design: caps: add missing markup

This commit is contained in:
Reynaldo H. Verdejo Pinochet 2017-02-02 15:34:55 -08:00
parent 400e4e5a11
commit 1687511e4e

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@ -8,7 +8,7 @@ Caps are exposed on `GstPadTemplates` to describe all possible types a
given pad can handle. They are also stored in the registry along with a
description of the element.
Caps are exposed on the element pads via CAPS and `ACCEPT_CAPS` queries.
Caps are exposed on the element pads via `CAPS` and `ACCEPT_CAPS` queries.
This function describes the possible types that the pad can handle or
produce ([negotiation](design/negotiation.md)).
@ -49,8 +49,8 @@ This is different to the intuitive mathematical definition as an empty field
is defined to contain all possible values. This means that the empty field is
always a superset of any other field.
EMPTY caps are a subset of every other caps. Every caps are a subset of
ANY caps.
`EMPTY` caps are a subset of every other caps. Every caps are a subset of
`ANY` caps.
### Equality
@ -71,8 +71,8 @@ empty. If one structure contains a field that is not existing in the
other structure it will be copied over to the intersection with the same
value.
The intersection with ANY caps is always the other caps and the
intersection with EMPTY caps is always EMPTY.
The intersection with `ANY` caps is always the other caps and the
intersection with `EMPTY` caps is always `EMPTY`.
### Union
@ -110,7 +110,7 @@ structure add additional constraints and/or information about the media
type, like the width and height of a video frame, or the codec profile
that is used. These fields can be non-fixed (e.g. ranges) for non-fixed
caps but must be fixated to a fixed value during negotiation. If a field
is included in the caps returned by a pad via the CAPS query, it imposes
is included in the caps returned by a pad via the `CAPS` query, it imposes
an additional constraint during negotiation. The caps in the end must
have this field with a value that is a subset of the non-fixed value.
Additional fields that are added in the negotiated caps give additional
@ -124,10 +124,10 @@ specific structure, and only structures with the same name *and* equal
caps features are considered compatible. Caps features can be used to
require a specific memory representation or a specific meta to be set on
buffers, for example a pad could require for a specific structure that
it is passed EGLImage memory or buffers with the video meta. If no caps
it is passed `EGLImage` memory or buffers with the video meta. If no caps
features are provided for a structure, it is assumed that system memory
is required unless later negotiation steps (e.g. the ALLOCATION query)
detect that something else can be used. The special ANY caps features
is required unless later negotiation steps (e.g. the `ALLOCATION` query)
detect that something else can be used. The special `ANY` caps features
can be used to specify that any caps feature would be accepted, for
example if the buffer memory is not touched at all.
@ -142,4 +142,4 @@ pads caps but pads can introduce additional constraints which would
be checked in the `ACCEPT_CAPS` query handler.
Data flow can only happen after pads have decided on common fixed caps.
These caps are distributed to both pads with the CAPS event.
These caps are distributed to both pads with the `CAPS` event.