The streaming path
Nosmai owns and processes the camera feed. Agora publishes only the processed output while the application keeps its local preview and session controls.
Prerequisites
- Configure Agora broadcaster authentication, audio, and channel lifecycle.
- Configure Agora to publish external video instead of its camera track.
- Pin and test the Agora version used by your application.
Receive processed frames
[NosmaiCore shared].liveFrameStreamCallback =
^(CVPixelBufferRef pixelBuffer, double timestamp) {
CVPixelBufferRetain(pixelBuffer);
dispatch_async(agoraQueue, ^{
[agoraAdapter pushPixelBuffer:pixelBuffer timestamp:timestamp];
CVPixelBufferRelease(pixelBuffer);
});
};
agoraAdapter is the application layer that converts the Nosmai callback into the external-video API used by the pinned Agora release. Do not start Agora's camera while Nosmai owns it.
Preserve ownership and timing
- The callback runs off the main thread.
- Retain the pixel buffer when Agora consumes it asynchronously.
- Preserve the timestamp and configure matching orientation and dimensions.
- Do not block the callback with network, file, or UIKit work.
Stop in the correct order
Stop Agora publishing before clearing the callback:
[NosmaiCore shared].liveFrameStreamCallback = nil;
Then leave the channel and release Agora according to its lifecycle. Keep Nosmai alive if the local camera experience continues.
Common errors
| Symptom | Cause | Fix |
|---|---|---|
| Remote stream is unfiltered | Agora is publishing its own camera track | Disable the camera track and publish the Nosmai processed source |
| Frames corrupt or crash later | The buffer outlived the callback without being retained | Retain before asynchronous use and release after Agora finishes |
| Preview is smooth but remote video rotates | Provider orientation does not match the buffer contract | Test portrait and landscape with the pinned Agora version |
Verify it worked
Apply a visible effect, join from a second device, and confirm the remote video is filtered, correctly oriented, and stable through background and rejoin.
