RTP Sequence Analyzer

Measure gaps, duplicates and out-of-order transitions in RTP sequence samples.

Protocol scope and method

The calculation handles 16-bit wraparound between adjacent samples. Capture loss before the first sample cannot be inferred.

forwardDelta = (current - previous + 65536) mod 65536.

Diagnostic scenario

Collect sequence numbers from one SSRC in capture order after removing unrelated flows and retransmitted capture duplicates. Analyze gaps, duplicates, reverse transitions and 65535-to-0 wraparound, then compare suspected loss with packet timestamps and capture statistics.

How to interpret the result

A forward gap estimates missing sequence values within the observed sample, not network loss before capture or before the first packet. Reordering can temporarily look like loss and then produce an out-of-order packet. Analyze per SSRC and over a bounded interval.

Input reference

Sequence numbers
Example default: Sample input included

Common mistakes

  • Using an unredacted production capture with vehicle, credential or network identifiers.
  • Combining sequence numbers from multiple SSRC values.
  • Treating a successfully parsed sample as standards compliance or interoperability proof.

Before using the result

  1. Confirm the protocol edition, transport framing and vendor profile before interpreting fields.
  2. Confirm gaps against later packets, timestamps and capture loss counters.
  3. Keep a redacted known-good and known-bad sample as a regression pair.

Questions to check during diagnosis

Does the RTP Sequence Analyzer leave my browser?

No application upload is used. Avoid putting sensitive production data in shareable URLs.

Is this a standards compliance test?

No. Confirm the edition and vendor profile with licensed documents and your target platform.

Offline diagnostic aid. Verify fields, version and vendor extensions before production use.

Detailed engineering guide

JT/T 1078 media diagnostics: packet headers, RTP timing, PS and H.264

A black screen can originate in signaling, transport loss, timestamp handling, PS reconstruction or codec data. This guide isolates each layer in order.

Read the guide