaDataInRealTime = true;
if (assetWriter.CanAddInput(assetWriterAudioIn))
{
assetWriter.AddInput(assetWriterAudioIn);
}
else
{
Console.WriteLine("Couldn't add asset writer audio input.");
return(false);
}
}
else
{
Console.WriteLine("Couldn't apply audio output settings.");
return(false);
}
return(true);
}
public ReadWriteSampleBufferChannel (AVAssetReaderOutput readerOutput, AVAssetWriterInput writerInput)
{
if (readerOutput == null)
throw new ArgumentNullException ("readerOutput");
if (writerInput == null)
throw new ArgumentNullException ("writerInput");
this.readerOutput = readerOutput;
this.writerInput = writerInput;
serializationQueue = new DispatchQueue ("ReadWriteSampleBufferChannel queue");
}
public VideoChannel (AVAssetReaderOutput readerOutput, AVAssetWriterInput writerInput, IVideoTransformer transformer)
: base(readerOutput, writerInput)
{
if (transformer == null)
throw new ArgumentNullException ("transformer");
this.transformer = transformer;
var adaptorAttrs = new CVPixelBufferAttributes {
PixelFormatType = CVPixelFormatType.CV32BGRA
};
adaptor = new AVAssetWriterInputPixelBufferAdaptor (WriterInput, adaptorAttrs);
}
void SetupAssetReaserWriterForVideo(AVAssetTrack videoTrack)
{
if (videoTrack == null)
{
return;
}
// Decompress to ARGB with the asset reader
var decompSettings = new AVVideoSettingsUncompressed {
PixelFormatType = CVPixelFormatType.CV32BGRA,
AllocateWithIOSurface = null
};
AVAssetReaderOutput output = new AVAssetReaderTrackOutput(videoTrack, decompSettings);
assetReader.AddOutput(output);
// Get the format description of the track, to fill in attributes of the video stream that we don't want to change
var formatDescription = (CMVideoFormatDescription)videoTrack.FormatDescriptions.FirstOrDefault();
// Grab track dimensions from format description
CGSize trackDimensions = formatDescription != null
? formatDescription.GetPresentationDimensions(false, false)
: videoTrack.NaturalSize;
// Grab clean aperture, pixel aspect ratio from format description
AVVideoCodecSettings compressionSettings = null;
if (formatDescription != null)
{
var cleanApertureDescr = (NSDictionary)formatDescription.GetExtension(CVImageBuffer.CleanApertureKey);
var pixelAspectRatioDescr = (NSDictionary)formatDescription.GetExtension(CVImageBuffer.PixelAspectRatioKey);
compressionSettings = CreateCodecSettingsFor(cleanApertureDescr, pixelAspectRatioDescr);
}
// Compress to H.264 with the asset writer
var videoSettings = new AVVideoSettingsCompressed {
Codec = AVVideoCodec.H264,
Width = (int)trackDimensions.Width,
Height = (int)trackDimensions.Height,
CodecSettings = compressionSettings
};
AVAssetWriterInput input = new AVAssetWriterInput(videoTrack.MediaType, videoSettings);
input.Transform = videoTrack.PreferredTransform;
assetWriter.AddInput(input);
// Create and save an instance of ReadWriteSampleBufferChannel,
// which will coordinate the work of reading and writing sample buffers
videoSampleBufferChannel = new VideoChannel(output, input, transformer);
}
// HACK: Change CMFormatDescription to CMVideoFormatDescription
public bool SetupAssetWriterVideoInput(CMVideoFormatDescription currentFormatDescription)
{
//Console.WriteLine ("Setting up Video Asset Writer");
float bitsPerPixel;
// HACK: Change VideoDimensions to Dimensions, as this type was changed to CMVideoFormatDescription
var dimensions = currentFormatDescription.Dimensions;
int numPixels = dimensions.Width * dimensions.Height;
int bitsPerSecond;
// Assume that lower-than-SD resolution are intended for streaming, and use a lower bitrate
bitsPerPixel = numPixels < (640 * 480) ? 4.05F : 11.4F;
bitsPerSecond = (int)(numPixels * bitsPerPixel);
NSDictionary videoCompressionSettings = new NSDictionary(
AVVideo.CodecKey, AVVideo.CodecH264,
AVVideo.WidthKey, dimensions.Width,
AVVideo.HeightKey, dimensions.Height,
AVVideo.CompressionPropertiesKey, new NSDictionary(
AVVideo.AverageBitRateKey, bitsPerSecond,
AVVideo.MaxKeyFrameIntervalKey, 30
)
);
if (assetWriter.CanApplyOutputSettings(videoCompressionSettings, AVMediaType.Video))
{
// HACK: Change NSDictionary into AVVideoSettingsCompressed created using that NSDictionary (videoCompressionSettings)
assetWriterVideoIn = new AVAssetWriterInput(AVMediaType.Video, new AVVideoSettingsCompressed(videoCompressionSettings));
assetWriterVideoIn.ExpectsMediaDataInRealTime = true;
assetWriterVideoIn.Transform = TransformFromCurrentVideoOrientationToOrientation(ReferenceOrientation);
if (assetWriter.CanAddInput(assetWriterVideoIn))
{
assetWriter.AddInput(assetWriterVideoIn);
}
else
{
Console.WriteLine("Couldn't add asset writer video input.");
return(false);
}
}
else
{
Console.WriteLine("Couldn't apply video output settings.");
}
return(true);
}
public void StopRecording()
{
movieWritingQueue.DispatchAsync(() =>
{
if (recordingWillBeStopped || !IsRecording)
{
return;
}
recordingWillBeStopped = true;
// recordingDidStop is called from saveMovieToCameraRoll
RecordingWillStop?.Invoke();
if (assetWriter.FinishWriting())
{
if (assetWriterAudioIn != null)
{
assetWriterAudioIn.Dispose();
assetWriterAudioIn = null;
}
if (assetWriterVideoIn != null)
{
assetWriterVideoIn.Dispose();
assetWriterVideoIn = null;
}
lock (inUse)
{
assetWriter.Dispose();
assetWriter = null;
// Clear the 'Inuse' list when we're creating a new Recording session.
inUse.Clear();
}
readyToRecordVideo = false;
readyToRecordAudio = false;
SaveMovieToCameraRoll();
}
else
{
ShowError(assetWriter.Error);
}
});
}
public ReadWriteSampleBufferChannel(AVAssetReaderOutput readerOutput, AVAssetWriterInput writerInput)
{
if (readerOutput == null)
{
throw new ArgumentNullException("readerOutput");
}
if (writerInput == null)
{
throw new ArgumentNullException("writerInput");
}
this.readerOutput = readerOutput;
this.writerInput = writerInput;
serializationQueue = new DispatchQueue("ReadWriteSampleBufferChannel queue");
}
public VideoChannel(AVAssetReaderOutput readerOutput, AVAssetWriterInput writerInput, IVideoTransformer transformer)
: base(readerOutput, writerInput)
{
if (transformer == null)
{
throw new ArgumentNullException("transformer");
}
this.transformer = transformer;
var adaptorAttrs = new CVPixelBufferAttributes {
PixelFormatType = CVPixelFormatType.CV32BGRA
};
adaptor = new AVAssetWriterInputPixelBufferAdaptor(WriterInput, adaptorAttrs);
}
public ReadWriteSampleBufferChannel (AVAssetReaderOutput localAssetReaderOutput,
AVAssetWriterInput localAssetWriterInput,
bool useAdaptor)
{
_assetReaderOutput = localAssetReaderOutput;
_assetWriterInput = localAssetWriterInput;
_useAdaptor = useAdaptor;
if (_useAdaptor) {
var adaptorAttrs = new CVPixelBufferAttributes {
PixelFormatType = CVPixelFormatType.CV32BGRA
};
_adaptor = AVAssetWriterInputPixelBufferAdaptor.FromInput (localAssetWriterInput, adaptorAttrs.Dictionary);
}
_serializationQueue = new DispatchQueue ("ReadWriteSampleBufferChannel queue");
}
public bool SetupAssetWriterAudioInput(CMFormatDescription currentFormatDescription)
{
// If the AudioStreamBasicDescription is null return false;
if (!currentFormatDescription.AudioStreamBasicDescription.HasValue)
{
return(false);
}
var currentASBD = currentFormatDescription.AudioStreamBasicDescription.Value;
// Get the Audio Channel Layout from the Format Description.
var currentChannelLayout = currentFormatDescription.AudioChannelLayout;
var currentChannelLayoutData = currentChannelLayout == null ? new NSData() : currentChannelLayout.AsData();
NSDictionary audioCompressionSettings = new NSDictionary(
AVAudioSettings.AVFormatIDKey, AudioFormatType.MPEG4AAC,
AVAudioSettings.AVSampleRateKey, currentASBD.SampleRate,
AVAudioSettings.AVEncoderBitRateKey, 64000,
AVAudioSettings.AVNumberOfChannelsKey, currentASBD.ChannelsPerFrame,
AVAudioSettings.AVChannelLayoutKey, currentChannelLayoutData
);
if (assetWriter.CanApplyOutputSettings(audioCompressionSettings, AVMediaType.Audio))
{
// HACK: Change NSDictionary into AudioSettings created using that NSDictionary (audioCompressionSettings)
assetWriterAudioIn = new AVAssetWriterInput(AVMediaType.Audio, new AudioSettings(audioCompressionSettings));
assetWriterAudioIn.ExpectsMediaDataInRealTime = true;
if (assetWriter.CanAddInput(assetWriterAudioIn))
{
assetWriter.AddInput(assetWriterAudioIn);
}
else
{
Console.WriteLine("Couldn't add asset writer audio input.");
return(false);
}
}
else
{
Console.WriteLine("Couldn't apply audio output settings.");
return(false);
}
return(true);
}
public ReadWriteSampleBufferChannel(AVAssetReaderOutput localAssetReaderOutput,
AVAssetWriterInput localAssetWriterInput,
bool useAdaptor)
{
_assetReaderOutput = localAssetReaderOutput;
_assetWriterInput = localAssetWriterInput;
_useAdaptor = useAdaptor;
if (_useAdaptor)
{
var adaptorAttrs = new CVPixelBufferAttributes {
PixelFormatType = CVPixelFormatType.CV32BGRA
};
_adaptor = AVAssetWriterInputPixelBufferAdaptor.FromInput(localAssetWriterInput, adaptorAttrs.Dictionary);
}
_serializationQueue = new DispatchQueue("ReadWriteSampleBufferChannel queue");
}
private void SetupAssetReaderWriterForAudio(AVAssetTrack audioTrack)
{
if (audioTrack == null)
{
return;
}
// Decompress to Linear PCM with the asset reader
AVAssetReaderOutput output = AVAssetReaderTrackOutput.Create(audioTrack, (AudioSettings)null);
_assetReader.AddOutput(output);
AVAssetWriterInput input = AVAssetWriterInput.Create(audioTrack.MediaType, (AudioSettings)null);
_assetWriter.AddInput(input);
// Create and save an instance of AAPLRWSampleBufferChannel,
// which will coordinate the work of reading and writing sample buffers
_audioSampleBufferChannel = new ReadWriteSampleBufferChannel(output, input, false);
}
public bool SetupAssetWriterVideoInput(CMFormatDescription currentFormatDescription)
{
//Console.WriteLine ("Setting up Video Asset Writer");
float bitsPerPixel;
var dimensions = currentFormatDescription.VideoDimensions;
int numPixels = dimensions.Width * dimensions.Height;
int bitsPerSecond;
// Assume that lower-than-SD resolution are intended for streaming, and use a lower bitrate
bitsPerPixel = numPixels < (640 * 480) ? 4.05F : 11.4F;
bitsPerSecond = (int)(numPixels * bitsPerPixel);
NSDictionary videoCompressionSettings = NSDictionary.FromObjectsAndKeys(
new NSObject[]
{ // The Compression Settings Values
AVVideo.CodecH264,
NSNumber.FromInt32(dimensions.Width),
NSNumber.FromInt32(dimensions.Height),
NSDictionary.FromObjectsAndKeys(
new object[]
{ // Compression Property Values
NSNumber.FromInt32(bitsPerSecond),
NSNumber.FromInt32(30)
},
new object[]
{ // Compression Property Keys
AVVideo.AverageBitRateKey,
AVVideo.MaxKeyFrameIntervalKey
})
},
new NSObject[]
{ // The Compression Settings Keys
AVVideo.CodecKey,
AVVideo.WidthKey,
AVVideo.HeightKey,
AVVideo.CompressionPropertiesKey
}
);
if (assetWriter.CanApplyOutputSettings(videoCompressionSettings, AVMediaType.Video))
{
assetWriterVideoIn = new AVAssetWriterInput(AVMediaType.Video, videoCompressionSettings);
assetWriterVideoIn.ExpectsMediaDataInRealTime = true;
assetWriterVideoIn.Transform = TransformFromCurrentVideoOrientationToOrientation(ReferenceOrientation);
if (assetWriter.CanAddInput(assetWriterVideoIn))
{
assetWriter.AddInput(assetWriterVideoIn);
}
else
{
Console.WriteLine("Couldn't add asset writer video input.");
return(false);
}
}
else
{
Console.WriteLine("Couldn't apply video output settings.");
}
return(true);
}
public Compression CompressVideo(NSUrl source, NSUrl destination, bool isMinBitRateEnabled = true, VideoQuality quality = VideoQuality.high, bool keepOriginalResolution = false)
{
var frameCount = 0;
var compressionOperation = new Compression();
var videoAsset = new AVUrlAsset(source);
try
{
var videoTrack = videoAsset.Tracks.First(x => x.MediaType == AVMediaType.Video);
var bitrate = videoTrack.EstimatedDataRate;
// Check for a min video bitrate before compression
if (isMinBitRateEnabled && bitrate <= MIN_BITRATE)
{
var error = new Compression();
error.title = "The provided bitrate is smaller than what is needed for compression try to set isMinBitRateEnabled to false";
//TODO: ENVIAR ENVENTO DE ERRO
return(error);
}
var newBitrate = getBitrate(bitrate, quality);
// Handle new width and height values
var videoSize = videoTrack.NaturalSize;
var size = generateWidthAndHeight(videoSize.Width, videoSize.Height, keepOriginalResolution);
var newWidth = size.Width;
var newHeight = size.Height;
// Total Frames
var durationInSeconds = videoAsset.Duration.Seconds;
var frameRate = videoTrack.NominalFrameRate;
var totalFrames = Math.Ceiling(durationInSeconds * (double)(frameRate));
// Progress
var totalUnits = Convert.ToInt64(totalFrames);
//var progress = NSProgress(totalUnits);
// Setup video writer input
var videoWriterInput = new AVAssetWriterInput(AVMediaType.Video, getVideoWriterSettings(newBitrate, newWidth, newHeight));
videoWriterInput.ExpectsMediaDataInRealTime = true;
videoWriterInput.Transform = videoTrack.PreferredTransform;
NSError nSError;
var videoWriter = new AVAssetWriter(destination, AVFileType.QuickTimeMovie, out nSError);
videoWriter.AddInput(videoWriterInput);
var videoReaderSettings = new NSDictionary(
"PixelFormatType", new NSNumber(875704438)
);
var videoReaderOutput = new AVAssetReaderTrackOutput(videoTrack, videoReaderSettings);
AVAssetReader videoReader;
try
{
videoReader = new AVAssetReader(videoAsset, out nSError);
videoReader.AddOutput(videoReaderOutput);
}
catch
{
Console.WriteLine("video reader error: (error)");
//TODO - Chamar eventi de erro
}
//TODO: Verificar como passar parametro nil
var audioSettings = new AudioSettings()
{
//EncoderBitRate = 64000,
//Format = AudioToolbox.AudioFormatType.,
NumberChannels = 1,
//SampleRate = 44100
};
var audioWriterInput = new AVAssetWriterInput(AVMediaType.Audio, audioSettings);
audioWriterInput.ExpectsMediaDataInRealTime = false;
videoWriter.AddInput(audioWriterInput);
//setup audio reader
var audioTrack = videoAsset.Tracks.FirstOrDefault(x => x.MediaType == AVMediaType.Audio);
var audioReaderOutput = new AVAssetReaderTrackOutput(audioTrack, audioSettings);
var audioReader = new AVAssetReader(videoAsset, out nSError);
audioReader.AddOutput(audioReaderOutput);
videoWriter.StartWriting();
}
catch (Exception ex)
{
//TODO: Incluir tratamento de erro
return(new Compression());
}
return(new Compression());
}
public bool SetupAssetWriterVideoInput (CMFormatDescription currentFormatDescription)
{
//Console.WriteLine ("Setting up Video Asset Writer");
float bitsPerPixel;
var dimensions = currentFormatDescription.VideoDimensions;
int numPixels = dimensions.Width * dimensions.Height;
int bitsPerSecond;
// Assume that lower-than-SD resolution are intended for streaming, and use a lower bitrate
bitsPerPixel = numPixels < (640 * 480) ? 4.05F : 11.4F;
bitsPerSecond = (int) (numPixels * bitsPerPixel);
NSDictionary videoCompressionSettings = NSDictionary.FromObjectsAndKeys (
new NSObject[]
{ // The Compression Settings Values
AVVideo.CodecH264,
NSNumber.FromInt32 (dimensions.Width),
NSNumber.FromInt32 (dimensions.Height),
NSDictionary.FromObjectsAndKeys (
new object[]
{ // Compression Property Values
NSNumber.FromInt32 (bitsPerSecond),
NSNumber.FromInt32 (30)
},
new object[]
{ // Compression Property Keys
AVVideo.AverageBitRateKey,
AVVideo.MaxKeyFrameIntervalKey
})
},
new NSObject[]
{ // The Compression Settings Keys
AVVideo.CodecKey,
AVVideo.WidthKey,
AVVideo.HeightKey,
AVVideo.CompressionPropertiesKey
}
);
if (assetWriter.CanApplyOutputSettings (videoCompressionSettings, AVMediaType.Video)){
assetWriterVideoIn = new AVAssetWriterInput (AVMediaType.Video, videoCompressionSettings);
assetWriterVideoIn.ExpectsMediaDataInRealTime = true;
assetWriterVideoIn.Transform = TransformFromCurrentVideoOrientationToOrientation (ReferenceOrientation);
if (assetWriter.CanAddInput (assetWriterVideoIn))
assetWriter.AddInput (assetWriterVideoIn);
else {
Console.WriteLine ("Couldn't add asset writer video input.");
return false;
}
} else
Console.WriteLine ("Couldn't apply video output settings.");
return true;
}
public bool SetupAssetWriterAudioInput (CMFormatDescription currentFormatDescription)
{
// If the AudioStreamBasicDescription is null return false;
if (!currentFormatDescription.AudioStreamBasicDescription.HasValue)
return false;
var currentASBD = currentFormatDescription.AudioStreamBasicDescription.Value;
// Get the Audio Channel Layout from the Format Description.
var currentChannelLayout = currentFormatDescription.AudioChannelLayout;
var currentChannelLayoutData = currentChannelLayout == null ? new NSData () : currentChannelLayout.AsData ();
NSDictionary audioCompressionSettings = NSDictionary.FromObjectsAndKeys (
new NSObject[]
{
NSNumber.FromInt32 ((int)AudioFormatType.MPEG4AAC),
NSNumber.FromDouble (currentASBD.SampleRate),
NSNumber.FromInt32 (64000),
NSNumber.FromInt32 (currentASBD.ChannelsPerFrame),
currentChannelLayoutData
},
new NSObject[]
{
AVAudioSettings.AVFormatIDKey,
AVAudioSettings.AVSampleRateKey,
AVAudioSettings.AVEncoderBitRateKey,
AVAudioSettings.AVNumberOfChannelsKey,
new NSString("AVChannelLayoutKey") //AVAudioSettings.AVChannelLayoutKey,
});
if (assetWriter.CanApplyOutputSettings (audioCompressionSettings, AVMediaType.Audio)){
assetWriterAudioIn = new AVAssetWriterInput (AVMediaType.Audio, audioCompressionSettings);
assetWriterAudioIn.ExpectsMediaDataInRealTime = true;
if (assetWriter.CanAddInput (assetWriterAudioIn))
assetWriter.AddInput (assetWriterAudioIn);
else {
Console.WriteLine ("Couldn't add asset writer audio input.");
return false;
}
} else {
Console.WriteLine ("Couldn't apply audio output settings.");
return false;
}
return true;
}
// HACK: Change CMFormatDescription to CMVideoFormatDescription
public bool SetupAssetWriterVideoInput (CMVideoFormatDescription currentFormatDescription)
{
//Console.WriteLine ("Setting up Video Asset Writer");
float bitsPerPixel;
// HACK: Change VideoDimensions to Dimensions, as this type was changed to CMVideoFormatDescription
var dimensions = currentFormatDescription.Dimensions;
int numPixels = dimensions.Width * dimensions.Height;
int bitsPerSecond;
// Assume that lower-than-SD resolution are intended for streaming, and use a lower bitrate
bitsPerPixel = numPixels < (640 * 480) ? 4.05F : 11.4F;
bitsPerSecond = (int) (numPixels * bitsPerPixel);
NSDictionary videoCompressionSettings = new NSDictionary (
AVVideo.CodecKey, AVVideo.CodecH264,
AVVideo.WidthKey, dimensions.Width,
AVVideo.HeightKey,dimensions.Height,
AVVideo.CompressionPropertiesKey, new NSDictionary(
AVVideo.AverageBitRateKey, bitsPerSecond,
AVVideo.MaxKeyFrameIntervalKey, 30
)
);
if (assetWriter.CanApplyOutputSettings (videoCompressionSettings, AVMediaType.Video)){
// HACK: Change NSDictionary into AVVideoSettingsCompressed created using that NSDictionary (videoCompressionSettings)
assetWriterVideoIn = new AVAssetWriterInput (AVMediaType.Video, new AVVideoSettingsCompressed( videoCompressionSettings));
assetWriterVideoIn.ExpectsMediaDataInRealTime = true;
assetWriterVideoIn.Transform = TransformFromCurrentVideoOrientationToOrientation (ReferenceOrientation);
if (assetWriter.CanAddInput (assetWriterVideoIn))
assetWriter.AddInput (assetWriterVideoIn);
else {
Console.WriteLine ("Couldn't add asset writer video input.");
return false;
}
} else
Console.WriteLine ("Couldn't apply video output settings.");
return true;
}
public AudioChannel (AVAssetReaderOutput readerOutput, AVAssetWriterInput writerInput)
: base(readerOutput, writerInput)
{
}
public bool SetupAssetWriterAudioInput (CMFormatDescription currentFormatDescription)
{
// If the AudioStreamBasicDescription is null return false;
if (!currentFormatDescription.AudioStreamBasicDescription.HasValue)
return false;
var currentASBD = currentFormatDescription.AudioStreamBasicDescription.Value;
// Get the Audio Channel Layout from the Format Description.
var currentChannelLayout = currentFormatDescription.AudioChannelLayout;
var currentChannelLayoutData = currentChannelLayout == null ? new NSData () : currentChannelLayout.AsData ();
NSDictionary audioCompressionSettings = new NSDictionary (
AVAudioSettings.AVFormatIDKey, AudioFormatType.MPEG4AAC,
AVAudioSettings.AVSampleRateKey, currentASBD.SampleRate,
AVAudioSettings.AVEncoderBitRateKey, 64000,
AVAudioSettings.AVNumberOfChannelsKey, currentASBD.ChannelsPerFrame,
AVAudioSettings.AVChannelLayoutKey, currentChannelLayoutData
);
if (assetWriter.CanApplyOutputSettings (audioCompressionSettings, AVMediaType.Audio)){
// HACK: Change NSDictionary into AudioSettings created using that NSDictionary (audioCompressionSettings)
assetWriterAudioIn = new AVAssetWriterInput (AVMediaType.Audio, new AudioSettings(audioCompressionSettings));
assetWriterAudioIn.ExpectsMediaDataInRealTime = true;
if (assetWriter.CanAddInput (assetWriterAudioIn))
assetWriter.AddInput (assetWriterAudioIn);
else {
Console.WriteLine ("Couldn't add asset writer audio input.");
return false;
}
} else {
Console.WriteLine ("Couldn't apply audio output settings.");
return false;
}
return true;
}
void SetupAssetReaserWriterForVideo (AVAssetTrack videoTrack)
{
if (videoTrack == null)
return;
// Decompress to ARGB with the asset reader
var decompSettings = new AVVideoSettingsUncompressed {
PixelFormatType = CVPixelFormatType.CV32BGRA,
AllocateWithIOSurface = null
};
AVAssetReaderOutput output = new AVAssetReaderTrackOutput (videoTrack, decompSettings);
assetReader.AddOutput (output);
// Get the format description of the track, to fill in attributes of the video stream that we don't want to change
var formatDescription = (CMVideoFormatDescription)videoTrack.FormatDescriptions.FirstOrDefault ();
// Grab track dimensions from format description
CGSize trackDimensions = formatDescription != null
? formatDescription.GetPresentationDimensions (false, false)
: videoTrack.NaturalSize;
// Grab clean aperture, pixel aspect ratio from format description
AVVideoCodecSettings compressionSettings = null;
if (formatDescription != null) {
var cleanApertureDescr = (NSDictionary)formatDescription.GetExtension (CVImageBuffer.CleanApertureKey);
var pixelAspectRatioDescr = (NSDictionary)formatDescription.GetExtension (CVImageBuffer.PixelAspectRatioKey);
compressionSettings = CreateCodecSettingsFor (cleanApertureDescr, pixelAspectRatioDescr);
}
// Compress to H.264 with the asset writer
var videoSettings = new AVVideoSettingsCompressed {
Codec = AVVideoCodec.H264,
Width = (int)trackDimensions.Width,
Height = (int)trackDimensions.Height,
CodecSettings = compressionSettings
};
AVAssetWriterInput input = new AVAssetWriterInput (videoTrack.MediaType, videoSettings);
input.Transform = videoTrack.PreferredTransform;
assetWriter.AddInput (input);
// Create and save an instance of ReadWriteSampleBufferChannel,
// which will coordinate the work of reading and writing sample buffers
videoSampleBufferChannel = new VideoChannel (output, input, transformer);
}
protected AVAssetWriterInput MaybeInitializeInputWriter()
{
try
{
var dictionary = NSDictionary.FromObjectsAndKeys(
new NSObject[] { AVVideo.CodecH264, new NSNumber(640), new NSNumber(480) },
new NSObject[] { AVVideo.CodecKey, AVVideo.WidthKey, AVVideo.HeightKey }
);
var writerInput = new AVAssetWriterInput(AVMediaType.Video, dictionary);
writerInput.ExpectsMediaDataInRealTime = true;
return writerInput;
}
catch (Exception x)
{
Failure.Alert(x.Message);
return null;
}
}
public bool StartRecording()
{
try
{
session = MaybeInitializeSession();
if (session == null)
{
Failure.Alert("Couldn't initialize session");
return false;
}
writer = MaybeInitializeAssetWriter();
if (writer == null)
{
Failure.Alert("Couldn't initialize writer");
return false;
}
inputWriter = MaybeInitializeInputWriter();
if (inputWriter == null)
{
Failure.Alert("Couldn't initialize input writer");
return false;
}
if (!writer.CanAddInput(inputWriter))
{
Failure.Alert("Couldn't add input writer to writer");
return false;
}
writer.AddInput(inputWriter);
session.StartRunning();
return true;
}
catch (Exception x)
{
Failure.Alert(x.Message);
return false;
}
}
public AudioChannel(AVAssetReaderOutput readerOutput, AVAssetWriterInput writerInput)
: base(readerOutput, writerInput)
{
}
