Write down the units before calculating
A timescale states how many units correspond to one second. For an original example, use 90,000 units per second, a sample position of 450,000 and a presentation-time offset of 180,000. Their difference is 270,000 units, or three seconds on that relative scale.
If the period starts at ten seconds on the MPD timeline, the mapped position is thirteen seconds. The arithmetic first subtracts the offset, then divides by timescale, then adds the period start. Mixing the order or treating 270,000 as milliseconds gives a different result with no basis in the stated configuration.
Keep sample and presentation origins separate
A sample timeline can begin before the period's presentation origin. A large raw timestamp is therefore not automatically a long episode length or a delay behind live. It can be a position in a different coordinate system.
The cited DASH-IF restricted model makes its own interoperability requirements, including explicit timescale handling. Those restrictions should not be described as the only possible syntax of every DASH presentation. State which model is being applied when checking an authored manifest or comparing a parser's result.
Use timing evidence at the boundary
For an alignment problem, retain the relevant period start, timescale, offset and sample position. Keep audio and video configurations separate if their scales differ. Equal raw numbers in two scales do not automatically mean equal presentation times.
A viewer can provide the content boundary and visible symptom while a developer inspects these fields. Do not manually change offsets in a private manifest as a general repair; that can create new inconsistencies without changing encoded samples. This guide offers a worked conversion and documentation scope, not a claim that a real IPTV Australia DASH timeline was measured or repaired.
Questions about this guide
Are DASH timestamp integers always milliseconds?
No. Use their declared timescale.
Do equal raw timestamps always align two tracks?
No. Scales and timeline offsets must also be considered.