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|
/* packet-h263.c
*
* Routines for ITU-T Recommendation H.263 dissection
*
* Copyright 2003 Niklas Ögren <niklas.ogren@7l.se>
* Seven Levels Consultants AB
*
* $Id: packet-h263.c,v 1.1 2003/08/23 04:19:22 sahlberg Exp $
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@ethereal.com>
* Copyright 1998 Gerald Combs
*
* Copied structure from packet-h261.c
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/*
* This dissector tries to dissect the H.263 protocol according to
* ITU-T Recommendations and RFC 2190
*
* This dissector is called by the RTP dissector
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <glib.h>
#include <epan/packet.h>
#include <stdio.h>
#include <string.h>
/* H.263 header fields */
static int proto_h263 = -1;
/* Mode A header */
static int hf_h263_ftype = -1;
static int hf_h263_pbframes = -1;
static int hf_h263_sbit = -1;
static int hf_h263_ebit = -1;
static int hf_h263_srcformat = -1;
static int hf_h263_picture_coding_type = -1;
static int hf_h263_unrestricted_motion_vector = -1;
static int hf_h263_syntax_based_arithmetic = -1;
static int hf_h263_advanced_prediction = -1;
/*static int hf_h263_reserved = -1;*/
static int hf_h263_dbq = -1;
static int hf_h263_trb = -1;
static int hf_h263_tr = -1;
/* Additional fields for Mode B or C header */
static int hf_h263_quant = -1;
static int hf_h263_gobn = -1;
static int hf_h263_mba = -1;
static int hf_h263_hmv1 = -1;
static int hf_h263_vmv1 = -1;
static int hf_h263_hmv2 = -1;
static int hf_h263_vmv2 = -1;
static int hf_h263_data = -1;
/* Source format types */
#define SRCFORMAT_FORB 0 /* forbidden */
#define SRCFORMAT_SQCIF 1
#define SRCFORMAT_QCIF 2
#define SRCFORMAT_CIF 3
#define SRCFORMAT_4CIF 4
#define SRCFORMAT_16CIF 5
static const value_string srcformat_vals[] =
{
{ SRCFORMAT_FORB, "forbidden" },
{ SRCFORMAT_SQCIF, "sub-QCIF 128x96" },
{ SRCFORMAT_QCIF, "QCIF 176x144" },
{ SRCFORMAT_CIF, "CIF 352x288" },
{ SRCFORMAT_4CIF, "4CIF 704x576" },
{ SRCFORMAT_16CIF, "16CIF 1408x1152" },
{ 0, NULL },
};
/* H.263 fields defining a sub tree */
static gint ett_h263 = -1;
static void
dissect_h263( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
{
proto_item *ti = NULL;
proto_tree *h263_tree = NULL;
unsigned int offset = 0;
unsigned int h263_version = 0;
h263_version = (tvb_get_guint8( tvb, offset ) & 0xc0 ) >> 6;
if ( check_col( pinfo->cinfo, COL_PROTOCOL ) ) {
col_set_str( pinfo->cinfo, COL_PROTOCOL, "H.263" );
}
if( h263_version == 0x00) {
if ( check_col( pinfo->cinfo, COL_INFO) ) {
col_append_str( pinfo->cinfo, COL_INFO, " MODE A");
}
}
else if( h263_version == 0x02) {
if ( check_col( pinfo->cinfo, COL_INFO) ) {
col_append_str( pinfo->cinfo, COL_INFO, " MODE B");
}
}
else if( h263_version == 0x03) {
if ( check_col( pinfo->cinfo, COL_INFO) ) {
col_append_str( pinfo->cinfo, COL_INFO, " MODE C");
}
}
if ( tree ) {
ti = proto_tree_add_item( tree, proto_h263, tvb, offset, -1, FALSE );
h263_tree = proto_item_add_subtree( ti, ett_h263 );
/* FBIT 1st octet, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_ftype, tvb, offset, 1, tvb_get_guint8( tvb, offset ) >> 7 );
/* PBIT 1st octet, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_pbframes, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 1 ) >> 7 );
/* SBIT 1st octet, 3 bits */
proto_tree_add_uint( h263_tree, hf_h263_sbit, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 2 ) >> 5 );
/* EBIT 1st octet, 3 bits */
proto_tree_add_uint( h263_tree, hf_h263_ebit, tvb, offset, 1, tvb_get_guint8( tvb, offset ) & 0x7 );
offset++;
/* SRC 2nd octet, 3 bits */
proto_tree_add_uint( h263_tree, hf_h263_srcformat, tvb, offset, 1, tvb_get_guint8( tvb, offset ) >> 5 );
if(h263_version == 0x00) { /* MODE A */
/* I flag, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_picture_coding_type, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 3 ) >>7 );
/* U flag, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_unrestricted_motion_vector, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 4 ) >>7 );
/* S flag, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_syntax_based_arithmetic, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 5 ) >>7 );
/* A flag, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_advanced_prediction, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 6 ) >>7 );
offset++;
/* DBQ 3 octect, 2 bits */
proto_tree_add_uint( h263_tree, hf_h263_dbq, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 3 ) >>6 );
/* TRB 3 octect, 3 bits */
proto_tree_add_uint( h263_tree, hf_h263_trb, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 5 ) >>5 );
offset++;
/* TR 4 octect, 8 bits */
proto_tree_add_uint( h263_tree, hf_h263_tr, tvb, offset, 1, tvb_get_guint8( tvb, offset ) );
} else { /* MODE B or MODE C */
/* QUANT 2 octect, 5 bits */
proto_tree_add_uint( h263_tree, hf_h263_quant, tvb, offset, 1, tvb_get_guint8( tvb, offset ) & 0x1f );
offset++;
/* GOBN 3 octect, 5 bits */
proto_tree_add_uint( h263_tree, hf_h263_gobn, tvb, offset, 1, tvb_get_guint8( tvb, offset ) >> 3);
/* MBA 3 octect, 3 bits + 4 octect 6 bits */
proto_tree_add_uint( h263_tree, hf_h263_mba, tvb, offset, 2, ( ( tvb_get_guint8( tvb, offset ) & 0x7 ) << 6 ) + ( tvb_get_guint8( tvb, offset + 1 ) >> 2 ) );
offset++;
/* I flag, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_picture_coding_type, tvb, offset, 1, tvb_get_guint8( tvb, offset ) >>7 );
/* U flag, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_unrestricted_motion_vector, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 1 ) >>7 );
/* S flag, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_syntax_based_arithmetic, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 2 ) >>7 );
/* A flag, 1 bit */
proto_tree_add_boolean( h263_tree, hf_h263_advanced_prediction, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 3 ) >>7 );
/* HMV1 5th octect, 4 bits + 6th octect 3 bits*/
proto_tree_add_uint( h263_tree, hf_h263_hmv1, tvb, offset, 2,( ( tvb_get_guint8( tvb, offset ) & 0xf ) << 3 ) + ( tvb_get_guint8( tvb, offset+1 ) >> 5));
offset++;
/* VMV1 6th octect, 5 bits + 7th octect 2 bits*/
proto_tree_add_uint( h263_tree, hf_h263_vmv1, tvb, offset, 2,( ( tvb_get_guint8( tvb, offset ) & 0x1f ) << 2 ) + ( tvb_get_guint8( tvb, offset+1 ) >> 6));
offset++;
/* HMV2 7th octect, 6 bits + 8th octect 1 bit*/
proto_tree_add_uint( h263_tree, hf_h263_hmv2, tvb, offset, 2,( ( tvb_get_guint8( tvb, offset ) & 0x3f ) << 1 ) + ( tvb_get_guint8( tvb, offset+1 ) >> 7));
offset++;
/* VMV2 8th octect, 7 bits*/
proto_tree_add_uint( h263_tree, hf_h263_vmv2, tvb, offset, 1, tvb_get_guint8( tvb, offset ) & 0x7f );
if(h263_version == 0x03) { /* MODE C */
offset+=3;
/* DBQ 11th octect, 2 bits */
proto_tree_add_uint( h263_tree, hf_h263_dbq, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 3 ) >>6 );
/* TRB 11th octect, 3 bits */
proto_tree_add_uint( h263_tree, hf_h263_trb, tvb, offset, 1, ( tvb_get_guint8( tvb, offset ) << 5 ) >>5 );
offset++;
/* TR 12th octect, 8 bits */
proto_tree_add_uint( h263_tree, hf_h263_tr, tvb, offset, 1, tvb_get_guint8( tvb, offset ) );
} /* end mode c */
} /* end not mode a */
/* The rest of the packet is the H.263 stream */
proto_tree_add_item( h263_tree, hf_h263_data, tvb, offset, -1, FALSE );
}
}
void
proto_register_h263(void)
{
static hf_register_info hf[] =
{
{
&hf_h263_ftype,
{
"MODE B or C",
"h263.sbit",
FT_BOOLEAN,
BASE_NONE,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_pbframes,
{
"p/b frame flag (MODE C)",
"h263.pbframes",
FT_BOOLEAN,
BASE_NONE,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_sbit,
{
"Start bit position",
"h263.sbit",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_ebit,
{
"End bit position",
"h263.ebit",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_srcformat,
{
"Video Format",
"h263.srcformat",
FT_UINT8,
BASE_DEC,
VALS(srcformat_vals),
0x0,
"", HFILL
}
},
{
&hf_h263_picture_coding_type,
{
"Intra frame encoded data flag",
"h263.picture_coding_type",
FT_BOOLEAN,
BASE_NONE,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_unrestricted_motion_vector,
{
"Motion vector flag",
"h263.unrestricted_motion_vector",
FT_BOOLEAN,
BASE_NONE,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_syntax_based_arithmetic,
{
"Syntax-based arithmetic coding",
"h263.syntax_based_arithmetic",
FT_BOOLEAN,
BASE_NONE,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_advanced_prediction,
{
"Advanced prediction option",
"h263.advanced_prediction",
FT_BOOLEAN,
BASE_NONE,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_dbq,
{
"Differential quantization parameter",
"h263.dbq",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_trb,
{
"Temporal Reference for B frames",
"h263.trb",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_tr,
{
"Temporal reference for P frames",
"h263.tr",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_quant,
{
"Quantizer",
"h263.quant",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_gobn,
{
"GOB Number",
"h263.gobn",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_mba,
{
"Macroblock address",
"h263.mba",
FT_UINT16,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_hmv1,
{
"Horizontal motion vector data 1",
"h263.hmv1",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_vmv1,
{
"Vertical motion vector data 1",
"h263.vmv1",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_hmv2,
{
"Horizontal motion vector data 2",
"h263.hmv2",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_vmv2,
{
"Vertical motion vector data 2",
"h263.vmv2",
FT_UINT8,
BASE_DEC,
NULL,
0x0,
"", HFILL
}
},
{
&hf_h263_data,
{
"H.263 stream",
"h263.stream",
FT_BYTES,
BASE_NONE,
NULL,
0x0,
"", HFILL
}
},
};
static gint *ett[] =
{
&ett_h263,
};
proto_h263 = proto_register_protocol("ITU-T Recommendation H.263 RTP Payload header (RFC2190)",
"H.263", "h263");
proto_register_field_array(proto_h263, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
register_dissector("h263", dissect_h263, proto_h263);
}
|
