diff --git a/SJSAssetExportSession.xcodeproj/project.pbxproj b/SJSAssetExportSession.xcodeproj/project.pbxproj index 0e4541f..42ed0f3 100644 --- a/SJSAssetExportSession.xcodeproj/project.pbxproj +++ b/SJSAssetExportSession.xcodeproj/project.pbxproj @@ -16,6 +16,7 @@ 7BC5FC772C3B8C5A0090B757 /* SendableWrapper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7BC5FC762C3B8C5A0090B757 /* SendableWrapper.swift */; }; 7BC5FC792C3B90F70090B757 /* AutoDestructingURL.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7BC5FC782C3B90F70090B757 /* AutoDestructingURL.swift */; }; 7BC5FC7B2C3B93270090B757 /* AVFoundation+sending.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7BC5FC7A2C3B93270090B757 /* AVFoundation+sending.swift */; }; + 7BC5FC8A2C3BAA150090B757 /* ExportSession+Error.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7BC5FC892C3BAA150090B757 /* ExportSession+Error.swift */; }; /* End PBXBuildFile section */ /* Begin PBXContainerItemProxy section */ @@ -39,6 +40,7 @@ 7BC5FC762C3B8C5A0090B757 /* SendableWrapper.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SendableWrapper.swift; sourceTree = ""; }; 7BC5FC782C3B90F70090B757 /* AutoDestructingURL.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AutoDestructingURL.swift; sourceTree = ""; }; 7BC5FC7A2C3B93270090B757 /* AVFoundation+sending.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "AVFoundation+sending.swift"; sourceTree = ""; }; + 7BC5FC892C3BAA150090B757 /* ExportSession+Error.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "ExportSession+Error.swift"; sourceTree = ""; }; /* End PBXFileReference section */ /* Begin PBXFileSystemSynchronizedRootGroup section */ @@ -85,10 +87,11 @@ 7B9BC00B2C305D2C00C160C2 /* SJSAssetExportSession */ = { isa = PBXGroup; children = ( + 7B9BC0272C30612C00C160C2 /* ExportSession.swift */, + 7BC5FC892C3BAA150090B757 /* ExportSession+Error.swift */, + 7B7AE3082C36615700DB7391 /* SampleWriter.swift */, 7B9BC00C2C305D2C00C160C2 /* SJSAssetExportSession.h */, 7B9BC00D2C305D2C00C160C2 /* SJSAssetExportSession.docc */, - 7B9BC0272C30612C00C160C2 /* ExportSession.swift */, - 7B7AE3082C36615700DB7391 /* SampleWriter.swift */, ); path = SJSAssetExportSession; sourceTree = ""; @@ -220,6 +223,7 @@ 7B7AE3092C36615700DB7391 /* SampleWriter.swift in Sources */, 7B9BC0282C30612C00C160C2 /* ExportSession.swift in Sources */, 7B9BC00E2C305D2C00C160C2 /* SJSAssetExportSession.docc in Sources */, + 7BC5FC8A2C3BAA150090B757 /* ExportSession+Error.swift in Sources */, ); runOnlyForDeploymentPostprocessing = 0; }; diff --git a/SJSAssetExportSession/ExportSession+Error.swift b/SJSAssetExportSession/ExportSession+Error.swift new file mode 100644 index 0000000..9ee7115 --- /dev/null +++ b/SJSAssetExportSession/ExportSession+Error.swift @@ -0,0 +1,75 @@ +// +// ExportSession+Error.swift +// SJSAssetExportSession +// +// Created by Sami Samhuri on 2024-07-07. +// + +import Foundation + +extension ExportSession { + public enum SetupFailureReason: String, Sendable, CustomStringConvertible { + case audioSettingsEmpty + case audioSettingsInvalid + case cannotAddAudioInput + case cannotAddAudioOutput + case cannotAddVideoInput + case cannotAddVideoOutput + case videoSettingsEmpty + case videoSettingsInvalid + case videoTracksEmpty + + public var description: String { + switch self { + case .audioSettingsEmpty: + "Must provide audio output settings" + case .audioSettingsInvalid: + "Invalid audio output settings" + case .cannotAddAudioInput: + "Can't add audio input to writer" + case .cannotAddAudioOutput: + "Can't add audio output to reader" + case .cannotAddVideoInput: + "Can't add video input to writer" + case .cannotAddVideoOutput: + "Can't add video output to reader" + case .videoSettingsEmpty: + "Must provide video output settings" + case .videoSettingsInvalid: + "Invalid video output settings" + case .videoTracksEmpty: + "No video track" + } + } + } + + public enum Error: LocalizedError, Equatable { + case setupFailure(SetupFailureReason) + case readFailure((any Swift.Error)?) + case writeFailure((any Swift.Error)?) + + public var errorDescription: String? { + switch self { + case let .setupFailure(reason): + reason.description + case let .readFailure(underlyingError): + underlyingError?.localizedDescription ?? "Unknown read failure" + case let .writeFailure(underlyingError): + underlyingError?.localizedDescription ?? "Unknown write failure" + } + } + + public static func == (lhs: ExportSession.Error, rhs: ExportSession.Error) -> Bool { + switch (lhs, rhs) { + case let (.setupFailure(lhsReason), .setupFailure(rhsReason)): + lhsReason == rhsReason + case let (.readFailure(lhsError), .readFailure(rhsError)): + String(describing: lhsError) == String(describing: rhsError) + case let (.writeFailure(lhsError), .writeFailure(rhsError)): + String(describing: lhsError) == String(describing: rhsError) + default: + false + } + } + } +} diff --git a/SJSAssetExportSession/ExportSession.swift b/SJSAssetExportSession/ExportSession.swift index 9411b16..be89700 100644 --- a/SJSAssetExportSession/ExportSession.swift +++ b/SJSAssetExportSession/ExportSession.swift @@ -8,72 +8,8 @@ public import AVFoundation -// @unchecked Sendable because progress properties are mutable, it's safe though. public final class ExportSession: @unchecked Sendable { - public enum SetupFailureReason: String, Sendable, CustomStringConvertible { - case audioSettingsEmpty - case audioSettingsInvalid - case cannotAddAudioInput - case cannotAddAudioOutput - case cannotAddVideoInput - case cannotAddVideoOutput - case videoSettingsEmpty - case videoSettingsInvalid - case videoTracksEmpty - - public var description: String { - switch self { - case .audioSettingsEmpty: - "Must provide audio output settings" - case .audioSettingsInvalid: - "Invalid audio output settings" - case .cannotAddAudioInput: - "Can't add audio input to writer" - case .cannotAddAudioOutput: - "Can't add audio output to reader" - case .cannotAddVideoInput: - "Can't add video input to writer" - case .cannotAddVideoOutput: - "Can't add video output to reader" - case .videoSettingsEmpty: - "Must provide video output settings" - case .videoSettingsInvalid: - "Invalid video output settings" - case .videoTracksEmpty: - "No video track" - } - } - } - - public enum Error: LocalizedError, Equatable { - case setupFailure(SetupFailureReason) - case readFailure((any Swift.Error)?) - case writeFailure((any Swift.Error)?) - - public var errorDescription: String? { - switch self { - case let .setupFailure(reason): - reason.description - case let .readFailure(underlyingError): - underlyingError?.localizedDescription ?? "Unknown read failure" - case let .writeFailure(underlyingError): - underlyingError?.localizedDescription ?? "Unknown write failure" - } - } - - public static func == (lhs: ExportSession.Error, rhs: ExportSession.Error) -> Bool { - switch (lhs, rhs) { - case let (.setupFailure(lhsReason), .setupFailure(rhsReason)): - lhsReason == rhsReason - case let (.readFailure(lhsError), .readFailure(rhsError)): - String(describing: lhsError) == String(describing: rhsError) - case let (.writeFailure(lhsError), .writeFailure(rhsError)): - String(describing: lhsError) == String(describing: rhsError) - default: - false - } - } - } + // @unchecked Sendable because progress properties are mutable, it's safe though. public typealias ProgressStream = AsyncStream @@ -87,6 +23,33 @@ public final class ExportSession: @unchecked Sendable { } } + /** + Exports the given asset using all of the other parameters to transform it in some way. + + - Parameters: + - asset: The source asset to export. This can be any kind of `AVAsset` including subclasses such as `AVComposition`. + + - audioMix: An optional mix that can be used to manipulate the audio in some way. + + - audioOutputSettings: Audio settings using [audio settings keys from AVFoundation](https://developer.apple.com/documentation/avfoundation/audio_settings) and values must be suitable for consumption by Objective-C. Required keys are: + - `AVFormatIDKey` with the typical value `kAudioFormatMPEG4AAC` + - `AVNumberOfChannelsKey` with the typical value `NSNumber(value: 2)` or `AVChannelLayoutKey` with an instance of `AVAudioChannelLayout` + + - videoComposition: Used to manipulate the video in some way. This can be used to scale the video, apply filters, amongst other edits. + + - videoOutputSettings: Video settings using [video settings keys from AVFoundation](https://developer.apple.com/documentation/avfoundation/video_settings) and values must be suitable for consumption by Objective-C. Required keys are: + - `AVVideoCodecKey` with the typical value `AVVideoCodecType.h264.rawValue` or `AVVideoCodecType.hevc.rawValue` + - `AVVideoWidthKey` with an integer as an `NSNumber` + - `AVVideoHeightKey` with an integer as an `NSNumber` + + - timeRange: Providing a time range exports a subset of the asset instead of the entire duration, which is the default behaviour. + + - optimizeForNetworkUse: Setting this value to `true` writes the output file in a form that enables a player to begin playing the media after downloading only a small portion of it. Defaults to `false`. + + - outputURL: The file URL where the exported video will be written. + + - fileType: The type of of video file to export. This will typically be one of `AVFileType.mp4`, `AVFileType.m4v`, or `AVFileType.mov`. + */ public func export( asset: sending AVAsset, audioMix: sending AVAudioMix?, @@ -100,11 +63,11 @@ public final class ExportSession: @unchecked Sendable { ) async throws { let sampleWriter = try await SampleWriter( asset: asset, - timeRange: timeRange ?? CMTimeRange(start: .zero, duration: .positiveInfinity), audioMix: audioMix, audioOutputSettings: audioOutputSettings, videoComposition: videoComposition, videoOutputSettings: videoOutputSettings, + timeRange: timeRange, optimizeForNetworkUse: optimizeForNetworkUse, outputURL: outputURL, fileType: fileType diff --git a/SJSAssetExportSession/SampleWriter.swift b/SJSAssetExportSession/SampleWriter.swift index de00310..8899ae4 100644 --- a/SJSAssetExportSession/SampleWriter.swift +++ b/SJSAssetExportSession/SampleWriter.swift @@ -19,92 +19,66 @@ private extension AVAsset { actor SampleWriter { typealias Error = ExportSession.Error + // MARK: - Actor executor + private let queue = DispatchSerialQueue( label: "SJSAssetExportSession.SampleWriter", autoreleaseFrequency: .workItem, target: .global() ) + // Execute this actor on the same queue we use to request media data so we can use + // `assumeIsolated` to ensure that we public nonisolated var unownedExecutor: UnownedSerialExecutor { queue.asUnownedSerialExecutor() } - private let audioMix: AVAudioMix? - - private let audioOutputSettings: [String: (any Sendable)] - - private let videoComposition: AVVideoComposition? - - private let videoOutputSettings: [String: (any Sendable)] - - private let reader: AVAssetReader - - private let writer: AVAssetWriter - - private let duration: CMTime - - private let timeRange: CMTimeRange - - private var audioOutput: AVAssetReaderAudioMixOutput? - - private var audioInput: AVAssetWriterInput? - - private var videoOutput: AVAssetReaderVideoCompositionOutput? - - private var videoInput: AVAssetWriterInput? - lazy var progressStream: AsyncStream = AsyncStream { continuation in progressContinuation = continuation } - private var progressContinuation: AsyncStream.Continuation? + private let audioMix: AVAudioMix? + private let audioOutputSettings: [String: (any Sendable)] + private let videoComposition: AVVideoComposition? + private let videoOutputSettings: [String: (any Sendable)] + private let reader: AVAssetReader + private let writer: AVAssetWriter + private let duration: CMTime + private let timeRange: CMTimeRange + private var audioOutput: AVAssetReaderAudioMixOutput? + private var audioInput: AVAssetWriterInput? + private var videoOutput: AVAssetReaderVideoCompositionOutput? + private var videoInput: AVAssetWriterInput? + init( asset: sending AVAsset, - timeRange: CMTimeRange, audioMix: AVAudioMix?, audioOutputSettings: sending [String: (any Sendable)], videoComposition: AVVideoComposition, videoOutputSettings: sending [String: (any Sendable)], - optimizeForNetworkUse: Bool, + timeRange: CMTimeRange? = nil, + optimizeForNetworkUse: Bool = false, outputURL: URL, fileType: AVFileType ) async throws { - guard !videoOutputSettings.isEmpty else { - throw Error.setupFailure(.videoSettingsEmpty) - } - let duration = - if timeRange.duration.isValid && !timeRange.duration.isPositiveInfinity { - timeRange.duration - } else { - try await asset.load(.duration) - } - + if let timeRange { timeRange.duration } else { try await asset.load(.duration) } let reader = try AVAssetReader(asset: asset) - reader.timeRange = timeRange - + if let timeRange { + reader.timeRange = timeRange + } let writer = try AVAssetWriter(outputURL: outputURL, fileType: fileType) writer.shouldOptimizeForNetworkUse = optimizeForNetworkUse let audioTracks = try await asset.sendTracks(withMediaType: .audio) - if !audioTracks.isEmpty { - guard !audioOutputSettings.isEmpty else { - throw Error.setupFailure(.audioSettingsEmpty) - } - guard writer.canApply(outputSettings: audioOutputSettings, forMediaType: .audio) else { - throw Error.setupFailure(.audioSettingsInvalid) - } - } - + try Self.validateAudio(tracks: audioTracks, outputSettings: audioOutputSettings, writer: writer) let videoTracks = try await asset.sendTracks(withMediaType: .video) - guard !videoTracks.isEmpty else { - throw Error.setupFailure(.videoTracksEmpty) - } - guard writer.canApply(outputSettings: videoOutputSettings, forMediaType: .video) else { - throw Error.setupFailure(.videoSettingsInvalid) - } - + try Self.validateVideo(tracks: videoTracks, outputSettings: videoOutputSettings, writer: writer) + Self.warnAboutMismatchedVideoDimensions( + renderSize: videoComposition.renderSize, + settings: videoOutputSettings + ) self.audioMix = audioMix self.audioOutputSettings = audioOutputSettings @@ -113,7 +87,7 @@ actor SampleWriter { self.reader = reader self.writer = writer self.duration = duration - self.timeRange = timeRange + self.timeRange = timeRange ?? CMTimeRange(start: .zero, duration: duration) try setUpAudio(audioTracks: audioTracks) try setUpVideo(videoTracks: videoTracks) @@ -156,6 +130,8 @@ actor SampleWriter { await Task.yield() } + // MARK: - Setup + private func setUpAudio(audioTracks: [AVAssetTrack]) throws { guard !audioTracks.isEmpty else { return } @@ -201,34 +177,10 @@ actor SampleWriter { self.videoInput = videoInput } - private func writeReadySamples(output: AVAssetReaderOutput, input: AVAssetWriterInput) -> Bool { - while input.isReadyForMoreMediaData { - guard reader.status == .reading && writer.status == .writing, - let sampleBuffer = output.copyNextSampleBuffer() else { - input.markAsFinished() - log.debug("Finished encoding ready audio samples from \(output)") - return false - } - - let samplePresentationTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer) - timeRange.start - let progress = Float(samplePresentationTime.seconds / duration.seconds) - progressContinuation?.yield(progress) - - guard input.append(sampleBuffer) else { - log.error(""" - Failed to append audio sample buffer \(String(describing: sampleBuffer)) to - input \(input.debugDescription) - """) - return false - } - } - - // Everything was appended successfully, return true indicating there's more to do. - log.debug("Completed encoding ready audio samples, more to come...") - return true - } + // MARK: - Encoding private func encodeAudioTracks() async { + // Don't do anything when we have no audio to encode. guard audioInput != nil, audioOutput != nil else { return } return await withCheckedContinuation { continuation in @@ -255,4 +207,73 @@ actor SampleWriter { } } } + + private func writeReadySamples(output: AVAssetReaderOutput, input: AVAssetWriterInput) -> Bool { + while input.isReadyForMoreMediaData { + guard reader.status == .reading && writer.status == .writing, + let sampleBuffer = output.copyNextSampleBuffer() else { + input.markAsFinished() + return false + } + + // Only yield progress values for video. Audio is insignificant in comparison. + if output == videoOutput { + let samplePresentationTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer) - timeRange.start + let progress = Float(samplePresentationTime.seconds / duration.seconds) + progressContinuation?.yield(progress) + } + + guard input.append(sampleBuffer) else { + log.error(""" + Failed to append audio sample buffer \(String(describing: sampleBuffer)) to + input \(input.debugDescription) + """) + return false + } + } + + // Everything was appended successfully, return true indicating there's more to do. + return true + } + + // MARK: Input validation + + private static func validateAudio( + tracks: [AVAssetTrack], + outputSettings: [String: any Sendable], + writer: AVAssetWriter + ) throws { + guard !tracks.isEmpty else { return } // Audio is optional so this isn't a failure. + guard !outputSettings.isEmpty else { throw Error.setupFailure(.audioSettingsEmpty) } + guard writer.canApply(outputSettings: outputSettings, forMediaType: .audio) else { + throw Error.setupFailure(.audioSettingsInvalid) + } + } + + private static func validateVideo( + tracks: [AVAssetTrack], + outputSettings: [String: any Sendable], + writer: AVAssetWriter + ) throws { + guard !tracks.isEmpty else { throw Error.setupFailure(.videoTracksEmpty) } + guard !outputSettings.isEmpty else { throw Error.setupFailure(.videoSettingsEmpty) } + guard writer.canApply(outputSettings: outputSettings, forMediaType: .video) else { + throw Error.setupFailure(.videoSettingsInvalid) + } + } + + private static func warnAboutMismatchedVideoDimensions( + renderSize: CGSize, + settings: [String: any Sendable] + ) { + guard let settingsWidth = (settings[AVVideoWidthKey] as? NSNumber)?.intValue, + let settingsHeight = (settings[AVVideoHeightKey] as? NSNumber)?.intValue + else { return } + + let renderWidth = Int(renderSize.width) + let renderHeight = Int(renderSize.height) + if renderWidth != settingsWidth || renderHeight != settingsHeight { + log.warning("Video composition's render size (\(renderWidth)ｘ\(renderHeight)) will be overriden by video output settings (\(settingsWidth)ｘ\(settingsHeight))") + } + } } diff --git a/SJSAssetExportSessionTests/AutoDestructingURL.swift b/SJSAssetExportSessionTests/AutoDestructingURL.swift index 1e160d8..e15b63a 100644 --- a/SJSAssetExportSessionTests/AutoDestructingURL.swift +++ b/SJSAssetExportSessionTests/AutoDestructingURL.swift @@ -8,7 +8,7 @@ import Foundation import OSLog -private let log = Logger(OSLog(subsystem: "SJSAssetExportSessionTests", category: "AutoDestructingURL")) +private let log = Logger(subsystem: "SJSAssetExportSessionTests", category: "AutoDestructingURL") /// Wraps a URL and deletes it when this instance is deallocated. Failures to delete the file are logged. final class AutoDestructingURL: Hashable, Sendable {