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>4.3. Explicit caps</A
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> Obviously, many elements will not need this complex mechanism, because they
are much simpler than that. They only support one format, or their format
is fixed but the contents of the format depend on the stream or something
else. In those cases, <SPAN
CLASS="emphasis"
><I
CLASS="emphasis"
>explicit caps</I
></SPAN
> are an easy way
of handling caps. Explicit caps are an easy way of specifying one, fixed,
supported format on a pad. Pads using explicit caps do not implement their
own <CODE
CLASS="function"
>_getcaps ()</CODE
> or <CODE
CLASS="function"
>_link ()</CODE
>
functions. When the exact format is known, an elements uses
<CODE
CLASS="function"
>gst_pad_set_explicit_caps ()</CODE
> to specify the exact
format. This is very useful for demuxers, for example.
</P
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> static void
gst_my_filter_init (GstMyFilter *filter)
{
GstElementClass *klass = GST_ELEMENT_GET_CLASS (filter);
[..]
filter->srcpad = gst_pad_new_from_template (
gst_element_class_get_pad_template (klass, "src"), "src");
gst_pad_use_explicit_caps (filter->srcpad);
[..]
}
static void
gst_my_filter_somefunction (GstMyFilter *filter)
{
GstCaps *caps = ..;
[..]
gst_pad_set_explicit_caps (filter->srcpad, caps);
[..]
}
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