Debug Viewer

Debug Viewer is a single-source diagnostic tool for detailed NDI® stream analysis.

When to Use Debug Viewer

Use Debug Viewer when:

Verifying a source is healthy before assigning it to production multiviewer
Diagnosing why a source looks choppy or unstable
Comparing latency behaviour across different sources or settings
Validating audio channel assignments before a show
Investigating whether dropped frames come from the sender, network, or receiver

Debug Viewer is not for normal monitoring — it’s for engineering validation and troubleshooting.

Opening Debug Viewer

Menu → Help → Open Debug Viewer

A separate window opens with a clean single-viewer interface and detailed statistics panel.

Debug Viewer Interface

Source Selection Panel (Top):

Shows all discovered NDI® sources. Click a source to connect. Local sources and network sources are grouped separately.

Video Display:

Full-screen video playback of the selected source with real-time rendering.

Statistics Panel (Right Side):

Real-time metrics displayed in organized sections:

Connection Status:

Connected/Disconnected state
Source URL and machine name
Current bandwidth mode
Transport type (TCP/UDP/Multicast)

Video Statistics:

Frame count received
Measured FPS (actual frame processing rate)
Signaled FPS (sender’s advertised frame rate)
Resolution (width × height)
Scan type (Progressive/Interlaced)
Pixel format (UYVY, BGRA, etc.)
Estimated bitrate (Mbps)

Performance Metrics:

Video frames received
Video frames dropped
Audio frames received
Audio frames dropped
Metadata frames received
Metadata frames dropped

Latency Analysis:

Average latency (milliseconds)
Current latency (instantaneous measurement)
Minimum latency (best case)
Peak latency (worst case)

Audio Panel:

8-channel or 16-channel audio meters
Audio monitoring toggle (listen to source)
Visual representation of audio levels

Interpreting Statistics

Frame Rate:

If “Measured FPS” stays close to “Signaled FPS”, everything is healthy. If measured FPS is consistently lower, you’re dropping frames somewhere (network, CPU, or GPU bottleneck).

Dropped Frames:

Zero dropped frames = excellent.
Occasional drops (1-5 over several minutes) = acceptable for monitoring.
Continuously increasing drop count = problem (investigate network or system load).

Latency:

Latency values are color-coded for quick assessment:

Green (< 100ms): Excellent performance, no concerns
Yellow (100-150ms): Acceptable for monitoring, usable for most workflows
Red (> 150ms): High latency, investigate settings or network path

Latency Types:

Average latency: Most important metric. Represents typical performance.
Current latency: Instantaneous measurement. Fluctuates second-to-second.
Peak latency: Worst-case spike. Occasional peaks are normal, but sustained peaks indicate issues.

Transport Type:

Shows how NDI® is delivering the stream:

TCP: Reliable, higher CPU overhead, works over Internet
UDP: Lower overhead, requires stable local network
Multicast: Most efficient for multiple receivers on same network segment
RUDP (Reliable UDP): Hybrid approach with retransmission

Auto-negotiation typically chooses the best transport for your environment.

Using Debug Viewer for Pre-Show Validation

Workflow:

Open Debug Viewer before your show
Connect to each source you’ll use in production
Let it run for 60 seconds per source
Verify zero or minimal dropped frames
Check average latency is green or yellow
Confirm audio meters show expected channel activity
Document any issues before going live

If any source shows red latency or continuous frame drops, investigate and resolve before committing to that source for live use.

Debug Viewer Limitations

Debug Viewer is single-source only. You can’t monitor multiple sources simultaneously in Debug Viewer — that’s what the main multiviewer is for.

If you need side-by-side diagnostics, open the main multiviewer in 1x2 layout with both sources, then use Debug Viewer for detailed stats on the problematic source.