|  |  |  | GStreamer 0.10 Core Reference Manual |  | 
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| GstUtilsGstUtils — Various utility functions | 
#include <gst/gst.h> #define GST_BOILERPLATE_WITH_INTERFACE (type, type_as_function, \ parent_type, parent_type_as_macro, interface_type, \ interface_type_as_macro, interface_as_function) #define GST_BOILERPLATE_FULL (type, type_as_function, parent_type, parent_type_macro, additional_initializations) #define GST_BOILERPLATE (type,type_as_function,parent_type,parent_type_macro) #define GST_CALL_PARENT (parent_class_cast, name, args) #define GST_CALL_PARENT_WITH_DEFAULT (parent_class_cast, name, args, def_return) #define GST_READ_UINT8 (data) #define GST_READ_UINT16_LE (data) #define GST_READ_UINT16_BE (data) #define GST_READ_UINT32_LE (data) #define GST_READ_UINT32_BE (data) #define GST_READ_UINT64_LE (data) #define GST_READ_UINT64_BE (data) #define GST_WRITE_UINT8 (data, num) #define GST_WRITE_UINT16_LE (data, num) #define GST_WRITE_UINT16_BE (data, num) #define GST_WRITE_UINT32_LE (data, num) #define GST_WRITE_UINT32_BE (data, num) #define GST_WRITE_UINT64_LE (data, num) #define GST_WRITE_UINT64_BE (data, num) #define GST_ROUND_UP_2 (num) #define GST_ROUND_UP_4 (num) #define GST_ROUND_UP_8 (num) #define GST_ROUND_UP_16 (num) #define GST_ROUND_UP_32 (num) #define GST_ROUND_UP_64 (num) void gst_atomic_int_set (gint *atomic_int, gint value); const gchar* gst_flow_get_name (GstFlowReturn ret); GQuark gst_flow_to_quark (GstFlowReturn ret); void gst_print_element_args (GString *buf, gint indent, GstElement *element); void gst_print_pad_caps (GString *buf, gint indent, GstPad *pad); #define gst_guint64_to_gdouble (value) #define gst_gdouble_to_guint64 (value) void gst_util_dump_mem (const guchar *mem, guint size); guint64 gst_util_uint64_scale (guint64 val, guint64 num, guint64 denom); guint64 gst_util_uint64_scale_int (guint64 val, gint num, gint denom); void gst_util_set_object_arg (GObject *object, const gchar *name, const gchar *value); void gst_util_set_value_from_string (GValue *value, const gchar *value_str);
#define     GST_BOILERPLATE_WITH_INTERFACE(type, type_as_function,		\
    parent_type, parent_type_as_macro, interface_type,			\
    interface_type_as_macro, interface_as_function)
Like GST_BOILERPLATE, but makes the type 1) implement an interface, and 2) implement GstImplementsInterface for that type.
After this you will need to implement interface_as_function ## _supported and interface_as_function ## _interface_init
| type: | the name of the type struct | 
| type_as_function: | the prefix for the functions | 
| parent_type_as_macro: | the parent type macro | 
| interface_type: | the name of the interface type struct | 
| interface_as_function: | the interface function name prefix | 
#define GST_BOILERPLATE_FULL(type, type_as_function, parent_type, parent_type_macro, additional_initializations)
Define the boilerplate type stuff to reduce typos and code size. Defines the get_type method and the parent_class static variable.
GST_BOILERPLATE_FULL (GstFdSink, gst_fdsink, GstElement, GST_TYPE_ELEMENT, _do_init);
| type: | the name of the type struct | 
| type_as_function: | the prefix for the functions | 
| parent_type: | the parent type struct name | 
| parent_type_macro: | the parent type macro | 
| additional_initializations: | function pointer in the form of void additional_initializations (GType type) that can be used for initializing interfaces and the like | 
#define GST_BOILERPLATE(type,type_as_function,parent_type,parent_type_macro)
Define the boilerplate type stuff to reduce typos and code size. Defines the get_type method and the parent_class static variable.
GST_BOILERPLATE (GstFdSink, gst_fdsink, GstElement, GST_TYPE_ELEMENT);
| type: | the name of the type struct | 
| type_as_function: | the prefix for the functions | 
| parent_type: | the parent type struct name | 
| parent_type_macro: | the parent type macro | 
#define GST_CALL_PARENT(parent_class_cast, name, args)
Just call the parent handler. This assumes that there is a variable named parent_class that points to the (duh!) parent class. Note that this macro is not to be used with things that return something, use the _WITH_DEFAULT version for that
| parent_class_cast: | the name of the class cast macro for the parent type | 
| name: | name of the function to call | 
| args: | arguments enclosed in '( )' | 
#define GST_CALL_PARENT_WITH_DEFAULT(parent_class_cast, name, args, def_return)
Same as GST_CALL_PARENT(), but in case there is no implementation, it
evaluates to def_return.
| parent_class_cast: | the name of the class cast macro for the parent type | 
| name: | name of the function to call | 
| args: | arguments enclosed in '( )' | 
| def_return: | default result | 
#define GST_READ_UINT8(data)
Read an 8 bit unsigned integer value from the memory buffer.
| data: | memory location | 
#define GST_READ_UINT16_LE(data)
Read a 16 bit unsigned integer value in little endian format from the memory buffer.
| data: | memory location | 
#define GST_READ_UINT16_BE(data)
Read a 16 bit unsigned integer value in big endian format from the memory buffer.
| data: | memory location | 
#define GST_READ_UINT32_LE(data)
Read a 32 bit unsigned integer value in little endian format from the memory buffer.
| data: | memory location | 
#define GST_READ_UINT32_BE(data)
Read a 32 bit unsigned integer value in big endian format from the memory buffer.
| data: | memory location | 
#define GST_READ_UINT64_LE(data)
Read a 64 bit unsigned integer value in little endian format from the memory buffer.
| data: | memory location | 
#define GST_READ_UINT64_BE(data)
Read a 64 bit unsigned integer value in big endian format from the memory buffer.
| data: | memory location | 
#define GST_WRITE_UINT8(data, num)
Store an 8 bit unsigned integer value into the memory buffer.
| data: | memory location | 
| num: | value to store | 
#define GST_WRITE_UINT16_LE(data, num)
Store a 16 bit unsigned integer value in little endian format into the memory buffer.
| data: | memory location | 
| num: | value to store | 
#define GST_WRITE_UINT16_BE(data, num)
Store a 16 bit unsigned integer value in big endian format into the memory buffer.
| data: | memory location | 
| num: | value to store | 
#define GST_WRITE_UINT32_LE(data, num)
Store a 32 bit unsigned integer value in little endian format into the memory buffer.
| data: | memory location | 
| num: | value to store | 
#define GST_WRITE_UINT32_BE(data, num)
Store a 32 bit unsigned integer value in big endian format into the memory buffer.
| data: | memory location | 
| num: | value to store | 
#define GST_WRITE_UINT64_LE(data, num)
Store a 64 bit unsigned integer value in little endian format into the memory buffer.
| data: | memory location | 
| num: | value to store | 
#define GST_WRITE_UINT64_BE(data, num)
Store a 64 bit unsigned integer value in big endian format into the memory buffer.
| data: | memory location | 
| num: | value to store | 
#define GST_ROUND_UP_2(num) (((num)+1)&~1)
Make number divideable by two without a rest.
| num: | value round up | 
#define GST_ROUND_UP_4(num) (((num)+3)&~3)
Make number divideable by four without a rest.
| num: | value round up | 
#define GST_ROUND_UP_8(num) (((num)+7)&~7)
Make number divideable by eight without a rest.
| num: | value round up | 
#define GST_ROUND_UP_16(num) (((num)+15)&~15)
Make number divideable by 16 without a rest.
| num: | value round up | 
#define GST_ROUND_UP_32(num) (((num)+31)&~31)
Make number divideable by 32 without a rest.
| num: | value round up | 
#define GST_ROUND_UP_64(num) (((num)+63)&~63)
Make number divideable by 64 without a rest.
| num: | value round up | 
void gst_atomic_int_set (gint *atomic_int, gint value);
Unconditionally sets the atomic integer to value.
| atomic_int: | pointer to an atomic integer | 
| value: | value to set | 
const gchar* gst_flow_get_name (GstFlowReturn ret);
Gets a string representing the given flow return.
| ret: | a GstFlowReturn to get the name of. | 
| Returns : | a string with the name of the flow return. | 
GQuark gst_flow_to_quark (GstFlowReturn ret);
Get the unique quark for the given GstFlowReturn.
| ret: | a GstFlowReturn to get the quark of. | 
| Returns : | the quark associated with the flow return or 0 if an invalid return was specified. | 
void gst_print_element_args (GString *buf, gint indent, GstElement *element);
Print the element argument in a human readable format in the given GString.
| buf: | the buffer to print the args in | 
| indent: | initial indentation | 
| element: | the element to print the args of | 
void gst_print_pad_caps (GString *buf, gint indent, GstPad *pad);
Write the pad capabilities in a human readable format into the given GString.
| buf: | the buffer to print the caps in | 
| indent: | initial indentation | 
| pad: | the pad to print the caps from | 
#define gst_guint64_to_gdouble(value)
Convert value to a gdouble.
| value: | the guint64 value to convert | 
#define gst_gdouble_to_guint64(value)
Convert value to a guint64.
| value: | the gdouble value to convert | 
void gst_util_dump_mem (const guchar *mem, guint size);
Dumps the memory block into a hex representation. Useful for debugging.
| mem: | a pointer to the memory to dump | 
| size: | the size of the memory block to dump | 
guint64 gst_util_uint64_scale (guint64 val, guint64 num, guint64 denom);
Scale val by num / denom, trying to avoid overflows.
This function can potentially be very slow if denom > G_MAXUINT32.
| val: | the number to scale | 
| num: | the numerator of the scale ratio | 
| denom: | the denominator of the scale ratio | 
| Returns : | val*num/denom, trying to avoid overflows. | 
guint64 gst_util_uint64_scale_int (guint64 val, gint num, gint denom);
Scale a guint64 by a factor expressed as a fraction (num/denom), avoiding overflows and loss of precision.
num and denom must be positive integers. denom cannot be 0.
| val: | guint64 (such as a GstClockTime) to scale. | 
| num: | numerator of the scale factor. | 
| denom: | denominator of the scale factor. | 
| Returns : | val*num/denom, avoiding overflow and loss of precision | 
void gst_util_set_object_arg (GObject *object, const gchar *name, const gchar *value);
Convertes the string value to the type of the objects argument and sets the argument with it.
| object: | the object to set the argument of | 
| name: | the name of the argument to set | 
| value: | the string value to set | 
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