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design/synchronisation: add missing markup to gst keywords

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Reynaldo H. Verdejo Pinochet 2016-12-19 15:25:34 -08:00
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markdown/design/synchronisation.md
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@ -3,12 +3,12 @@
This document outlines the techniques used for doing synchronised This document outlines the techniques used for doing synchronised
playback of multiple streams. playback of multiple streams.
Synchronisation in a GstPipeline is achieved using the following 3 Synchronisation in a `GstPipeline` is achieved using the following 3
components: components:
- a GstClock, which is global for all elements in a GstPipeline. - a `GstClock`, which is global for all elements in a `GstPipeline`.
- Timestamps on a GstBuffer. - Timestamps on a `GstBuffer`.
- the SEGMENT event preceding the buffers. - the SEGMENT event preceding the buffers.
@ -19,10 +19,10 @@ nanoseconds. This value is called the absolute\_time.
Different sources exist for this counter: Different sources exist for this counter:
- the system time (with g\_get\_current\_time() and with microsecond - the system time (with `g_get_current_time()` and with microsecond
accuracy) accuracy)
- monotonic time (with g\_get\_monotonic\_time () with microsecond - monotonic time (with `g_get_monotonic_time()` with microsecond
accuracy) accuracy)
- an audio device (based on number of samples played) - an audio device (based on number of samples played)
@ -32,12 +32,12 @@ Different sources exist for this counter:
- … - …
In GStreamer any element can provide a GstClock object that can be used In GStreamer any element can provide a `GstClock` object that can be used
in the pipeline. The GstPipeline object will select a clock from all the in the pipeline. The `GstPipeline` object will select a clock from all the
providers and will distribute it to all other elements (see providers and will distribute it to all other elements (see
[gstpipeline](design/gstpipeline.md)). [gstpipeline](design/gstpipeline.md)).
A GstClock always counts time upwards and does not necessarily start at A `GstClock` always counts time upwards and does not necessarily start at
0. 0.
While it is possible, it is not recommended to create a clock derived While it is possible, it is not recommended to create a clock derived
@ -84,14 +84,14 @@ clock. This value is monotonically increasing at the rate of the clock.
## Timestamps ## Timestamps
The GstBuffer timestamps and the preceding SEGMENT event (See The `GstBuffer` timestamps and the preceding SEGMENT event (See
[streams](design/streams.md)) define a transformation of the buffer timestamps to [streams](design/streams.md)) define a transformation of the buffer timestamps to
running\_time as follows: running\_time as follows:
The following notation is used: The following notation is used:
**B**: GstBuffer **B**: `GstBuffer`
- B.timestamp = buffer timestamp (GST_BUFFER_PTS or GST_BUFFER_DTS) - B.timestamp = buffer timestamp (`GST_BUFFER_PTS` or `GST_BUFFER_DTS`)
**S**: SEGMENT event preceding the buffers. **S**: SEGMENT event preceding the buffers.
- S.start: start field in the SEGMENT event. This is the lowest allowed - S.start: start field in the SEGMENT event. This is the lowest allowed