GST_QUERY_TYPE_NAME()

#define GST_QUERY_TYPE_NAME(query) (gst_query_type_get_name(GST_QUERY_TYPE(query)))

Get a constant string representation of the GstQueryType of the query.

Since: 0.10.4

gst_query_type_get_name ()

const gchar *
gst_query_type_get_name (GstQueryType query);

Get a printable name for the given query type. Do not modify or free.

gst_query_type_to_quark ()

GQuark
gst_query_type_to_quark (GstQueryType query);

Get the unique quark for the given query type.

gst_query_type_register ()

GstQueryType
gst_query_type_register (const gchar *nick,
                         const gchar *description);

Create a new GstQueryType based on the nick or return an already registered query with that nick

gst_query_type_get_by_nick ()

GstQueryType
gst_query_type_get_by_nick (const gchar *nick);

Get the query type registered with nick .

gst_query_types_contains ()

gboolean
gst_query_types_contains (const GstQueryType *types,
                          GstQueryType type);

See if the given GstQueryType is inside the types query types array.

gst_query_type_get_details ()

const GstQueryTypeDefinition *
gst_query_type_get_details (GstQueryType type);

Get details about the given GstQueryType.

gst_query_type_iterate_definitions ()

GstIterator *
gst_query_type_iterate_definitions (void);

Get a GstIterator of all the registered query types. The definitions iterated over are read only.

Free-function: gst_iterator_free

gst_query_ref ()

GstQuery *
gst_query_ref (GstQuery *q);

Increases the refcount of the given query by one.

gst_query_unref ()

void
gst_query_unref (GstQuery *q);

Decreases the refcount of the query. If the refcount reaches 0, the query will be freed.

gst_query_copy ()

GstQuery *
gst_query_copy (const GstQuery *q);

Copies the given query using the copy function of the parent GstStructure.

Free-function: gst_query_unref

gst_query_make_writable()

#define         gst_query_make_writable(q)      GST_QUERY_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (q)))

Makes a writable query from the given query.

gst_query_new_application ()

GstQuery *
gst_query_new_application (GstQueryType type,
                           GstStructure *structure);

Constructs a new custom application query object. Use gst_query_unref() when done with it.

Free-function: gst_query_unref

gst_query_get_structure ()

GstStructure *
gst_query_get_structure (GstQuery *query);

Get the structure of a query.

gst_query_new_convert ()

GstQuery *
gst_query_new_convert (GstFormat src_format,
                       gint64 value,
                       GstFormat dest_format);

Constructs a new convert query object. Use gst_query_unref() when done with it. A convert query is used to ask for a conversion between one format and another.

Free-function: gst_query_unref

gst_query_set_convert ()

void
gst_query_set_convert (GstQuery *query,
                       GstFormat src_format,
                       gint64 src_value,
                       GstFormat dest_format,
                       gint64 dest_value);

Answer a convert query by setting the requested values.

gst_query_parse_convert ()

void
gst_query_parse_convert (GstQuery *query,
                         GstFormat *src_format,
                         gint64 *src_value,
                         GstFormat *dest_format,
                         gint64 *dest_value);

Parse a convert query answer. Any of src_format , src_value , dest_format , and dest_value may be NULL, in which case that value is omitted.

gst_query_new_position ()

GstQuery *
gst_query_new_position (GstFormat format);

Constructs a new query stream position query object. Use gst_query_unref() when done with it. A position query is used to query the current position of playback in the streams, in some format.

Free-function: gst_query_unref

gst_query_set_position ()

void
gst_query_set_position (GstQuery *query,
                        GstFormat format,
                        gint64 cur);

Answer a position query by setting the requested value in the given format.

gst_query_parse_position ()

void
gst_query_parse_position (GstQuery *query,
                          GstFormat *format,
                          gint64 *cur);

Parse a position query, writing the format into format , and the position into cur , if the respective parameters are non-NULL.

gst_query_new_duration ()

GstQuery *
gst_query_new_duration (GstFormat format);

Constructs a new stream duration query object to query in the given format. Use gst_query_unref() when done with it. A duration query will give the total length of the stream.

Free-function: gst_query_unref

gst_query_set_duration ()

void
gst_query_set_duration (GstQuery *query,
                        GstFormat format,
                        gint64 duration);

Answer a duration query by setting the requested value in the given format.

gst_query_parse_duration ()

void
gst_query_parse_duration (GstQuery *query,
                          GstFormat *format,
                          gint64 *duration);

Parse a duration query answer. Write the format of the duration into format , and the value into duration , if the respective variables are non-NULL.

gst_query_new_latency ()

GstQuery *
gst_query_new_latency (void);

Constructs a new latency query object. Use gst_query_unref() when done with it. A latency query is usually performed by sinks to compensate for additional latency introduced by elements in the pipeline.

Free-function: gst_query_unref

Since: 0.10.12

gst_query_parse_latency ()

void
gst_query_parse_latency (GstQuery *query,
                         gboolean *live,
                         GstClockTime *min_latency,
                         GstClockTime *max_latency);

Parse a latency query answer.

Since: 0.10.12

gst_query_set_latency ()

void
gst_query_set_latency (GstQuery *query,
                       gboolean live,
                       GstClockTime min_latency,
                       GstClockTime max_latency);

Answer a latency query by setting the requested values in the given format.

Since: 0.10.12

gst_query_new_seeking ()

GstQuery *
gst_query_new_seeking (GstFormat format);

Constructs a new query object for querying seeking properties of the stream.

Free-function: gst_query_unref

gst_query_set_seeking ()

void
gst_query_set_seeking (GstQuery *query,
                       GstFormat format,
                       gboolean seekable,
                       gint64 segment_start,
                       gint64 segment_end);

Set the seeking query result fields in query .

gst_query_parse_seeking ()

void
gst_query_parse_seeking (GstQuery *query,
                         GstFormat *format,
                         gboolean *seekable,
                         gint64 *segment_start,
                         gint64 *segment_end);

Parse a seeking query, writing the format into format , and other results into the passed parameters, if the respective parameters are non-NULL

gst_query_new_formats ()

GstQuery *
gst_query_new_formats (void);

Constructs a new query object for querying formats of the stream.

Free-function: gst_query_unref

Since: 0.10.4

gst_query_set_formats ()

void
gst_query_set_formats (GstQuery *query,
                       gint n_formats,
                       ...);

Set the formats query result fields in query . The number of formats passed must be equal to n_formats .

gst_query_set_formatsv ()

void
gst_query_set_formatsv (GstQuery *query,
                        gint n_formats,
                        const GstFormat *formats);

Set the formats query result fields in query . The number of formats passed in the formats array must be equal to n_formats .

Since: 0.10.4

gst_query_parse_formats_length ()

void
gst_query_parse_formats_length (GstQuery *query,
                                guint *n_formats);

Parse the number of formats in the formats query .

Since: 0.10.4

gst_query_parse_formats_nth ()

void
gst_query_parse_formats_nth (GstQuery *query,
                             guint nth,
                             GstFormat *format);

Parse the format query and retrieve the nth format from it into format . If the list contains less elements than nth , format will be set to GST_FORMAT_UNDEFINED.

Since: 0.10.4

gst_query_new_segment ()

GstQuery *
gst_query_new_segment (GstFormat format);

Constructs a new segment query object. Use gst_query_unref() when done with it. A segment query is used to discover information about the currently configured segment for playback.

Free-function: gst_query_unref

gst_query_set_segment ()

void
gst_query_set_segment (GstQuery *query,
                       gdouble rate,
                       GstFormat format,
                       gint64 start_value,
                       gint64 stop_value);

Answer a segment query by setting the requested values. The normal playback segment of a pipeline is 0 to duration at the default rate of 1.0. If a seek was performed on the pipeline to play a different segment, this query will return the range specified in the last seek.

start_value and stop_value will respectively contain the configured playback range start and stop values expressed in format . The values are always between 0 and the duration of the media and start_value <= stop_value . rate will contain the playback rate. For negative rates, playback will actually happen from stop_value to start_value .

gst_query_parse_segment ()

void
gst_query_parse_segment (GstQuery *query,
                         gdouble *rate,
                         GstFormat *format,
                         gint64 *start_value,
                         gint64 *stop_value);

Parse a segment query answer. Any of rate , format , start_value , and stop_value may be NULL, which will cause this value to be omitted.

See gst_query_set_segment() for an explanation of the function arguments.

gst_query_new_buffering ()

GstQuery *
gst_query_new_buffering (GstFormat format);

Constructs a new query object for querying the buffering status of a stream.

Free-function: gst_query_new

Since: 0.10.20

gst_query_set_buffering_percent ()

void
gst_query_set_buffering_percent (GstQuery *query,
                                 gboolean busy,
                                 gint percent);

Set the percentage of buffered data. This is a value between 0 and 100. The busy indicator is TRUE when the buffering is in progress.

Since: 0.10.20

gst_query_parse_buffering_percent ()

void
gst_query_parse_buffering_percent (GstQuery *query,
                                   gboolean *busy,
                                   gint *percent);

Get the percentage of buffered data. This is a value between 0 and 100. The busy indicator is TRUE when the buffering is in progress.

Since: 0.10.20

gst_query_set_buffering_stats ()

void
gst_query_set_buffering_stats (GstQuery *query,
                               GstBufferingMode mode,
                               gint avg_in,
                               gint avg_out,
                               gint64 buffering_left);

Configures the buffering stats values in query .

Since: 0.10.20

gst_query_parse_buffering_stats ()

void
gst_query_parse_buffering_stats (GstQuery *query,
                                 GstBufferingMode *mode,
                                 gint *avg_in,
                                 gint *avg_out,
                                 gint64 *buffering_left);

Extracts the buffering stats values from query .

Since: 0.10.20

gst_query_set_buffering_range ()

void
gst_query_set_buffering_range (GstQuery *query,
                               GstFormat format,
                               gint64 start,
                               gint64 stop,
                               gint64 estimated_total);

Set the available query result fields in query .

Since: 0.10.20

gst_query_parse_buffering_range ()

void
gst_query_parse_buffering_range (GstQuery *query,
                                 GstFormat *format,
                                 gint64 *start,
                                 gint64 *stop,
                                 gint64 *estimated_total);

Parse an available query, writing the format into format , and other results into the passed parameters, if the respective parameters are non-NULL

Since: 0.10.20

gst_query_add_buffering_range ()

gboolean
gst_query_add_buffering_range (GstQuery *query,
                               gint64 start,
                               gint64 stop);

Set the buffering-ranges array field in query . The current last start position of the array should be inferior to start .

Since: 0.10.31

gst_query_get_n_buffering_ranges ()

guint
gst_query_get_n_buffering_ranges (GstQuery *query);

Retrieve the number of values currently stored in the buffered-ranges array of the query's structure.

Since: 0.10.31

gst_query_parse_nth_buffering_range ()

gboolean
gst_query_parse_nth_buffering_range (GstQuery *query,
                                     guint index,
                                     gint64 *start,
                                     gint64 *stop);

Parse an available query and get the start and stop values stored at the index of the buffered ranges array.

Since: 0.10.31

gst_query_new_uri ()

GstQuery *
gst_query_new_uri (void);

Constructs a new query URI query object. Use gst_query_unref() when done with it. An URI query is used to query the current URI that is used by the source or sink.

Free-function: gst_query_unref

Since: 0.10.22

gst_query_parse_uri ()

void
gst_query_parse_uri (GstQuery *query,
                     gchar **uri);

Parse an URI query, writing the URI into uri as a newly allocated string, if the respective parameters are non-NULL. Free the string with g_free() after usage.

Since: 0.10.22

gst_query_set_uri ()

void
gst_query_set_uri (GstQuery *query,
                   const gchar *uri);

Answer a URI query by setting the requested URI.

Since: 0.10.22

struct GstQuery

struct GstQuery {
  GstMiniObject mini_object;

  GstQueryType type;

  GstStructure *structure;
};

The GstQuery structure.

enum GstQueryType

Standard predefined Query types

struct GstQueryTypeDefinition

struct GstQueryTypeDefinition {
  GstQueryType   value;
  const gchar   *nick;
  const gchar   *description;
  GQuark         quark;
};

A Query Type definition

enum GstBufferingMode

The different types of buffering methods.