gst/gdp/dataprotocol.h

   1 /* GStreamer
   2  * Copyright (C) 1999 Erik Walthinsen <omega@cse.ogi.edu>
   3  * Copyright (C) 2004,2006 Thomas Vander Stichele <thomas at apestaart dot org>
   4  *
   5  * dataprotocol.h: Functions implementing the GStreamer Data Protocol
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Library General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Library General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Library General Public
  18  * License along with this library; if not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  */
  22
  23 #ifndef __GST_DATA_PROTOCOL_H__
  24 #define __GST_DATA_PROTOCOL_H__
  25
  26 #include <gst/gstbuffer.h>
  27 #include <gst/gstevent.h>
  28 #include <gst/gstcaps.h>
  29
  30 G_BEGIN_DECLS
  31
  32 /**
  33  * GstDPVersion:
  34  * @GST_DP_VERSION_0_2: protocol version 0.2
  35  * @GST_DP_VERSION_1_0: protocol version 1.0
  36  *
  37  * The version of the GDP protocol being used.
  38  */
  39 typedef enum {
  40   GST_DP_VERSION_0_2 = 1,
  41   GST_DP_VERSION_1_0,
  42 } GstDPVersion;
  43
  44 GType gst_dp_version_get_type (void);
  45 #define GST_TYPE_DP_VERSION (gst_dp_version_get_type ())
  46
  47 /**
  48  * GST_DP_VERSION_MAJOR:
  49  *
  50  * The major version number of the GStreamer Data Protocol.
  51  */
  52 #define GST_DP_VERSION_MAJOR 0
  53 /**
  54  * GST_DP_VERSION_MINOR:
  55  *
  56  * The minor version number of the GStreamer Data Protocol.
  57  */
  58 #define GST_DP_VERSION_MINOR 2
  59
  60 /**
  61  * GST_DP_HEADER_LENGTH:
  62  *
  63  * The header size in bytes.
  64  */
  65 #define GST_DP_HEADER_LENGTH 62
  66
  67 /**
  68  * GstDPHeaderFlag:
  69  * @GST_DP_HEADER_FLAG_NONE: No flag present.
  70  * @GST_DP_HEADER_FLAG_CRC_HEADER: a header CRC field is present.
  71  * @GST_DP_HEADER_FLAG_CRC_PAYLOAD: a payload CRC field is present.
  72  * @GST_DP_HEADER_FLAG_CRC: a CRC for header and payload is present.
  73  *
  74  * header flags for the dataprotocol.
  75  */
  76 typedef enum {
  77   GST_DP_HEADER_FLAG_NONE        = 0,
  78   GST_DP_HEADER_FLAG_CRC_HEADER  = (1 << 0),
  79   GST_DP_HEADER_FLAG_CRC_PAYLOAD = (1 << 1),
  80   GST_DP_HEADER_FLAG_CRC         = (1 << 1) | (1 << 0),
  81 } GstDPHeaderFlag;
  82
  83 /**
  84  * GstDPPayloadType:
  85  * @GST_DP_PAYLOAD_NONE: Invalid payload type.
  86  * @GST_DP_PAYLOAD_BUFFER: #GstBuffer payload packet.
  87  * @GST_DP_PAYLOAD_CAPS: #GstCaps payload packet.
  88  * @GST_DP_PAYLOAD_EVENT_NONE: First value of #GstEvent payload packets.
  89  *
  90  * The GDP payload types. a #GstEvent payload type is encoded with the
  91  * event type number starting from @GST_DP_PAYLOAD_EVENT_NONE.
  92  */
  93 typedef enum {
  94   GST_DP_PAYLOAD_NONE            = 0,
  95   GST_DP_PAYLOAD_BUFFER,
  96   GST_DP_PAYLOAD_CAPS,
  97   GST_DP_PAYLOAD_EVENT_NONE      = 64,
  98 } GstDPPayloadType;
  99
 100 typedef gboolean (*GstDPHeaderFromBufferFunction) (const GstBuffer * buffer,
 101                                                 GstDPHeaderFlag flags,
 102                                                 guint * length,
 103                                                 guint8 ** header);
 104 typedef gboolean (*GstDPPacketFromCapsFunction) (const GstCaps * caps,
 105                                                 GstDPHeaderFlag flags,
 106                                                 guint * length,
 107                                                 guint8 ** header,
 108                                                 guint8 ** payload);
 109 typedef gboolean (*GstDPPacketFromEventFunction) (const GstEvent * event,
 110                                                 GstDPHeaderFlag flags,
 111                                                 guint * length,
 112                                                 guint8 ** header,
 113                                                 guint8 ** payload);
 114 typedef struct {
 115   GstDPVersion version;
 116
 117   GstDPHeaderFromBufferFunction header_from_buffer;
 118   GstDPPacketFromCapsFunction packet_from_caps;
 119   GstDPPacketFromEventFunction packet_from_event;
 120
 121   /*< private >*/
 122   gpointer _gst_reserved[GST_PADDING];
 123 } GstDPPacketizer;
 124
 125
 126 void            gst_dp_init                     (void);
 127
 128 /* packetizer */
 129 GstDPPacketizer *
 130                 gst_dp_packetizer_new           (GstDPVersion version);
 131 void            gst_dp_packetizer_free          (GstDPPacketizer *packetizer);
 132
 133 /* crc checksum */
 134 guint16         gst_dp_crc                      (const guint8 * buffer,
 135                                                  guint length);
 136
 137 /* payload information from header */
 138 guint32         gst_dp_header_payload_length    (const guint8 * header);
 139 GstDPPayloadType
 140                 gst_dp_header_payload_type      (const guint8 * header);
 141
 142 /* converting from GstBuffer/GstEvent/GstCaps */
 143 #ifndef GST_DISABLE_DEPRECATED
 144 gboolean        gst_dp_header_from_buffer       (const GstBuffer * buffer,
 145                                                 GstDPHeaderFlag flags,
 146                                                 guint * length,
 147                                                 guint8 ** header);
 148 #endif
 149 #ifndef GST_DISABLE_DEPRECATED
 150 gboolean        gst_dp_packet_from_caps         (const GstCaps * caps,
 151                                                 GstDPHeaderFlag flags,
 152                                                 guint * length,
 153                                                 guint8 ** header,
 154                                                 guint8 ** payload);
 155 #endif
 156 #ifndef GST_DISABLE_DEPRECATED
 157 gboolean        gst_dp_packet_from_event        (const GstEvent * event,
 158                                                 GstDPHeaderFlag flags,
 159                                                 guint * length,
 160                                                 guint8 ** header,
 161                                                 guint8 ** payload);
 162 #endif
 163 /* converting to GstBuffer/GstEvent/GstCaps */
 164 GstBuffer *     gst_dp_buffer_from_header       (guint header_length,
 165                                                 const guint8 * header);
 166 GstCaps *       gst_dp_caps_from_packet         (guint header_length,
 167                                                 const guint8 * header,
 168                                                 const guint8 * payload);
 169 GstEvent *      gst_dp_event_from_packet        (guint header_length,
 170                                                 const guint8 * header,
 171                                                 const guint8 * payload);
 172
 173 /* validation */
 174 gboolean        gst_dp_validate_header          (guint header_length,
 175                                                 const guint8 * header);
 176 gboolean        gst_dp_validate_payload         (guint header_length,
 177                                                 const guint8 * header,
 178                                                 const guint8 * payload);
 179 gboolean        gst_dp_validate_packet          (guint header_length,
 180                                                 const guint8 * header,
 181                                                 const guint8 * payload);
 182
 183 G_END_DECLS
 184
 185 #endif /* __GST_DATA_PROTOCOL_H__ */
 186