diff -r 000000000000 -r 0e761a78d257 gstreamer_core/gst/gstbuffer.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gstreamer_core/gst/gstbuffer.h Thu Dec 17 08:53:32 2009 +0200 @@ -0,0 +1,508 @@ +/* GStreamer + * Copyright (C) 1999,2000 Erik Walthinsen + * 2000 Wim Taymans + * + * gstbuffer.h: Header for GstBuffer object + * + * 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_BUFFER_H__ +#define __GST_BUFFER_H__ + +#include +#include +#include + +G_BEGIN_DECLS + +typedef struct _GstBuffer GstBuffer; +typedef struct _GstBufferClass GstBufferClass; + +/** + * GST_BUFFER_TRACE_NAME: + * + * The name used for tracing memory allocations. + */ +#define GST_BUFFER_TRACE_NAME "GstBuffer" + +#define GST_TYPE_BUFFER (gst_buffer_get_type()) +#define GST_IS_BUFFER(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_BUFFER)) +#define GST_IS_BUFFER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_BUFFER)) +#define GST_BUFFER_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_BUFFER, GstBufferClass)) +#define GST_BUFFER(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_BUFFER, GstBuffer)) +#define GST_BUFFER_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_BUFFER, GstBufferClass)) +#define GST_BUFFER_CAST(obj) ((GstBuffer *)(obj)) + +/** + * GST_BUFFER_FLAGS: + * @buf: a #GstBuffer. + * + * A flags word containing #GstBufferFlag flags set on this buffer. + */ +#define GST_BUFFER_FLAGS(buf) GST_MINI_OBJECT_FLAGS(buf) +/** + * GST_BUFFER_FLAG_IS_SET: + * @buf: a #GstBuffer. + * @flag: the #GstBufferFlag to check. + * + * Gives the status of a specific flag on a buffer. + */ +#define GST_BUFFER_FLAG_IS_SET(buf,flag) GST_MINI_OBJECT_FLAG_IS_SET (buf, flag) +/** + * GST_BUFFER_FLAG_SET: + * @buf: a #GstBuffer. + * @flag: the #GstBufferFlag to set. + * + * Sets a buffer flag on a buffer. + */ +#define GST_BUFFER_FLAG_SET(buf,flag) GST_MINI_OBJECT_FLAG_SET (buf, flag) +/** + * GST_BUFFER_FLAG_UNSET: + * @buf: a #GstBuffer. + * @flag: the #GstBufferFlag to clear. + * + * Clears a buffer flag. + */ +#define GST_BUFFER_FLAG_UNSET(buf,flag) GST_MINI_OBJECT_FLAG_UNSET (buf, flag) + +/** + * GST_BUFFER_DATA: + * @buf: a #GstBuffer. + * + * A pointer to the data element of this buffer. + */ +#define GST_BUFFER_DATA(buf) (GST_BUFFER_CAST(buf)->data) +/** + * GST_BUFFER_SIZE: + * @buf: a #GstBuffer. + * + * The size in bytes of the data in this buffer. + */ +#define GST_BUFFER_SIZE(buf) (GST_BUFFER_CAST(buf)->size) +/** + * GST_BUFFER_TIMESTAMP: + * @buf: a #GstBuffer.: + * + * The timestamp in nanoseconds (as a #GstClockTime) of the data in the buffer. + * Value will be %GST_CLOCK_TIME_NONE if the timestamp is unknown. + * + */ +#define GST_BUFFER_TIMESTAMP(buf) (GST_BUFFER_CAST(buf)->timestamp) +/** + * GST_BUFFER_DURATION: + * @buf: a #GstBuffer. + * + * The duration in nanoseconds (as a #GstClockTime) of the data in the buffer. + * Value will be %GST_CLOCK_TIME_NONE if the duration is unknown. + */ +#define GST_BUFFER_DURATION(buf) (GST_BUFFER_CAST(buf)->duration) +/** + * GST_BUFFER_CAPS: + * @buf: a #GstBuffer. + * + * The caps for this buffer. + */ +#define GST_BUFFER_CAPS(buf) (GST_BUFFER_CAST(buf)->caps) +/** + * GST_BUFFER_OFFSET: + * @buf: a #GstBuffer. + * + * The offset in the source file of the beginning of this buffer. + */ +#define GST_BUFFER_OFFSET(buf) (GST_BUFFER_CAST(buf)->offset) +/** + * GST_BUFFER_OFFSET_END: + * @buf: a #GstBuffer. + * + * The offset in the source file of the end of this buffer. + */ +#define GST_BUFFER_OFFSET_END(buf) (GST_BUFFER_CAST(buf)->offset_end) +/** + * GST_BUFFER_MALLOCDATA: + * @buf: a #GstBuffer. + * + * A pointer to any data allocated for this buffer using g_malloc(). If this is + * non-NULL, this memory will be freed at the end of the buffer's lifecycle + * (i.e. when its refcount becomes zero). + */ +#define GST_BUFFER_MALLOCDATA(buf) (GST_BUFFER_CAST(buf)->malloc_data) + +/** + * GST_BUFFER_OFFSET_NONE: + * + * Constant for no-offset return results. + */ +#define GST_BUFFER_OFFSET_NONE ((guint64)-1) + +/** + * GST_BUFFER_DURATION_IS_VALID: + * @buffer: a #GstBuffer + * + * Tests if the duration is known. + */ +#define GST_BUFFER_DURATION_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_DURATION (buffer))) +/** + * GST_BUFFER_TIMESTAMP_IS_VALID: + * @buffer: a #GstBuffer + * + * Tests if the timestamp is known. + */ +#define GST_BUFFER_TIMESTAMP_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_TIMESTAMP (buffer))) +/** + * GST_BUFFER_OFFSET_IS_VALID: + * @buffer: a #GstBuffer + * + * Tests if the start offset is known. + */ +#define GST_BUFFER_OFFSET_IS_VALID(buffer) (GST_BUFFER_OFFSET (buffer) != GST_BUFFER_OFFSET_NONE) +/** + * GST_BUFFER_OFFSET_END_IS_VALID: + * @buffer: a #GstBuffer + * + * Tests if the end offset is known. + */ +#define GST_BUFFER_OFFSET_END_IS_VALID(buffer) (GST_BUFFER_OFFSET_END (buffer) != GST_BUFFER_OFFSET_NONE) +/** + * GST_BUFFER_IS_DISCONT: + * @buffer: a #GstBuffer + * + * Tests if the buffer marks a discontinuity in the stream. + * + * Since: 0.10.9 + */ +#define GST_BUFFER_IS_DISCONT(buffer) (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DISCONT)) + +/** + * GstBufferFlag: + * @GST_BUFFER_FLAG_READONLY: the buffer is read-only. This means the data of + * the buffer should not be modified. The metadata might still be modified. + * @GST_BUFFER_FLAG_PREROLL: the buffer is part of a preroll and should not be + * displayed. + * @GST_BUFFER_FLAG_DISCONT: the buffer marks a discontinuity in the stream. + * This typically occurs after a seek or a dropped buffer from a live or + * network source. + * @GST_BUFFER_FLAG_IN_CAPS: the buffer has been added as a field in a #GstCaps. + * @GST_BUFFER_FLAG_GAP: the buffer has been created to fill a gap in the + * stream and contains media neutral data (elements can switch to optimized code + * path that ignores the buffer content). + * @GST_BUFFER_FLAG_DELTA_UNIT: this unit cannot be decoded independently. + * @GST_BUFFER_FLAG_LAST: additional flags can be added starting from this flag. + * + * A set of buffer flags used to describe properties of a #GstBuffer. + */ +typedef enum { + GST_BUFFER_FLAG_READONLY = GST_MINI_OBJECT_FLAG_READONLY, + GST_BUFFER_FLAG_PREROLL = (GST_MINI_OBJECT_FLAG_LAST << 0), + GST_BUFFER_FLAG_DISCONT = (GST_MINI_OBJECT_FLAG_LAST << 1), + GST_BUFFER_FLAG_IN_CAPS = (GST_MINI_OBJECT_FLAG_LAST << 2), + GST_BUFFER_FLAG_GAP = (GST_MINI_OBJECT_FLAG_LAST << 3), + GST_BUFFER_FLAG_DELTA_UNIT = (GST_MINI_OBJECT_FLAG_LAST << 4), + /* padding */ + GST_BUFFER_FLAG_LAST = (GST_MINI_OBJECT_FLAG_LAST << 8) +} GstBufferFlag; + +/** + * GstBuffer: + * @mini_object: the parent structure + * @data: pointer to the buffer data + * @size: size of buffer data + * @timestamp: timestamp of the buffer, can be #GST_CLOCK_TIME_NONE when the + * timestamp is not known or relevant. + * @duration: duration in time of the buffer data, can be #GST_CLOCK_TIME_NONE + * when the duration is not known or relevant. + * @caps: the #GstCaps describing the data format in this buffer + * @offset: a media specific offset for the buffer data. + * For video frames, this is the frame number of this buffer. + * For audio samples, this is the offset of the first sample in this buffer. + * For file data or compressed data this is the byte offset of the first + * byte in this buffer. + * @offset_end: the last offset contained in this buffer. It has the same + * format as @offset. + * @malloc_data: a pointer to the allocated memory associated with this buffer. + * When the buffer is freed, this data will freed with g_free(). + * + * The structure of a #GstBuffer. Use the associated macros to access the public + * variables. + */ +struct _GstBuffer { + GstMiniObject mini_object; + + /*< public >*/ /* with COW */ + /* pointer to data and its size */ + guint8 *data; + guint size; + + /* timestamp */ + GstClockTime timestamp; + GstClockTime duration; + + /* the media type of this buffer */ + GstCaps *caps; + + /* media specific offset */ + guint64 offset; + guint64 offset_end; + + guint8 *malloc_data; + + /*< private >*/ + gpointer _gst_reserved[GST_PADDING]; +}; + +struct _GstBufferClass { + GstMiniObjectClass mini_object_class; +}; +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + + +GType gst_buffer_get_type (void); + +/* allocation */ +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +GstBuffer * gst_buffer_new (void); +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +GstBuffer * gst_buffer_new_and_alloc (guint size); +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +GstBuffer * gst_buffer_try_new_and_alloc (guint size); + +/** + * gst_buffer_set_data: + * @buf: a #GstBuffer + * @data: The data (a #guint8 *) to set on the buffer. + * @size: The size (in bytes, as a #guint) of the data being set. + * + * A convenience function to set the data and size on a buffer. + * This will replace any existing data pointer set on this buffer, but will + * not change GST_BUFFER_MALLOCDATA(), if any. Callers should ensure that + * GST_BUFFER_MALLOCDATA() is non-NULL, or should free that and set it to NULL. + * + * No checks are done on the data or size arguments passed. + */ +#define gst_buffer_set_data(buf, data, size) \ +G_STMT_START { \ + GST_BUFFER_DATA (buf) = data; \ + GST_BUFFER_SIZE (buf) = size; \ +} G_STMT_END + +/* refcounting */ +/** + * gst_buffer_ref: + * @buf: a #GstBuffer. + * + * Increases the refcount of the given buffer by one. + * + * Note that the refcount affects the writeability + * of @buf and its metadata, see gst_buffer_is_writable() and + * gst_buffer_is_metadata_writable(). It is + * important to note that keeping additional references to + * GstBuffer instances can potentially increase the number + * of memcpy operations in a pipeline. + * + * Returns: @buf + */ +#ifdef _FOOL_GTK_DOC_ +G_INLINE_FUNC GstBuffer * gst_buffer_ref (GstBuffer * buf); +#endif + +static inline GstBuffer * +gst_buffer_ref (GstBuffer * buf) +{ + /* not using a macro here because gcc-4.1 will complain + * if the return value isn't used (because of the cast) */ + return (GstBuffer *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (buf)); +} + +/** + * gst_buffer_unref: + * @buf: a #GstBuffer. + * + * Decreases the refcount of the buffer. If the refcount reaches 0, the buffer + * will be freed. If GST_BUFFER_MALLOCDATA() is non-NULL, this pointer will + * also be freed at this time. + */ +#define gst_buffer_unref(buf) gst_mini_object_unref (GST_MINI_OBJECT_CAST (buf)) + +/* copy buffer */ +/** + * gst_buffer_copy: + * @buf: a #GstBuffer. + * + * Create a copy of the given buffer. This will also make a newly allocated + * copy of the data the source buffer contains. + */ +#define gst_buffer_copy(buf) GST_BUFFER_CAST (gst_mini_object_copy (GST_MINI_OBJECT_CAST (buf))) + +/** + * GstBufferCopyFlags: + * @GST_BUFFER_COPY_FLAGS: flag indicating that buffer flags should be copied + * @GST_BUFFER_COPY_TIMESTAMPS: flag indicating that buffer timestamp, duration, + * offset and offset_end should be copied + * @GST_BUFFER_COPY_CAPS: flag indicating that buffer caps should be copied + * + * A set of flags that can be provided to the gst_buffer_copy_metadata() + * function to specify which metadata fields should be copied. + * + * Since: 0.10.13 + */ +typedef enum { + GST_BUFFER_COPY_FLAGS = (1 << 0), + GST_BUFFER_COPY_TIMESTAMPS = (1 << 1), + GST_BUFFER_COPY_CAPS = (1 << 2) +} GstBufferCopyFlags; + +/** + * GST_BUFFER_COPY_ALL: + * + * Combination of all possible fields that can be copied with + * gst_buffer_copy_metadata(). + * + * Since: 0.10.13 + */ +#define GST_BUFFER_COPY_ALL (GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_CAPS) + +/* copies metadata into newly allocated buffer */ +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +void gst_buffer_copy_metadata (GstBuffer *dest, const GstBuffer *src, + GstBufferCopyFlags flags); + +/** + * gst_buffer_is_writable: + * @buf: a #GstBuffer + * + * Tests if you can safely write data into a buffer's data array or validly + * modify the caps and timestamp metadata. Metadata in a GstBuffer is always + * writable, but it is only safe to change it when there is only one owner + * of the buffer - ie, the refcount is 1. + */ +#define gst_buffer_is_writable(buf) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (buf)) +/** + * gst_buffer_make_writable: + * @buf: a #GstBuffer + * + * Makes a writable buffer from the given buffer. If the source buffer is + * already writable, this will simply return the same buffer. A copy will + * otherwise be made using gst_buffer_copy(). + */ +#define gst_buffer_make_writable(buf) GST_BUFFER_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (buf))) + +/* Ensure that the metadata of the buffer is writable, even if the buffer data + * isn't */ +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +gboolean gst_buffer_is_metadata_writable (GstBuffer *buf); +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +GstBuffer* gst_buffer_make_metadata_writable (GstBuffer *buf); + +/** + * gst_buffer_replace: + * @obuf: pointer to a pointer to a #GstBuffer to be replaced. + * @nbuf: pointer to a #GstBuffer that will replace the buffer pointed to by + * @obuf. + * + * Modifies a pointer to a #Gstbuffer to point to a different #GstBuffer. The + * modification is done atomically (so this is useful for ensuring thread safety + * in some cases), and the reference counts are updated appropriately (the old + * buffer is unreffed, the new is reffed). + * + * Either @nbuf or the #GstBuffer pointed to by @obuf may be NULL. + */ +#define gst_buffer_replace(obuf,nbuf) \ +G_STMT_START { \ + GstBuffer **___obufaddr = (GstBuffer **)(obuf); \ + gst_mini_object_replace ((GstMiniObject **)___obufaddr, \ + GST_MINI_OBJECT_CAST (nbuf)); \ +} G_STMT_END +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + + +GstCaps* gst_buffer_get_caps (GstBuffer *buffer); +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +void gst_buffer_set_caps (GstBuffer *buffer, GstCaps *caps); + +/* creating a subbuffer */ +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +GstBuffer* gst_buffer_create_sub (GstBuffer *parent, guint offset, guint size); + +/* span, two buffers, intelligently */ +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +gboolean gst_buffer_is_span_fast (GstBuffer *buf1, GstBuffer *buf2); +#ifdef __SYMBIAN32__ +IMPORT_C +#endif + +GstBuffer* gst_buffer_span (GstBuffer *buf1, guint32 offset, GstBuffer *buf2, guint32 len); + +/** + * gst_value_set_buffer: + * @v: a #GstValue to receive the data + * @b: a #GstBuffer to assign to the GstValue + * + * Sets @b as the value of @v. Caller retains reference to buffer. + */ +#define gst_value_set_buffer(v,b) gst_value_set_mini_object(v, GST_MINI_OBJECT_CAST(b)) +/** + * gst_value_take_buffer: + * @v: a #GstValue to receive the data + * @b: a #GstBuffer to assign to the GstValue + * + * Sets @b as the value of @v. Caller gives away reference to buffer. + */ +#define gst_value_take_buffer(v,b) gst_value_take_mini_object(v, GST_MINI_OBJECT_CAST(b)) +/** + * gst_value_get_buffer: + * @v: a #GstValue to qeury + * + * Receives a #GstBuffer as the value of @v. Does not return a reference to + * the buffer, so the pointer is only valid for as long as the caller owns + * a reference to @v. + */ +#define gst_value_get_buffer(v) GST_BUFFER_CAST (gst_value_get_mini_object(v)) + +G_END_DECLS + +#endif /* __GST_BUFFER_H__ */