GstIndex

GStreamer Core Reference Manual
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struct GstIndexEntry

struct GstIndexEntry {
  GstIndexEntryType	 type;
  gint			 id;

  union {
    struct {
      gchar		*description;
    } id;
    struct {
      gint		 nassocs;
      GstIndexAssociation 
	      		*assocs;
      GstAssocFlags	 flags;
    } assoc;
    struct {
      gchar		*key;
      GType		 type;
      gpointer		 object;
    } object;
    struct {
      GstFormat		 format;
      gchar		*key;
    } format;
  } data;
};

The basic element of an index.

struct GstIndexGroup

struct GstIndexGroup {
  /* unique ID of group in index */
  gint groupnum;

  /* list of entries */
  GList *entries;

  /* the certainty level of the group */
  GstIndexCertainty certainty;

  /* peer group that contains more certain entries */
  gint peergroup;
};

A group of related entries in an index.

enum GstIndexCertainty

typedef enum {
  GST_INDEX_UNKNOWN,
  GST_INDEX_CERTAIN,
  GST_INDEX_FUZZY
} GstIndexCertainty;

The certainty of a group in the index.

`GST_INDEX_UNKNOWN`	accuracy is not known
`GST_INDEX_CERTAIN`	accuracy is perfect
`GST_INDEX_FUZZY`	accuracy is fuzzy

enum GstIndexEntryType

typedef enum {
  GST_INDEX_ENTRY_ID,
  GST_INDEX_ENTRY_ASSOCIATION,
  GST_INDEX_ENTRY_OBJECT,
  GST_INDEX_ENTRY_FORMAT,
} GstIndexEntryType;

The different types of entries in the index.

`GST_INDEX_ENTRY_ID`	This entry is an id that maps an index id to its owner object
`GST_INDEX_ENTRY_ASSOCIATION`	This entry is an association between formats
`GST_INDEX_ENTRY_OBJECT`	An object
`GST_INDEX_ENTRY_FORMAT`	A format definition

enum GstIndexLookupMethod

typedef enum {
  GST_INDEX_LOOKUP_EXACT,
  GST_INDEX_LOOKUP_BEFORE,
  GST_INDEX_LOOKUP_AFTER,
} GstIndexLookupMethod;

Specify the method to find an index entry in the index.

`GST_INDEX_LOOKUP_EXACT`	There has to be an exact indexentry with the given format/value
`GST_INDEX_LOOKUP_BEFORE`	The exact entry or the one before it
`GST_INDEX_LOOKUP_AFTER`	The exact entry or the one after it

GST_INDEX_NASSOCS()

#define GST_INDEX_NASSOCS(entry)		((entry)->data.assoc.nassocs)

Get the number of associations in the entry.

entry :

The entry to query

GST_INDEX_ASSOC_FLAGS()

#define GST_INDEX_ASSOC_FLAGS(entry)		((entry)->data.assoc.flags)

Get the flags for this entry

entry :

The entry to query

GST_INDEX_ASSOC_FORMAT()

#define GST_INDEX_ASSOC_FORMAT(entry,i)		((entry)->data.assoc.assocs[(i)].format)

Get the i-th format of the entry.

`entry` :	The entry to query
`i` :	The format index

GST_INDEX_ASSOC_VALUE()

#define GST_INDEX_ASSOC_VALUE(entry,i)		((entry)->data.assoc.assocs[(i)].value)

Get the i-th value of the entry.

`entry` :	The entry to query
`i` :	The value index

struct GstIndexAssociation

struct GstIndexAssociation {
  GstFormat 	format;
  gint64 	value;
};

An association in an entry.

GstFormat `format`	the format of the association
gint64 `value`	the value of the association

enum GstAssocFlags

typedef enum {
  GST_ASSOCIATION_FLAG_NONE 	= 0,
  GST_ASSOCIATION_FLAG_KEY_UNIT = (1 << 0),

  /* new flags should start here */
  GST_ASSOCIATION_FLAG_LAST	= (1 << 8),
} GstAssocFlags;

flags for an association entry

`GST_ASSOCIATION_FLAG_NONE`	no extra flags
`GST_ASSOCIATION_FLAG_KEY_UNIT`	the entry marks a key unit, a key unit is one that marks a place where one can randomly seek to.
`GST_ASSOCIATION_FLAG_LAST`	extra user defined flags should start here.

GST_INDEX_FORMAT_FORMAT()

#define GST_INDEX_FORMAT_FORMAT(entry)		((entry)->data.format.format)

Get the format of the format entry

entry :

The entry to query

GST_INDEX_FORMAT_KEY()

#define GST_INDEX_FORMAT_KEY(entry)		((entry)->data.format.key)

Get the key of the format entry

entry :

The entry to query

GST_INDEX_ID_DESCRIPTION()

#define GST_INDEX_ID_DESCRIPTION(entry)		((entry)->data.id.description)

Get the description of the id entry

entry :

The entry to query

GstIndexFilter ()

gboolean    (*GstIndexFilter)               (GstIndex *index,
                                             GstIndexEntry *entry);

Function to filter out entries in the index.

`index` :	The index being queried
`entry` :	The entry to be added.
Returns :	This function should return TRUE if the entry is to be added to the index, FALSE otherwise.

GstIndexResolver ()

gboolean    (*GstIndexResolver)             (GstIndex *index,
                                             GstObject *writer,
                                             gchar **writer_string,
                                             gpointer user_data);

Function to resolve ids to writer descriptions.

`index` :	the index being queried.
`writer` :	The object that wants to write
`writer_string` :	A description of the writer.
`user_data` :	user_data as registered
Returns :	TRUE if an id could be assigned to the writer.

struct GstIndex

struct GstIndex;

The GstIndex object

gst_index_new ()

GstIndex*   gst_index_new                   (void);

Create a new tileindex object

Returns :

a new index object

gst_index_get_group ()

gint        gst_index_get_group             (GstIndex *index);

Get the id of the current group.

`index` :	the index to get the current group from
Returns :	the id of the current group.

gst_index_new_group ()

gint        gst_index_new_group             (GstIndex *index);

Create a new group for the given index. It will be set as the current group.

`index` :	the index to create the new group in
Returns :	the id of the newly created group.

gst_index_set_group ()

gboolean    gst_index_set_group             (GstIndex *index,
                                             gint groupnum);

Set the current groupnumber to the given argument.

`index` :	the index to set the new group in
`groupnum` :	the groupnumber to set
Returns :	TRUE if the operation succeeded, FALSE if the group did not exist.

gst_index_set_certainty ()

void        gst_index_set_certainty         (GstIndex *index,
                                             GstIndexCertainty certainty);

Set the certainty of the given index.

`index` :	the index to set the certainty on
`certainty` :	the certainty to set

gst_index_get_certainty ()

GstIndexCertainty gst_index_get_certainty   (GstIndex *index);

Get the certainty of the given index.

`index` :	the index to get the certainty of
Returns :	the certainty of the index.

gst_index_set_filter ()

void        gst_index_set_filter            (GstIndex *index,
                                             GstIndexFilter filter,
                                             gpointer user_data);

Lets the app register a custom filter function so that it can select what entries should be stored in the index.

`index` :	the index to register the filter on
`filter` :	the filter to register
`user_data` :	data passed to the filter function

gst_index_set_resolver ()

void        gst_index_set_resolver          (GstIndex *index,
                                             GstIndexResolver resolver,
                                             gpointer user_data);

Lets the app register a custom function to map index ids to writer descriptions.

`index` :	the index to register the resolver on
`resolver` :	the resolver to register
`user_data` :	data passed to the resolver function

gst_index_get_writer_id ()

gboolean    gst_index_get_writer_id         (GstIndex *index,
                                             GstObject *writer,
                                             gint *id);

Before entries can be added to the index, a writer should obtain a unique id. The methods to add new entries to the index require this id as an argument.

The application can implement a custom function to map the writer object to a string. That string will be used to register or look up an id in the index.

`index` :	the index to get a unique write id for
`writer` :	the GstObject to allocate an id for
`id` :	a pointer to a gint to hold the id
Returns :	TRUE if the writer would be mapped to an id.

gst_index_add_format ()

GstIndexEntry* gst_index_add_format         (GstIndex *index,
                                             gint id,
                                             GstFormat format);

Adds a format entry into the index. This function is used to map dynamic GstFormat ids to their original format key.

`index` :	the index to add the entry to
`id` :	the id of the index writer
`format` :	the format to add to the index
Returns :	a pointer to the newly added entry in the index.

gst_index_add_association ()

GstIndexEntry* gst_index_add_association    (GstIndex *index,
                                             gint id,
                                             GstAssocFlags flags,
                                             GstFormat format,
                                             gint64 value,
                                             ...);

Associate given format/value pairs with eachother. Be sure to pass gint64 values to this functions varargs, you might want to use a gint64 cast to be sure.

`index` :	the index to add the entry to
`id` :	the id of the index writer
`flags` :	optinal flags for this entry
`format` :	the format of the value
`value` :	the value
`...` :	other format/value pairs or 0 to end the list
Returns :	a pointer to the newly added entry in the index.

gst_index_add_object ()

GstIndexEntry* gst_index_add_object         (GstIndex *index,
                                             gint id,
                                             gchar *key,
                                             GType type,
                                             gpointer object);

Add the given object to the index with the given key.

`index` :	the index to add the object to
`id` :	the id of the index writer
`key` :	a key for the object
`type` :	the GType of the object
`object` :	a pointer to the object to add
Returns :	a pointer to the newly added entry in the index.

gst_index_add_id ()

GstIndexEntry* gst_index_add_id             (GstIndex *index,
                                             gint id,
                                             gchar *description);

Add an id entry into the index.

`index` :	the index to add the entry to
`id` :	the id of the index writer
`description` :	the description of the index writer
Returns :	a pointer to the newly added entry in the index.

gst_index_get_assoc_entry ()

GstIndexEntry* gst_index_get_assoc_entry    (GstIndex *index,
                                             gint id,
                                             GstIndexLookupMethod method,
                                             GstAssocFlags flags,
                                             GstFormat format,
                                             gint64 value);

Finds the given format/value in the index

`index` :	the index to search
`id` :	the id of the index writer
`method` :	The lookup method to use
`flags` :	Flags for the entry
`format` :	the format of the value
`value` :	the value to find
Returns :	the entry associated with the value or NULL if the value was not found.

gst_index_get_assoc_entry_full ()

GstIndexEntry* gst_index_get_assoc_entry_full
                                            (GstIndex *index,
                                             gint id,
                                             GstIndexLookupMethod method,
                                             GstAssocFlags flags,
                                             GstFormat format,
                                             gint64 value,
                                             GCompareDataFunc func,
                                             gpointer user_data);

Finds the given format/value in the index with the given compare function and user_data.

`index` :	the index to search
`id` :	the id of the index writer
`method` :	The lookup method to use
`flags` :	Flags for the entry
`format` :	the format of the value
`value` :	the value to find
`func` :	the function used to compare entries
`user_data` :	user data passed to the compare function
Returns :	the entry associated with the value or NULL if the value was not found.

gst_index_entry_free ()

void        gst_index_entry_free            (GstIndexEntry *entry);

Free the memory used by the given entry.

entry :

the entry to free

gst_index_entry_assoc_map ()

gboolean    gst_index_entry_assoc_map       (GstIndexEntry *entry,
                                             GstFormat format,
                                             gint64 *value);

Gets alternative formats associated with the indexentry.

`entry` :	the index to search
`format` :	the format of the value the find
`value` :	a pointer to store the value
Returns :	TRUE if there was a value associated with the given format.

`gstindex` :	the object which received the signal.
`arg1` :	The entry added to the index.
`user_data` :	user data set when the signal handler was connected.

GstIndex

Name

Synopsis

Object Hierarchy

Properties

Signal Prototypes

Description

Details

struct GstIndexEntry

struct GstIndexGroup

enum GstIndexCertainty

enum GstIndexEntryType

enum GstIndexLookupMethod

GST_INDEX_NASSOCS()

GST_INDEX_ASSOC_FLAGS()

GST_INDEX_ASSOC_FORMAT()

GST_INDEX_ASSOC_VALUE()

struct GstIndexAssociation

enum GstAssocFlags

GST_INDEX_FORMAT_FORMAT()

GST_INDEX_FORMAT_KEY()

GST_INDEX_ID_DESCRIPTION()

GstIndexFilter ()

GstIndexResolver ()

struct GstIndex

gst_index_new ()

gst_index_get_group ()

gst_index_new_group ()

gst_index_set_group ()

gst_index_set_certainty ()

gst_index_get_certainty ()

gst_index_set_filter ()

gst_index_set_resolver ()

gst_index_get_writer_id ()

gst_index_add_format ()

gst_index_add_association ()

gst_index_add_object ()

gst_index_add_id ()

gst_index_get_assoc_entry ()

gst_index_get_assoc_entry_full ()

gst_index_entry_free ()

gst_index_entry_assoc_map ()

Properties

Signals

The "entry-added" signal

See Also