gstreamer/gst/gdp/dataprotocol.h
Tim-Philipp Müller 62294f0650 gdppay: refactor payloading code a little
Get rid of some indirections and inefficiencies,
just payload things directly which gives us more
control over what memory is allocated where and
how and makes things much simpler. In particular,
we can now allocate the payload header plus the
GstMemory to represent it in one go.
2014-12-26 13:44:33 +00:00

111 lines
4.2 KiB
C

/* GStreamer
* Copyright (C) 1999 Erik Walthinsen <omega@cse.ogi.edu>
* Copyright (C) 2004,2006 Thomas Vander Stichele <thomas at apestaart dot org>
*
* dataprotocol.h: Functions implementing the GStreamer Data Protocol
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef __GST_DATA_PROTOCOL_H__
#define __GST_DATA_PROTOCOL_H__
#include <gst/gstbuffer.h>
#include <gst/gstevent.h>
#include <gst/gstcaps.h>
G_BEGIN_DECLS
/**
* GST_DP_HEADER_LENGTH:
*
* The header size in bytes.
*/
#define GST_DP_HEADER_LENGTH 62
/**
* GstDPHeaderFlag:
* @GST_DP_HEADER_FLAG_NONE: No flag present.
* @GST_DP_HEADER_FLAG_CRC_HEADER: a header CRC field is present.
* @GST_DP_HEADER_FLAG_CRC_PAYLOAD: a payload CRC field is present.
* @GST_DP_HEADER_FLAG_CRC: a CRC for header and payload is present.
*
* header flags for the dataprotocol.
*/
typedef enum {
GST_DP_HEADER_FLAG_NONE = 0,
GST_DP_HEADER_FLAG_CRC_HEADER = (1 << 0),
GST_DP_HEADER_FLAG_CRC_PAYLOAD = (1 << 1),
GST_DP_HEADER_FLAG_CRC = (1 << 1) | (1 << 0),
} GstDPHeaderFlag;
/**
* GstDPPayloadType:
* @GST_DP_PAYLOAD_NONE: Invalid payload type.
* @GST_DP_PAYLOAD_BUFFER: #GstBuffer payload packet.
* @GST_DP_PAYLOAD_CAPS: #GstCaps payload packet.
* @GST_DP_PAYLOAD_EVENT_NONE: First value of #GstEvent payload packets.
*
* The GDP payload types. a #GstEvent payload type is encoded with the
* event type number starting from @GST_DP_PAYLOAD_EVENT_NONE.
*/
typedef enum {
GST_DP_PAYLOAD_NONE = 0,
GST_DP_PAYLOAD_BUFFER,
GST_DP_PAYLOAD_CAPS,
GST_DP_PAYLOAD_EVENT_NONE = 64,
} GstDPPayloadType;
void gst_dp_init (void);
/* payload information from header */
guint32 gst_dp_header_payload_length (const guint8 * header);
GstDPPayloadType
gst_dp_header_payload_type (const guint8 * header);
/* converting to GstBuffer/GstEvent/GstCaps */
GstBuffer * gst_dp_buffer_from_header (guint header_length,
const guint8 * header);
GstCaps * gst_dp_caps_from_packet (guint header_length,
const guint8 * header,
const guint8 * payload);
GstEvent * gst_dp_event_from_packet (guint header_length,
const guint8 * header,
const guint8 * payload);
/* payloading GstBuffer/GstEvent/GstCaps */
GstBuffer * gst_dp_payload_buffer (GstBuffer * buffer,
GstDPHeaderFlag flags);
GstBuffer * gst_dp_payload_caps (const GstCaps * caps,
GstDPHeaderFlag flags);
GstBuffer * gst_dp_payload_event (const GstEvent * event,
GstDPHeaderFlag flags);
/* validation */
gboolean gst_dp_validate_header (guint header_length,
const guint8 * header);
gboolean gst_dp_validate_payload (guint header_length,
const guint8 * header,
const guint8 * payload);
gboolean gst_dp_validate_packet (guint header_length,
const guint8 * header,
const guint8 * payload);
G_END_DECLS
#endif /* __GST_DATA_PROTOCOL_H__ */