Stream events

Stream online calendar

The stream online calendar displays a heatmap visualization of your stream's uptime activity over the last 120 days.

To view the stream online calendar, press the Stream calendar button:
Stream events button

The stream online calendar provides a quick visual overview of streaming patterns and identifies gaps or irregular activity.
Stream online calendar

Understanding the heatmap

The calendar uses color intensity to represent daily streaming duration:

  • Empty/Gray – No streaming activity recorded on that day
  • Light Green – Short sessions (1–4 hours of streaming)
  • Medium Green – Moderate sessions (4–8 hours of streaming)
  • Dark Green – Long sessions (8+ hours of streaming)

Each small square represents one calendar day, organized by week in columns. Weekends are typically less active or absent depending on your streaming schedule. The view automatically highlights your stream's operational patterns, making it easy to spot:

  • Regular weekday streaming activity
  • Occasional weekend streams
  • Days with no activity (maintenance, off-days)
  • Extended streaming sessions

Customizing the calendar layout

You can configure the calendar to display weeks starting on Monday (default) or Sunday based on your preference (Client preferences->Misc). This allows the calendar to align with your local work week convention or regional calendar standards.

Viewing detailed event history

To view the stream's detailed activity and error history, press the Stream Events Timeline button:
Stream events button

This opens the timeline view, which presents a chronological list of events related to the selected stream.
Stream events button

The timeline shows:

  • Stream interruptions or timeouts
  • Detected errors such as Continuity Counter or PCR Discontinuities
  • Loss or recovery of the stream (Offline/Online)
  • Any other important status changes

MpegTS errors detection

SkyView application detects some common MPEG-TS transport stream integrity issues, specifically Continuity Counter errors and PCR discontinuities. These checks help identify packet loss, duplication, or timestamp irregularities in transport streams.

Hovering the mouse over an event displays a tooltip with additional detailed information about that event - for example, the PID involved or a more descriptive explanation of the detected error.

Continuity Counter (CC) Errors

Each MPEG-TS packet contains a Continuity Counter (CC) field - 4 bits in the packet header (byte 3, bits 0–3). It increments by 1 (mod 16) for consecutive packets with the same PID that carry payload data.
If packets are lost, repeated, or reordered, the counter sequence will break.

Common Causes:

  • Lost UDP packets
  • Reordered network traffic
  • Encoder or remultiplexer bug
  • PID reuse without reset

PCR (Program Clock Reference) Discontinuities

The Program Clock Reference (PCR) provides a 27 MHz clock used to synchronize timing between the encoder and decoder.
It is carried in the adaptation field of packets whose PID matches the PMT-declared PCR PID.
The PCR value must increase monotonically and appear at least every 100 ms (ISO/IEC 13818-1).

Errors detected:

  • Backwards/out-of-order PCR if delta < 0 (no wrap).
  • Long gap if delta > 2.7 × 10⁶ ticks (≈ 100 ms at 27 MHz).

Common Causes:

  • Encoder clock instability
  • Bad timestamp rewriting after remux
  • Missing PCR packets

Klv errors detection

SkyView validates ancillary KLV metadata for common issues:

  • Checksum/decoding errors (malformed KLV that fails integrity checks is reported as a decode error)
  • Timestamp-related errors (duplicate timestamps and timestamp regressions/discontinuities)

KLV Timestamp Duplication

When processing ancillary KLV metadata, SkyView checks the embedded timestamp values for each packet (per PID). A duplication occurs when two consecutive KLV packets for the same PID carry an identical timestamp.

Why it matters:

  • Indicates potential encoder or multiplexer defects producing repeated metadata frames.
  • Can reflect stalled metadata generation (sensor not updating position/telemetry).

KLV Timestamp Discontinuity (Regression)

A discontinuity (regression) occurs when a KLV timestamp decreases relative to the previous packet for the same PID (i.e., current < previous). Timestamps are expected to be monotonic for proper temporal correlation of metadata with video.

Why it matters:

  • Downstream consumers may mis-order metadata or drop frames assuming clock skew.
  • Can signal clock resets, wrap handling bugs, or malformed remuxing.