Add StreamScreenObject.

HaishinKit.xcodeproj/project.pbxproj

@@ -296,6 +296,7 @@
 		BCFB355524FA27EA00DC5108 /* PlaybackViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = BCFB355324FA275600DC5108 /* PlaybackViewController.swift */; };
 		BCFB355A24FA40DD00DC5108 /* PlaybackContainerViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = BCFB355924FA40DD00DC5108 /* PlaybackContainerViewController.swift */; };
 		BCFC51FE2AAB420700014428 /* IOAudioMixerTrack.swift in Sources */ = {isa = PBXBuildFile; fileRef = BCFC51FD2AAB420700014428 /* IOAudioMixerTrack.swift */; };
+		BCFDF6322C82E50600BA9024 /* StreamScreenObject.swift in Sources */ = {isa = PBXBuildFile; fileRef = BCFDF6312C82E50600BA9024 /* StreamScreenObject.swift */; };
 		BCFF640B29C0C44B004EFF2F /* SampleVideo_360x240_5mb_2ch.ts in Resources */ = {isa = PBXBuildFile; fileRef = BCFF640A29C0C44B004EFF2F /* SampleVideo_360x240_5mb_2ch.ts */; };
 /* End PBXBuildFile section */
 
@@ -747,6 +748,7 @@
 		BCFB355324FA275600DC5108 /* PlaybackViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PlaybackViewController.swift; sourceTree = "<group>"; };
 		BCFB355924FA40DD00DC5108 /* PlaybackContainerViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PlaybackContainerViewController.swift; sourceTree = "<group>"; };
 		BCFC51FD2AAB420700014428 /* IOAudioMixerTrack.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = IOAudioMixerTrack.swift; sourceTree = "<group>"; };
+		BCFDF6312C82E50600BA9024 /* StreamScreenObject.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StreamScreenObject.swift; sourceTree = "<group>"; };
 		BCFF640A29C0C44B004EFF2F /* SampleVideo_360x240_5mb_2ch.ts */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.typescript; path = SampleVideo_360x240_5mb_2ch.ts; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
@@ -1326,6 +1328,7 @@
 				BCDEB4F72BE441D300EEC6ED /* ScreenRenderer.swift */,
 				BC3004CD296B0A1700119932 /* Shape.swift */,
 				BC6FC91D29609A6800A746EE /* ShapeFactory.swift */,
+				BCFDF6312C82E50600BA9024 /* StreamScreenObject.swift */,
 				29B8768F1CD70AFE00FC07DA /* VideoEffect.swift */,
 				B317235F2C0940D800C7AED0 /* VideoRotator.swift */,
 			);
@@ -1968,6 +1971,7 @@
 				29B876AC1CD70B2800FC07DA /* AMF3Serializer.swift in Sources */,
 				BC31DBD22A653D1600C4DEA3 /* IOAudioMonitor.swift in Sources */,
 				B31723622C0948E300C7AED0 /* VTRotationSessionOption+Extension.swift in Sources */,
+				BCFDF6322C82E50600BA9024 /* StreamScreenObject.swift in Sources */,
 				BCB976DF26107B5600C9A649 /* TSField.swift in Sources */,
 				BC11024A2925147300D48035 /* IOCaptureUnit.swift in Sources */,
 				29B876921CD70AFE00FC07DA /* IOMixer.swift in Sources */,

Sources/IO/IOStream.swift

@@ -554,7 +554,6 @@ extension IOStream: IOMixerDelegate {
         }
     }
     #endif
-
 }
 
 extension IOStream: IOTellyUnitDelegate {

Sources/Screen/StreamScreenObject.swift

@@ -0,0 +1,69 @@
+import AVFoundation
+import CoreGraphics
+import CoreImage
+import Foundation
+
+/// An object that manages offscreen rendering a streaming video track source.
+public final class StreamScreenObject: ScreenObject, ChromaKeyProcessable {
+    public var chromaKeyColor: CGColor?
+
+    /// The video is displayed within a player layer’s bounds.
+    public var videoGravity: AVLayerVideoGravity = .resizeAspect {
+        didSet {
+            guard videoGravity != oldValue else {
+                return
+            }
+            invalidateLayout()
+        }
+    }
+
+    private var sampleBuffer: CMSampleBuffer? {
+        didSet {
+            guard sampleBuffer != oldValue else {
+                return
+            }
+            if sampleBuffer == nil {
+                return
+            }
+            invalidateLayout()
+        }
+    }
+
+    override public func makeBounds(_ size: CGSize) -> CGRect {
+        guard parent != nil, let image = sampleBuffer?.formatDescription?.dimensions.size else {
+            return super.makeBounds(size)
+        }
+        let bounds = super.makeBounds(size)
+        switch videoGravity {
+        case .resizeAspect:
+            let scale = min(bounds.size.width / image.width, bounds.size.height / image.height)
+            let scaleSize = CGSize(width: image.width * scale, height: image.height * scale)
+            return super.makeBounds(scaleSize)
+        case .resizeAspectFill:
+            return bounds
+        default:
+            return bounds
+        }
+    }
+
+    override public func makeImage(_ renderer: some ScreenRenderer) -> CGImage? {
+        guard let sampleBuffer, let pixelBuffer = sampleBuffer.imageBuffer else {
+            return nil
+        }
+        let image = CIImage(cvPixelBuffer: pixelBuffer).transformed(by: videoGravity.scale(
+            bounds.size,
+            image: pixelBuffer.size
+        ))
+        return renderer.context.createCGImage(image, from: videoGravity.region(bounds, image: image.extent))
+    }
+}
+
+extension StreamScreenObject: IOStreamObserver {
+    // MARK: IOStreamObserver
+    public func stream(_ stream: IOStream, didOutput audio: AVAudioBuffer, when: AVAudioTime) {
+    }
+
+    public func stream(_ stream: IOStream, didOutput video: CMSampleBuffer) {
+        sampleBuffer = video
+    }
+}