gstreamer/gst/gstmeta.c
Wim Taymans 9339a59583 meta: remove (de)serialize functions
Add a GType to the metadata to identify the GstMetaInfo.
We can remove the (de)serialize functions for the metadata because we can
register GTtype transform functions between various types to implement
serialization later.
2011-05-11 19:10:24 +02:00

152 lines
4.1 KiB
C

/* GStreamer
* Copyright (C) 2011 Wim Taymans <wim.taymans@gmail.com>
*
* gstmeta.c: metadata operations
*
* 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.
*/
/**
* SECTION:gstmeta
* @short_description: Buffer metadata
*
* Last reviewed on December 17th, 2009 (0.10.26)
*/
#include "gst_private.h"
#include "gstbuffer.h"
#include "gstmeta.h"
#include "gstinfo.h"
#include "gstutils.h"
static GHashTable *metainfo = NULL;
static GStaticRWLock lock = G_STATIC_RW_LOCK_INIT;
void
_gst_meta_init (void)
{
metainfo = g_hash_table_new (g_str_hash, g_str_equal);
}
/**
* gst_meta_register_info:
* @info: a #GstMetaInfo
*
* Register a #GstMetaInfo. The same @info can be retrieved later with
* gst_meta_get_info() by using @impl as the key.
*
* Returns: a #GstMetaInfo that can be used to access metadata.
*/
const GstMetaInfo *
gst_meta_register (const gchar * api, const gchar * impl, gsize size,
GstMetaInitFunction init_func, GstMetaFreeFunction free_func,
GstMetaCopyFunction copy_func, GstMetaTransformFunction transform_func)
{
GstMetaInfo *info;
g_return_val_if_fail (api != NULL, NULL);
g_return_val_if_fail (impl != NULL, NULL);
g_return_val_if_fail (size != 0, NULL);
info = g_slice_new (GstMetaInfo);
info->api = g_quark_from_string (api);
info->type = g_pointer_type_register_static (impl);
info->size = size;
info->init_func = init_func;
info->free_func = free_func;
info->copy_func = copy_func;
info->transform_func = transform_func;
GST_DEBUG ("register \"%s\" implementing \"%s\" of size %" G_GSIZE_FORMAT,
api, impl, size);
g_static_rw_lock_writer_lock (&lock);
g_hash_table_insert (metainfo, (gpointer) impl, (gpointer) info);
g_static_rw_lock_writer_unlock (&lock);
return info;
}
/**
* gst_meta_get_info:
* @impl: the name
*
* Lookup a previously registered meta info structure by its implementor name
* @impl.
*
* Returns: a #GstMetaInfo with @impl or #NULL when no such metainfo
* exists.
*/
const GstMetaInfo *
gst_meta_get_info (const gchar * impl)
{
GstMetaInfo *info;
g_return_val_if_fail (impl != NULL, NULL);
g_static_rw_lock_reader_lock (&lock);
info = g_hash_table_lookup (metainfo, impl);
g_static_rw_lock_reader_unlock (&lock);
return info;
}
/* Timing metadata */
static void
meta_timing_copy (GstBuffer * copybuf, GstMetaTiming * meta,
GstBuffer * buffer, gsize offset, gsize size)
{
GstMetaTiming *timing;
GST_DEBUG ("trans called from buffer %p to %p, meta %p, %u-%u", buffer,
copybuf, meta, offset, size);
timing = gst_buffer_add_meta_timing (copybuf);
if (offset == 0) {
/* same offset, copy timestamps */
timing->pts = meta->pts;
timing->dts = meta->dts;
if (size == gst_buffer_get_size (buffer)) {
/* same size, copy duration */
timing->duration = meta->duration;
} else {
/* else clear */
timing->duration = GST_CLOCK_TIME_NONE;
}
} else {
timing->pts = -1;
timing->dts = -1;
timing->duration = -1;
}
timing->clock_rate = meta->clock_rate;
}
const GstMetaInfo *
gst_meta_timing_get_info (void)
{
static const GstMetaInfo *meta_info = NULL;
if (meta_info == NULL) {
meta_info = gst_meta_register ("GstMetaTiming", "GstMetaTiming",
sizeof (GstMetaTiming),
(GstMetaInitFunction) NULL,
(GstMetaFreeFunction) NULL,
(GstMetaCopyFunction) meta_timing_copy,
(GstMetaTransformFunction) NULL);
}
return meta_info;
}