gstreamer/gst/gstvalue.h

542 lines
16 KiB
C

/* GStreamer
* Copyright (C) <2003> David A. Schleef <ds@schleef.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_VALUE_H__
#define __GST_VALUE_H__
#include <gst/gstconfig.h>
#include <gst/gstcaps.h>
#include <gst/gststructure.h>
G_BEGIN_DECLS
/**
* GST_MAKE_FOURCC:
* @a: the first character
* @b: the second character
* @c: the third character
* @d: the fourth character
*
* Transform four characters into a #guint32 fourcc value with host
* endianness.
* <informalexample>
* <programlisting>
* guint32 fourcc = GST_MAKE_FOURCC ('M', 'J', 'P', 'G');
* </programlisting>
* </informalexample>
*/
#define GST_MAKE_FOURCC(a,b,c,d) ((guint32)((a)|(b)<<8|(c)<<16|(d)<<24))
/**
* GST_STR_FOURCC:
* @f: a string with at least four characters
*
* Transform an input string into a #guint32 fourcc value with host
* endianness.
* Caller is responsible for ensuring the input string consists of at least
* four characters.
* <informalexample>
* <programlisting>
* guint32 fourcc = GST_STR_FOURCC ("MJPG");
* </programlisting>
* </informalexample>
*/
#define GST_STR_FOURCC(f) ((guint32)(((f)[0])|((f)[1]<<8)|((f)[2]<<16)|((f)[3]<<24)))
/**
* GST_FOURCC_FORMAT:
*
* Can be used together with #GST_FOURCC_ARGS to properly output a
* #guint32 fourcc value in a printf()-style text message.
* <informalexample>
* <programlisting>
* printf ("fourcc: %" GST_FOURCC_FORMAT "\n", GST_FOURCC_ARGS (fcc));
* </programlisting>
* </informalexample>
*/
#define GST_FOURCC_FORMAT "c%c%c%c"
/**
* GST_FOURCC_ARGS:
* @fourcc: a #guint32 fourcc value to output
*
* Can be used together with #GST_FOURCC_FORMAT to properly output a
* #guint32 fourcc value in a printf()-style text message.
*/
#define GST_FOURCC_ARGS(fourcc) \
((gchar) ((fourcc) &0xff)), \
((gchar) (((fourcc)>>8 )&0xff)), \
((gchar) (((fourcc)>>16)&0xff)), \
((gchar) (((fourcc)>>24)&0xff))
/**
* GST_VALUE_HOLDS_FOURCC:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_FOURCC value.
*/
#define GST_VALUE_HOLDS_FOURCC(x) (G_VALUE_HOLDS((x), gst_fourcc_get_type ()))
/**
* GST_VALUE_HOLDS_INT_RANGE:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_INT_RANGE value.
*/
#define GST_VALUE_HOLDS_INT_RANGE(x) (G_VALUE_HOLDS((x), gst_int_range_get_type ()))
/**
* GST_VALUE_HOLDS_DOUBLE_RANGE:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_DOUBLE_RANGE value.
*/
#define GST_VALUE_HOLDS_DOUBLE_RANGE(x) (G_VALUE_HOLDS((x), gst_double_range_get_type ()))
/**
* GST_VALUE_HOLDS_FRACTION_RANGE:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_FRACTION_RANGE value.
*/
#define GST_VALUE_HOLDS_FRACTION_RANGE(x) (G_VALUE_HOLDS((x), gst_fraction_range_get_type ()))
/**
* GST_VALUE_HOLDS_LIST:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_LIST value.
*/
#define GST_VALUE_HOLDS_LIST(x) (G_VALUE_HOLDS((x), gst_value_list_get_type ()))
/**
* GST_VALUE_HOLDS_ARRAY:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_ARRAY value.
*/
#define GST_VALUE_HOLDS_ARRAY(x) (G_VALUE_HOLDS((x), gst_value_array_get_type ()))
/**
* GST_VALUE_HOLDS_CAPS:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_CAPS value.
*/
#define GST_VALUE_HOLDS_CAPS(x) (G_VALUE_HOLDS((x), GST_TYPE_CAPS))
/**
* GST_VALUE_HOLDS_STRUCTURE:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_STRUCTURE value.
*
* Since: 0.10.15
*/
#define GST_VALUE_HOLDS_STRUCTURE(x) (G_VALUE_HOLDS((x), GST_TYPE_STRUCTURE))
/**
* GST_VALUE_HOLDS_BUFFER:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_BUFFER value.
*/
#define GST_VALUE_HOLDS_BUFFER(x) (G_VALUE_HOLDS((x), GST_TYPE_BUFFER))
/**
* GST_VALUE_HOLDS_FRACTION:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_FRACTION value.
*/
#define GST_VALUE_HOLDS_FRACTION(x) (G_VALUE_HOLDS((x), gst_fraction_get_type ()))
/**
* GST_VALUE_HOLDS_DATE:
* @x: the #GValue to check
*
* Checks if the given #GValue contains a #GST_TYPE_DATE value.
*/
#define GST_VALUE_HOLDS_DATE(x) (G_VALUE_HOLDS((x), gst_date_get_type ()))
/**
* GST_TYPE_FOURCC:
*
* a #GValue type that represents 4 byte identifier (e.g. used for codecs)
*
* Returns: the #GType of GstFourcc
*/
#define GST_TYPE_FOURCC gst_fourcc_get_type ()
/**
* GST_TYPE_INT_RANGE:
*
* a #GValue type that represents an integer range
*
* Returns: the #GType of GstIntRange
*/
#define GST_TYPE_INT_RANGE gst_int_range_get_type ()
/**
* GST_TYPE_DOUBLE_RANGE:
*
* a #GValue type that represents a floating point range with double precission
*
* Returns: the #GType of GstIntRange
*/
#define GST_TYPE_DOUBLE_RANGE gst_double_range_get_type ()
/**
* GST_TYPE_FRACTION_RANGE:
*
* a #GValue type that represents a GstFraction range
*
* Returns: the #GType of GstFractionRange
*/
#define GST_TYPE_FRACTION_RANGE gst_fraction_range_get_type ()
/**
* GST_TYPE_LIST:
*
* a #GValue type that represents an unordered list of #GValue values. This
* is used for example to express a list of possible values for a field in
* a caps structure, like a list of possible sample rates, of which only one
* will be chosen in the end. This means that all values in the list are
* meaningful on their own.
*
* Returns: the #GType of GstValueList (which is not explicitly typed)
*/
#define GST_TYPE_LIST gst_value_list_get_type ()
/**
* GST_TYPE_ARRAY:
*
* a #GValue type that represents an ordered list of #GValue values. This is
* used to express a set of values that is meaningful only in their specific
* combination and order of values. Each value on its own is not particularly
* meaningful, only the ordered array in its entirety is meaningful. This is
* used for example to express channel layouts for multichannel audio where
* each channel needs to be mapped to a position in the room.
*
* Returns: the #GType of GstArrayList (which is not explicitly typed)
*/
#define GST_TYPE_ARRAY gst_value_array_get_type ()
/**
* GST_TYPE_FRACTION:
*
* a #GValue type that represents a fraction of an integer numerator over
* an integer denominator
*
* Returns: the #GType of GstFraction (which is not explicitly typed)
*/
#define GST_TYPE_FRACTION gst_fraction_get_type ()
/**
* GST_TYPE_DATE:
*
* a boxed #GValue type for #GDate that represents a date.
*
* Returns: the #GType of GstDate
*/
#define GST_TYPE_DATE gst_date_get_type ()
/**
* GST_VALUE_LESS_THAN:
*
* Indicates that the first value provided to a comparison function
* (gst_value_compare()) is lesser than the second one.
*/
#define GST_VALUE_LESS_THAN (-1)
/**
* GST_VALUE_EQUAL:
*
* Indicates that the first value provided to a comparison function
* (gst_value_compare()) is equal to the second one.
*/
#define GST_VALUE_EQUAL 0
/**
* GST_VALUE_GREATER_THAN:
*
* Indicates that the first value provided to a comparison function
* (gst_value_compare()) is greater than the second one.
*/
#define GST_VALUE_GREATER_THAN 1
/**
* GST_VALUE_UNORDERED:
*
* Indicates that the comparison function (gst_value_compare()) can not
* determine a order for the two provided values.
*/
#define GST_VALUE_UNORDERED 2
/**
* GstValueCompareFunc:
* @value1: first value for comparission
* @value2: second value for comparission
*
* Used together with gst_value_compare() to compare #GValues.
*
* Returns: one of GST_VALUE_LESS_THAN, GST_VALUE_EQUAL, GST_VALUE_GREATER_THAN
* or GST_VALUE_UNORDERED
*/
typedef gint (* GstValueCompareFunc) (const GValue *value1,
const GValue *value2);
/**
* GstValueSerializeFunc:
* @value1: a #GValue
*
* Used by gst_value_serialize() to obtain a non-binary form of the #GValue.
*
* Returns: the string representation of the value
*/
typedef gchar * (* GstValueSerializeFunc) (const GValue *value1);
/**
* GstValueDeserializeFunc:
* @dest: a #GValue
* @s: a string
*
* Used by gst_value_deserialize() to parse a non-binary form into the #GValue.
*
* Returns: %TRUE for success
*/
typedef gboolean (* GstValueDeserializeFunc) (GValue *dest,
const gchar *s);
/**
* GstValueUnionFunc:
* @dest: a #GValue for the result
* @value1: a #GValue operand
* @value2: a #GValue operand
*
* Used by gst_value_union() to perform unification for a specific #GValue
* type. Register a new implementation with gst_value_register_union_func().
*
* Returns: %TRUE if a union was successful
*/
typedef gboolean (* GstValueUnionFunc) (GValue *dest,
const GValue *value1,
const GValue *value2);
/**
* GstValueIntersectFunc:
* @dest: a #GValue for the result
* @value1: a #GValue operand
* @value2: a #GValue operand
*
* Used by gst_value_intersect() to perform intersection for a specific #GValue
* type. If the intersection is non-empty, the result is
* placed in @dest and TRUE is returned. If the intersection is
* empty, @dest is unmodified and FALSE is returned.
* Register a new implementation with gst_value_register_intersection_func().
*
* Returns: %TRUE if the values can intersect
*/
typedef gboolean (* GstValueIntersectFunc) (GValue *dest,
const GValue *value1,
const GValue *value2);
/**
* GstValueSubtractFunc:
* @dest: a #GValue for the result
* @minuend: a #GValue operand
* @subtrahend: a #GValue operand
*
* Used by gst_value_subtract() to perform subtraction for a specific #GValue
* type. Register a new implementation with gst_value_register_subtract_func().
*
* Returns: %TRUE if the subtraction is not empty
*/
typedef gboolean (* GstValueSubtractFunc) (GValue *dest,
const GValue *minuend,
const GValue *subtrahend);
typedef struct _GstValueTable GstValueTable;
/**
* GstValueTable:
* @type: a #GType
* @compare: a #GstValueCompareFunc
* @serialize: a #GstValueSerializeFunc
* @deserialize: a #GstValueDeserializeFunc
*
* VTable for the #GValue @type.
*/
struct _GstValueTable {
GType type;
GstValueCompareFunc compare;
GstValueSerializeFunc serialize;
GstValueDeserializeFunc deserialize;
/*< private >*/
void *_gst_reserved [GST_PADDING];
};
GType gst_int_range_get_type (void);
GType gst_double_range_get_type (void);
GType gst_fraction_range_get_type (void);
GType gst_fourcc_get_type (void);
GType gst_fraction_get_type (void);
GType gst_value_list_get_type (void);
GType gst_value_array_get_type (void);
GType gst_date_get_type (void);
void gst_value_register (const GstValueTable *table);
void gst_value_init_and_copy (GValue *dest,
const GValue *src);
gchar * gst_value_serialize (const GValue *value);
gboolean gst_value_deserialize (GValue *dest,
const gchar *src);
/* list */
void gst_value_list_append_value (GValue *value,
const GValue *append_value);
void gst_value_list_prepend_value (GValue *value,
const GValue *prepend_value);
void gst_value_list_concat (GValue *dest,
const GValue *value1,
const GValue *value2);
guint gst_value_list_get_size (const GValue *value);
G_CONST_RETURN GValue *
gst_value_list_get_value (const GValue *value,
guint index);
/* array */
void gst_value_array_append_value (GValue *value,
const GValue *append_value);
void gst_value_array_prepend_value (GValue *value,
const GValue *prepend_value);
guint gst_value_array_get_size (const GValue *value);
G_CONST_RETURN GValue *
gst_value_array_get_value (const GValue *value,
guint index);
/* fourcc */
void gst_value_set_fourcc (GValue *value,
guint32 fourcc);
guint32 gst_value_get_fourcc (const GValue *value);
/* int range */
void gst_value_set_int_range (GValue *value,
gint start,
gint end);
gint gst_value_get_int_range_min (const GValue *value);
gint gst_value_get_int_range_max (const GValue *value);
/* double range */
void gst_value_set_double_range (GValue *value,
gdouble start,
gdouble end);
gdouble gst_value_get_double_range_min (const GValue *value);
gdouble gst_value_get_double_range_max (const GValue *value);
/* caps */
G_CONST_RETURN GstCaps *
gst_value_get_caps (const GValue *value);
void gst_value_set_caps (GValue *value,
const GstCaps *caps);
/* structure */
G_CONST_RETURN GstStructure *
gst_value_get_structure (const GValue *value);
void gst_value_set_structure (GValue *value,
const GstStructure *structure);
/* fraction */
void gst_value_set_fraction (GValue *value,
gint numerator,
gint denominator);
gint gst_value_get_fraction_numerator (const GValue *value);
gint gst_value_get_fraction_denominator(const GValue *value);
gboolean gst_value_fraction_multiply (GValue *product,
const GValue *factor1,
const GValue *factor2);
gboolean gst_value_fraction_subtract (GValue * dest,
const GValue * minuend,
const GValue * subtrahend);
/* fraction range */
void gst_value_set_fraction_range (GValue *value,
const GValue *start,
const GValue *end);
void gst_value_set_fraction_range_full (GValue *value,
gint numerator_start,
gint denominator_start,
gint numerator_end,
gint denominator_end);
const GValue *gst_value_get_fraction_range_min (const GValue *value);
const GValue *gst_value_get_fraction_range_max (const GValue *value);
/* date */
G_CONST_RETURN GDate *
gst_value_get_date (const GValue *value);
void gst_value_set_date (GValue *value,
const GDate *date);
/* compare */
gint gst_value_compare (const GValue *value1,
const GValue *value2);
gboolean gst_value_can_compare (const GValue *value1,
const GValue *value2);
/* union */
gboolean gst_value_union (GValue *dest,
const GValue *value1,
const GValue *value2);
gboolean gst_value_can_union (const GValue *value1,
const GValue *value2);
void gst_value_register_union_func (GType type1,
GType type2,
GstValueUnionFunc func);
/* intersection */
gboolean gst_value_intersect (GValue *dest,
const GValue *value1,
const GValue *value2);
gboolean gst_value_can_intersect (const GValue *value1,
const GValue *value2);
void gst_value_register_intersect_func (GType type1,
GType type2,
GstValueIntersectFunc func);
/* subtraction */
gboolean gst_value_subtract (GValue *dest,
const GValue *minuend,
const GValue *subtrahend);
gboolean gst_value_can_subtract (const GValue *minuend,
const GValue *subtrahend);
void gst_value_register_subtract_func (GType minuend_type,
GType subtrahend_type,
GstValueSubtractFunc func);
/* fixation */
gboolean gst_value_is_fixed (const GValue *value);
G_END_DECLS
#endif