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GStreamer 0.10 Core Reference Manual | ![]() |
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#include <gst/gst.h> GstMiniObject; enum GstMiniObjectFlags; GstMiniObject* (*GstMiniObjectCopyFunction) (const GstMiniObject *obj); void (*GstMiniObjectFinalizeFunction) (GstMiniObject *obj); #define GST_MINI_OBJECT_FLAGS (obj) #define GST_MINI_OBJECT_FLAG_IS_SET (obj,flag) #define GST_MINI_OBJECT_FLAG_SET (obj,flag) #define GST_MINI_OBJECT_FLAG_UNSET (obj,flag) #define GST_MINI_OBJECT_REFCOUNT (obj) #define GST_MINI_OBJECT_REFCOUNT_VALUE (obj) GstMiniObject* gst_mini_object_new (GType type); GstMiniObject* gst_mini_object_copy (const GstMiniObject *mini_object); gboolean gst_mini_object_is_writable (const GstMiniObject *mini_object); GstMiniObject* gst_mini_object_make_writable (GstMiniObject *mini_object); GstMiniObject* gst_mini_object_ref (GstMiniObject *mini_object); void gst_mini_object_unref (GstMiniObject *mini_object); void gst_mini_object_replace (GstMiniObject **olddata, GstMiniObject *newdata); GstParamSpecMiniObject; GParamSpec* gst_param_spec_mini_object (const char *name, const char *nick, const char *blurb, GType object_type, GParamFlags flags); void gst_value_set_mini_object (GValue *value, GstMiniObject *mini_object); void gst_value_take_mini_object (GValue *value, GstMiniObject *mini_object); GstMiniObject* gst_value_get_mini_object (const GValue *value); GstMiniObject* gst_value_dup_mini_object (const GValue *value);
GstMiniObject is a baseclass like GObject, but has been stripped down of features to be fast and small. It offers sub-classing and ref-counting in the same way as GObject does. It has no properties and no signal-support though.
Last reviewed on 2005-11-23 (0.9.5)
typedef struct { GTypeInstance instance; gint refcount; guint flags; } GstMiniObject;
Base class for refcounted lightweight objects.
GTypeInstance instance ; |
type instance |
gint refcount ; |
atomic refcount |
guint flags ; |
extra flags. |
typedef enum { GST_MINI_OBJECT_FLAG_READONLY = (1<<0), /* padding */ GST_MINI_OBJECT_FLAG_LAST = (1<<4) } GstMiniObjectFlags;
Flags for the padtemplate
GstMiniObject* (*GstMiniObjectCopyFunction) (const GstMiniObject *obj);
Virtual function prototype for methods to create copies of instances.
obj : |
MiniObject to copy |
Returns : | reference to cloned instance. |
void (*GstMiniObjectFinalizeFunction) (GstMiniObject *obj);
Virtual function prototype for methods to free ressources used by
mini-objects. Subclasses of the mini object are allowed to revive the
passed object by doing a gst_mini_object_ref()
. If the object is not
revived after the finalize function, the memory associated with the
object is freed.
obj : |
MiniObject to finalize |
#define GST_MINI_OBJECT_FLAGS(obj) (GST_MINI_OBJECT_CAST(obj)->flags)
This macro returns the entire set of flags for the mini-object.
obj : |
MiniObject to return flags for. |
#define GST_MINI_OBJECT_FLAG_IS_SET(obj,flag) !!(GST_MINI_OBJECT_FLAGS (obj) & (flag))
This macro checks to see if the given flag is set.
obj : |
MiniObject to check for flags. |
flag : |
Flag to check for |
#define GST_MINI_OBJECT_FLAG_SET(obj,flag) (GST_MINI_OBJECT_FLAGS (obj) |= (flag))
This macro sets the given bits.
obj : |
MiniObject to set flag in. |
flag : |
Flag to set, can by any number of bits in guint32. |
#define GST_MINI_OBJECT_FLAG_UNSET(obj,flag) (GST_MINI_OBJECT_FLAGS (obj) &= ~(flag))
This macro usets the given bits.
obj : |
MiniObject to unset flag in. |
flag : |
Flag to set, must be a single bit in guint32. |
#define GST_MINI_OBJECT_REFCOUNT(obj) ((GST_MINI_OBJECT_CAST(obj))->refcount)
Get access to the reference count field of the mini-object.
obj : |
a GstMiniObject |
#define GST_MINI_OBJECT_REFCOUNT_VALUE(obj) (g_atomic_int_get (&(GST_MINI_OBJECT_CAST(obj))->refcount))
Get the reference count value of the mini-object.
obj : |
a GstMiniObject |
GstMiniObject* gst_mini_object_new (GType type);
Creates a new mini-object of the desired type.
MT safe
type : |
the GType of the mini-object to create |
Returns : | the new mini-object. |
GstMiniObject* gst_mini_object_copy (const GstMiniObject *mini_object);
Creates a copy of the mini-object.
MT safe
mini_object : |
the mini-object to copy |
Returns : | the new mini-object. |
gboolean gst_mini_object_is_writable (const GstMiniObject *mini_object);
Checks if a mini-object is writable. A mini-object is writable if the reference count is one and the GST_MINI_OBJECT_FLAG_READONLY flag is not set. Modification of a mini-object should only be done after verifying that it is writable.
MT safe
mini_object : |
the mini-object to check |
Returns : | TRUE if the object is writable. |
GstMiniObject* gst_mini_object_make_writable (GstMiniObject *mini_object);
Checks if a mini-object is writable. If not, a writable copy is made and returned. This gives away the reference to the original mini object, and returns a reference to the new object.
MT safe
mini_object : |
the mini-object to make writable |
Returns : | a mini-object (possibly the same pointer) that is writable. |
GstMiniObject* gst_mini_object_ref (GstMiniObject *mini_object);
Increase the reference count of the mini-object.
Note that the refcount affects the writeability
of mini
-object, see gst_mini_object_is_writable()
. It is
important to note that keeping additional references to
GstMiniObject instances can potentially increase the number
of memcpy operations in a pipeline, especially if the miniobject
is a GstBuffer.
mini_object : |
the mini-object |
Returns : | the mini-object. |
void gst_mini_object_unref (GstMiniObject *mini_object);
Decreases the reference count of the mini-object, possibly freeing the mini-object.
mini_object : |
the mini-object |
void gst_mini_object_replace (GstMiniObject **olddata, GstMiniObject *newdata);
Modifies a pointer to point to a new mini-object. The modification
is done atomically, and the reference counts are updated correctly.
Either newdata
and the value pointed to by olddata
may be NULL.
olddata : |
pointer to a pointer to a mini-object to be replaced |
newdata : |
pointer to new mini-object |
typedef struct { GParamSpec parent_instance; } GstParamSpecMiniObject;
A GParamSpec
derived structure that contains the meta data
for GstMiniObject
properties.
GParamSpec parent_instance ; |
private GParamSpec portion
|
GParamSpec* gst_param_spec_mini_object (const char *name, const char *nick, const char *blurb, GType object_type, GParamFlags flags);
Creates a new GParamSpec instance that hold GstMiniObject references.
name : |
the canonical name of the property |
nick : |
the nickname of the property |
blurb : |
a short description of the property |
object_type : |
the GstMiniObjectType for the property |
flags : |
a combination of GParamFlags |
Returns : | a newly allocated GParamSpec instance |
void gst_value_set_mini_object (GValue *value, GstMiniObject *mini_object);
Set the contents of a GST_TYPE_MINI_OBJECT
derived GValue to
mini_object
.
The caller retains ownership of the reference.
value : |
a valid GValue of GST_TYPE_MINI_OBJECT derived type
|
mini_object : |
mini object value to set |
void gst_value_take_mini_object (GValue *value, GstMiniObject *mini_object);
Set the contents of a GST_TYPE_MINI_OBJECT
derived GValue to
mini_object
.
Takes over the ownership of the caller's reference to mini_object
;
the caller doesn't have to unref it any more.
value : |
a valid GValue of GST_TYPE_MINI_OBJECT derived type
|
mini_object : |
mini object value to take |
GstMiniObject* gst_value_get_mini_object (const GValue *value);
Get the contents of a GST_TYPE_MINI_OBJECT
derived GValue.
Does not increase the refcount of the returned object.
value : |
a valid GValue of GST_TYPE_MINI_OBJECT derived type
|
Returns : | mini object contents of value
|
GstMiniObject* gst_value_dup_mini_object (const GValue *value);
Get the contents of a GST_TYPE_MINI_OBJECT
derived GValue,
increasing its reference count.
value : |
a valid GValue of GST_TYPE_MINI_OBJECT derived type
|
Returns : | mini object contents of value
|
Since 0.10.20