Unable to publish two LocalVideoTracks

[darrenW04]

Describe the bug When publishing two separate LocalVideoTracks into a room, only one track is shown within a room. Using Apple's AVFoundation's AVMultiCamSession, I can locally preview my front and back camera but when I publish both of them, only the most recent track is shown in the room. For clarification if I was confusing

• If I push the tracks sequentially, the most recent track will be the only one that isn't frozen
• Only one track is shown even if I have multiple published
• It disables my local previews (not using live kits track preview, just a preview of the device input locally)
• I made sure my device is capable of hosting the front and back cam simultaneously via the local preview I made.

SDK Version Swift SDK 2.0.11

iOS/macOS Version IOS version 17.0

Xcode Version swift-driver version: 1.90.11.1 Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4) Target: arm64-apple-macosx14.0

Steps to Reproduce In implementing the dual camera feature for both the front and back, I used this repo as an example on how preview multiple cameras simultaneously. https://github.com/jwamin/Multicam/blob/master/Trois-cam/CameraView.swift After you would create a way to connect to the room and have abilities to publish certain tracks. Below is how I would publish my front camera track. The device I'm using is from the AVCaptureMultiCamSession as it holds an array of inputs. In my case index 0 the back cam and index 1 the front cam. func turnFrontCameraOn() { Task { do { let frontCam = captureSession?.inputs[1] as? AVCaptureDeviceInput let track = LocalVideoTrack.createCameraTrack(name: "frontCT", options: CameraCaptureOptions( device: frontCam?.device, dimensions: .h720_169, fps: 30 )) try await room?.localParticipant.publish(videoTrack: track, options: VideoPublishOptions(name: "front", encoding: VideoEncoding(maxBitrate: 128, maxFps: 60), streamName: "frontS")) } catch { print(error) } } } From here on you can connect to a web app such as https://meet.livekit.io/?tab=custom to view the tracks from another participant.

Expected behavior Wanted Result: View two tracks of the front and back camera My result: Only the most recent track has a camera shown, I will show an example in the screenshots, with the right image being the most recent Note when publishing tracks one by one, each track works until another track is published

Screenshots

[hiroshihorie]

Thanks for the detailed report, I'm thinking we need to expose ability to set custom AVCaptureSession such as AVCaptureMultiCamSession.

[hiroshihorie]

Patching WebRTC to see if this will work. https://github.com/webrtc-sdk/webrtc/pull/132