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design: framestep: fix missing markup

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Reynaldo H. Verdejo Pinochet 2017-03-13 15:50:28 -07:00
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commit bb1170ee76
1 changed files with 17 additions and 17 deletions
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markdown/design/framestep.md
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@ -27,8 +27,8 @@ than simple playback.
- Ability to play a certain amount of data at an arbitrary speed. - Ability to play a certain amount of data at an arbitrary speed.
We want a system where we can step frames in PAUSED as well as play We want a system where we can step frames in `PAUSED` as well as play
short segments of data in PLAYING. short segments of data in `PLAYING`.
## Use Cases ## Use Cases
@ -41,14 +41,14 @@ short segments of data in PLAYING.
'-----' '-------' '-----' '------' '-------' '-----' '-------' '-----' '------' '-------'
``` ```
- app sets the pipeline to PAUSED to block on the preroll picture - app sets the pipeline to `PAUSED` to block on the preroll picture
- app seeks to required position in the stream. This can be done - app seeks to required position in the stream. This can be done
with a positive or negative rate depending on the required frame with a positive or negative rate depending on the required frame
stepping direction. stepping direction.
- app steps frames (in `GST_FORMAT_DEFAULT` or `GST_FORMAT_BUFFER)`. The - app steps frames (in `GST_FORMAT_DEFAULT` or `GST_FORMAT_BUFFER)`. The
pipeline loses its PAUSED state until the required number of frames have been pipeline loses its `PAUSED` state until the required number of frames have been
skipped, it then prerolls again. This skipping is purely done in the sink. skipped, it then prerolls again. This skipping is purely done in the sink.
- sink posts `STEP_DONE` with amount of frames stepped and - sink posts `STEP_DONE` with amount of frames stepped and
@ -67,14 +67,14 @@ short segments of data in PLAYING.
'-------' '-----' '------' '-------' '-------' '-----' '------' '-------'
``` ```
- app sets the pipeline to PAUSED to block on the preroll picture - app sets the pipeline to `PAUSED` to block on the preroll picture
- app seeks to required position in the stream. This can be done - app seeks to required position in the stream. This can be done
with a positive or negative rate depending on the required frame with a positive or negative rate depending on the required frame
stepping direction. stepping direction.
- app steps frames (in `GST_FORMAT_DEFAULT` or `GST_FORMAT_BUFFER`) or an - app steps frames (in `GST_FORMAT_DEFAULT` or `GST_FORMAT_BUFFER`) or an
amount of time on the video sink. The pipeline loses its PAUSED state until amount of time on the video sink. The pipeline loses its `PAUSED` state until
the required number of frames have been skipped, it then prerolls again. This the required number of frames have been skipped, it then prerolls again. This
skipping is purely done in the sink. skipping is purely done in the sink.
@ -88,7 +88,7 @@ short segments of data in PLAYING.
### audio/video pipeline in PLAYING ### audio/video pipeline in PLAYING
- app sets the pipeline to PAUSED to block on the preroll picture - app sets the pipeline to `PAUSED` to block on the preroll picture
- app seeks to required position in the stream. This can be done - app seeks to required position in the stream. This can be done
with a positive or negative rate depending on the required frame with a positive or negative rate depending on the required frame
@ -130,32 +130,32 @@ use a seek with a negative rate first to reverse the playback direction.
* **`flush`** `G_TYPE_BOOLEAN`: when flushing is TRUE, the step is performed * **`flush`** `G_TYPE_BOOLEAN`: when flushing is TRUE, the step is performed
immediately: immediately:
- In the PAUSED state the pipeline loses the PAUSED state, the - In the `PAUSED` state the pipeline loses the `PAUSED` state, the
requested amount of data is skipped and the pipeline prerolls again requested amount of data is skipped and the pipeline prerolls again
when a non-intermediate step completes. When the pipeline was when a non-intermediate step completes. When the pipeline was
stepping while the event is sent, the current step operation is stepping while the event is sent, the current step operation is
updated with the new amount and format. The sink will do a best updated with the new amount and format. The sink will do a best
effort to comply with the new amount. effort to comply with the new amount.
- In the PLAYING state, the pipeline loses the PLAYING state, the - In the PLAYING state, the pipeline loses the `PLAYING` state, the
requested amount of data is skipped (not rendered) from the previous requested amount of data is skipped (not rendered) from the previous
STEP request or from the position of the last PAUSED if no previous STEP request or from the position of the last `PAUSED` if no previous
STEP operation was performed. The pipeline goes back to the PLAYING STEP operation was performed. The pipeline goes back to the `PLAYING`
state when a non-intermediate step completes. state when a non-intermediate step completes.
- When flushing is FALSE, the step will be performed later. - When flushing is FALSE, the step will be performed later.
- In the PAUSED state the step will be done when going to PLAYING. Any - In the `PAUSED` state the step will be done when going to `PLAYING`. Any
previous step operation will be overridden with the new STEP event. previous step operation will be overridden with the new `STEP` event.
- In the PLAYING state the step operation will be performed after the - In the `PLAYING` state the step operation will be performed after the
current step operation completes. If there was no previous step current step operation completes. If there was no previous step
operation, the step operation will be performed from the position of operation, the step operation will be performed from the position of
the last PAUSED state. the last `PAUSED` state.
* **`intermediate`** `G_TYPE_BOOLEAN`: Signal that this step operation is an * **`intermediate`** `G_TYPE_BOOLEAN`: Signal that this step operation is an
intermediate step, part of a series of step operations. It is mostly intermediate step, part of a series of step operations. It is mostly
interesting for stepping in the PAUSED state because the sink will only perform interesting for stepping in the `PAUSED` state because the sink will only perform
a preroll after a non-intermediate step operation completes. Intermediate steps a preroll after a non-intermediate step operation completes. Intermediate steps
are useful to flush out data from other sinks in order to not cause excessive are useful to flush out data from other sinks in order to not cause excessive
queueing. In the PLAYING state the intermediate flag has no visual effect. In queueing. In the PLAYING state the intermediate flag has no visual effect. In
@ -163,7 +163,7 @@ all states, the intermediate flag is passed to the corresponding
`GST_MESSAGE_STEP_DONE`. `GST_MESSAGE_STEP_DONE`.
The application will create a STEP event to start or stop the stepping The application will create a STEP event to start or stop the stepping
operation. Both stepping in PAUSED and PLAYING can be performed by means operation. Both stepping in `PAUSED` and `PLAYING` can be performed by means
of the flush flag. of the flush flag.
The event is usually sent to the pipeline, which will typically The event is usually sent to the pipeline, which will typically