pub struct TagSetter(_, _);
Element interface that allows setting of media metadata.
Elements that support changing a stream's metadata will implement this
interface. Examples of such elements are 'vorbisenc', 'theoraenc' and
'id3v2mux'.
If you just want to retrieve metadata in your application then all you
need to do is watch for tag messages on your pipeline's bus. This
interface is only for setting metadata, not for extracting it. To set tags
from the application, find tagsetter elements and set tags using e.g.
TagSetter::merge_tags
or TagSetter::add_tags
. Also consider
setting the TagMergeMode
that is used for tag events that arrive at the
tagsetter element (default mode is to keep existing tags).
The application should do that before the element goes to State::Paused
.
Elements implementing the TagSetter
interface often have to merge
any tags received from upstream and the tags set by the application via
the interface. This can be done like this:
GstTagMergeMode merge_mode;
const GstTagList *application_tags;
const GstTagList *event_tags;
GstTagSetter *tagsetter;
GstTagList *result;
tagsetter = GST_TAG_SETTER (element);
merge_mode = gst_tag_setter_get_tag_merge_mode (tagsetter);
application_tags = gst_tag_setter_get_tag_list (tagsetter);
event_tags = (const GstTagList *) element->event_tags;
GST_LOG_OBJECT (tagsetter, "merging tags, merge mode = %d", merge_mode);
GST_LOG_OBJECT (tagsetter, "event tags: %" GST_PTR_FORMAT, event_tags);
GST_LOG_OBJECT (tagsetter, "set tags: %" GST_PTR_FORMAT, application_tags);
result = gst_tag_list_merge (application_tags, event_tags, merge_mode);
GST_LOG_OBJECT (tagsetter, "final tags: %" GST_PTR_FORMAT, result);
TagSetterExt
, ElementExt
, GstObjectExt
, glib::object::ObjectExt
Performs copy-assignment from source
. Read more
Feeds this value into the given [Hasher
]. Read more
Feeds a slice of this type into the given [Hasher
]. Read more
This method returns an Ordering
between self
and other
. Read more
fn max(self, other: Self) -> Self | 1.21.0 [src] |
Compares and returns the maximum of two values. Read more
fn min(self, other: Self) -> Self | 1.21.0 [src] |
Compares and returns the minimum of two values. Read more
Returns the type identifier of Self
.
This method tests for self
and other
values to be equal, and is used by ==
. Read more
This method tests for !=
.
This method returns an ordering between self
and other
values if one exists. Read more
This method tests less than (for self
and other
) and is used by the <
operator. Read more
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
This method tests greater than (for self
and other
) and is used by the >
operator. Read more
This method tests greater than or equal to (for self
and other
) and is used by the >=
operator. Read more
Formats the value using the given formatter. Read more