gstreamer/libs/gst/dataprotocol/dataprotocol.h
2010-12-06 19:40:03 +01:00

165 lines
4.9 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, 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
/**
* GstDPVersion:
* @GST_DP_VERSION_0_2: protocol version 0.2
* @GST_DP_VERSION_1_0: protocol version 1.0
*
* The version of the GDP protocol being used.
*/
typedef enum {
GST_DP_VERSION_0_2 = 1,
GST_DP_VERSION_1_0,
} GstDPVersion;
GType gst_dp_version_get_type (void);
#define GST_TYPE_DP_VERSION (gst_dp_version_get_type ())
/**
* GST_DP_VERSION_MAJOR:
*
* The major version number of the GStreamer Data Protocol.
*/
#define GST_DP_VERSION_MAJOR 0
/**
* GST_DP_VERSION_MINOR:
*
* The minor version number of the GStreamer Data Protocol.
*/
#define GST_DP_VERSION_MINOR 2
/**
* 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;
typedef gboolean (*GstDPHeaderFromBufferFunction) (const GstBuffer * buffer,
GstDPHeaderFlag flags,
guint * length,
guint8 ** header);
typedef gboolean (*GstDPPacketFromCapsFunction) (const GstCaps * caps,
GstDPHeaderFlag flags,
guint * length,
guint8 ** header,
guint8 ** payload);
typedef gboolean (*GstDPPacketFromEventFunction) (const GstEvent * event,
GstDPHeaderFlag flags,
guint * length,
guint8 ** header,
guint8 ** payload);
typedef struct {
GstDPVersion version;
GstDPHeaderFromBufferFunction header_from_buffer;
GstDPPacketFromCapsFunction packet_from_caps;
GstDPPacketFromEventFunction packet_from_event;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
} GstDPPacketizer;
void gst_dp_init (void);
/* packetizer */
GstDPPacketizer *
gst_dp_packetizer_new (GstDPVersion version);
void gst_dp_packetizer_free (GstDPPacketizer *packetizer);
/* crc checksum */
guint16 gst_dp_crc (const guint8 * buffer,
guint length);
/* 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);
/* 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__ */