epan/dissectors/packet-mp4ves.c

   1 /*
   2  * packet-mp4ves.c
   3  * Routines for MPEG4 dissection
   4  * Copyright 2007-2008, Anders Broman <anders.broman[at]ericsson.com>
   5  *
   6  * $Id$
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  25  *
  26  * References:
  27  * http://www.ietf.org/rfc/rfc3016.txt?number=3016
  28  */
  29
  30 #ifdef HAVE_CONFIG_H
  31 # include "config.h"
  32 #endif
  33
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37
  38 #include <glib.h>
  39
  40 #include <epan/packet.h>
  41 #include <epan/proto.h>
  42 #include <epan/asn1.h>
  43
  44 #include "prefs.h"
  45
  46 /* Initialize the protocol and registered fields */
  47 static int proto_mp4ves                                                         = -1;
  48
  49 static int hf_mp4ves_config = -1;
  50 static int hf_mp4ves_start_code_prefix = -1;
  51 static int hf_mp4ves_start_code = -1;
  52 static int hf_mp4ves_vop_coding_type = -1;
  53 static int hf_mp4ves_profile_and_level_indication = -1;
  54 static int hf_mp4ves_is_visual_object_identifier = -1;
  55 static int hf_mp4ves_visual_object_type = -1;
  56 static int hf_mp4ves_video_signal_type = -1;
  57 static int hf_mp4ves_stuffing = -1;
  58 static int hf_mp4ves_video_object_type_indication = -1;
  59 static int hf_mp4ves_random_accessible_vol = -1;
  60 static int hf_mp4ves_is_object_layer_identifier = -1;
  61 static int hf_mp4ves_aspect_ratio_info = -1;
  62 static int hf_mp4ves_vol_control_parameters = -1;
  63 static int hf_mp4ves_video_object_layer_shape = -1;
  64
  65 /* Initialize the subtree pointers */
  66 static int ett_mp4ves = -1;
  67 static int ett_mp4ves_config = -1;
  68
  69 /* The dynamic payload type which will be dissected as MP4V-ES */
  70
  71 static guint global_dynamic_payload_type = 0;
  72
  73
  74 /*
  75 14496-2, Annex G, Table G-1.
  76 Table G-1 FLC table for profile_and_level_indication Profile/Level Code
  77 */
  78 const value_string mp4ves_level_indication_vals[] =
  79 {
  80         { 0,    "Reserved" },
  81         { 1,    "Simple Profile/Level 1" },
  82         { 2,    "Simple Profile/Level 2" },
  83         { 3,    "Reserved" },
  84         { 4,    "Reserved" },
  85         { 5,    "Reserved" },
  86         { 6,    "Reserved" },
  87         { 7,    "Reserved" },
  88         { 8,    "Simple Profile/Level 0" },
  89         { 9,    "Simple Profile/Level 0b" },
  90         /* Reserved 00001001 - 00010000 */
  91         { 0x11, "Simple Scalable Profile/Level 1" },
  92         { 0x12, "Simple Scalable Profile/Level 2" },
  93         /* Reserved 00010011 - 00100000 */
  94         { 0x21, "Core Profile/Level 1" },
  95         { 0x22, "Core Profile/Level 2" },
  96         /* Reserved 00100011 - 00110001 */
  97         { 0x32, "Main Profile/Level 2" },
  98         { 0x33, "Main Profile/Level 3" },
  99         { 0x34, "Main Profile/Level 4" },
 100         /* Reserved 00110101 - 01000001  */
 101         { 0x42, "N-bit Profile/Level 2" },
 102         /* Reserved 01000011 - 01010000  */
 103         { 0x51, "Scalable Texture Profile/Level 1" },
 104         /* Reserved 01010010 - 01100000 */
 105         { 0x61, "Simple Face Animation Profile/Level 1" },
 106         { 0x62, "Simple Face Animation Profile/Level 2" },
 107         { 0x63, "Simple FBA Profile/Level 1" },
 108         { 0x64, "Simple FBA Profile/Level 2" },
 109         /* Reserved 01100101 - 01110000 */
 110         { 0x71, "Basic Animated Texture Profile/Level 1" },
 111         { 0x72, "Basic Animated Texture Profile/Level 2" },
 112         /* Reserved 01110011 - 10000000 */
 113         { 0x81, "Hybrid Profile/Level 1" },
 114         { 0x82, "Hybrid Profile/Level 2" },
 115         /* Reserved 10000011 - 10010000 */
 116         { 0x91, "Advanced Real Time Simple Profile/Level 1" },
 117         { 0x92, "Advanced Real Time Simple Profile/Level 2" },
 118         { 0x93, "Advanced Real Time Simple Profile/Level 3" },
 119         { 0x94, "Advanced Real Time Simple Profile/Level 4" },
 120         /* Reserved 10010101 - 10100000 */
 121         { 0xa1, "Core Scalable Profile/Level 1" },
 122         { 0xa2, "Core Scalable Profile/Level 2" },
 123         { 0xa3, "Core Scalable Profile/Level 3" },
 124         /* Reserved 10100100 - 10110000  */
 125         { 0xb1, "Advanced Coding Efficiency Profile/Level 1" },
 126         { 0xb2, "Advanced Coding Efficiency Profile/Level 2" },
 127         { 0xb3, "Advanced Coding Efficiency Profile/Level 3" },
 128         { 0xb4, "Advanced Coding Efficiency Profile/Level 4" },
 129         /* Reserved 10110101 - 11000000 */
 130         { 0xc1, "Advanced Core Profile/Level 1" },
 131         { 0xc2, "Advanced Core Profile/Level 2" },
 132         /* Reserved 11000011 - 11010000 */
 133         { 0xd1, "Advanced Scalable Texture/Level 1" },
 134         { 0xd2, "Advanced Scalable Texture/Level 2" },
 135         { 0xd3, "Advanced Scalable Texture/Level 3" },
 136         /* Reserved 11010100 - 11100000 */
 137         { 0xe1, "Simple Studio Profile/Level 1" },
 138         { 0xe2, "Simple Studio Profile/Level 2" },
 139         { 0xe3, "Simple Studio Profile/Level 3" },
 140         { 0xe4, "Simple Studio Profile/Level 4" },
 141         { 0xe5, "Core Studio Profile/Level 1" },
 142         { 0xe6, "Core Studio Profile/Level 2" },
 143         { 0xe7, "Core Studio Profile/Level 3" },
 144         { 0xe8, "Core Studio Profile/Level 4" },
 145         /* Reserved 11101001 - 11101111 */
 146         { 0xf0, "Advanced Simple Profile/Level 0" },
 147         { 0xf1, "Advanced Simple Profile/Level 1" },
 148         { 0xf2, "Advanced Simple Profile/Level 2" },
 149         { 0xf3, "Advanced Simple Profile/Level 3" },
 150         { 0xf4, "Advanced Simple Profile/Level 4" },
 151         { 0xf5, "Advanced Simple Profile/Level 5" },
 152         /* Reserved 11110110 - 11110111 */
 153         { 0xf8, "Fine Granularity Scalable Profile/Level 0" },
 154         { 0xf9, "Fine Granularity Scalable Profile/Level 1" },
 155         { 0xfa, "Fine Granularity Scalable Profile/Level 2" },
 156         { 0xfb, "Fine Granularity Scalable Profile/Level 3" },
 157         { 0xfc, "Fine Granularity Scalable Profile/Level 4" },
 158         { 0xfd, "Fine Granularity Scalable Profile/Level 5" },
 159         { 0xfe, "Reserved" },
 160         { 0xff, "Reserved for Escape" },
 161         { 0, NULL },
 162 };
 163 static const range_string mp4ves_startcode_vals[] = {
 164         { 0x00, 0x1f, "video_object_start_code" },
 165         { 0x20, 0x2f, "video_object_layer_start_code" },
 166         { 0x30, 0xaf, "reserved" },
 167         { 0xb0, 0xb0, "visual_object_sequence_start_code" },
 168         { 0xb1, 0xb1, "visual_object_sequence_end_code" },
 169         { 0xb2, 0xb2, "user_data_start_code" },
 170         { 0xb3, 0xb3, "group_of_vop_start_code" },
 171         { 0xb4, 0xb4, "video_session_error_code" },
 172         { 0xb5, 0xb5, "visual_object_start_code" },
 173         { 0xb6, 0xb6, "vop_start_code" },
 174         { 0xb7, 0xb9, "reserved" },
 175         { 0xba, 0xba, "fba_object_start_code" },
 176         { 0xbb, 0xbb, "fba_object_plane_start_code" },
 177         { 0xbc, 0xbc, "mesh_object_start_code" },
 178         { 0xbd, 0xbd, "mesh_object_plane_start_code" },
 179         { 0xbe, 0xbe, "still_texture_object_start_code" },
 180         { 0xbf, 0xbf, "texture_spatial_layer_start_code" },
 181         { 0xc0, 0xc0, "texture_snr_layer_start_code" },
 182         { 0xc1, 0xc1, "texture_tile_start_code" },
 183         { 0xc2, 0xc2, "texture_shape_layer_start_code" },
 184         { 0xc3, 0xc3, "stuffing_start_code" },
 185         { 0xc4, 0xc5, "reserved" },
 186         { 0xc6, 0xcf, "System start codes" }, /* NOTE System start codes are defined in ISO/IEC 14496-1:1999 */
 187         { 0,     0, NULL }
 188 };
 189
 190 static const value_string mp4ves_vop_coding_type_vals[] = {
 191         { 0,    "intra-coded (I)" },
 192         { 1,    "predictive-coded (P)" },
 193         { 2,    "bidirectionally-predictive-coded (B)" },
 194         { 3,    "sprite (S)" },
 195         { 0,    NULL }
 196 };
 197
 198 /*
 199  * FLC table for video_object_type indication
 200  */
 201 static const value_string mp4ves_video_object_type_vals[] = {
 202         { 0x0,  "Reserved" },
 203         { 0x1,  "Simple Object Type" },
 204         { 0x2,  "Simple Scalable Object Type" },
 205         { 0x3,  "Core Object Type" },
 206         { 0x4,  "Main Object Type" },
 207         { 0x5,  "N-bit Object Type" },
 208         { 0x6,  "Basic Anim. 2D Texture" },
 209         { 0x7,  "Anim. 2D Mesh" },
 210         { 0x8,  "Simple Face" },
 211         { 0x9,  "Still Scalable Texture" },
 212         { 0xa,  "Advanced Real Time Simple" },
 213         { 0xb,  "Core Scalable" },
 214         { 0xc,  "Advanced Coding Efficiency" },
 215         { 0xd,  "Advanced Scalable Texture" },
 216         { 0xe,  "Simple FBA" },
 217         { 0,    NULL }
 218 };
 219 /* Visual object type */
 220 static const value_string mp4ves_visual_object_type_vals[] = {
 221         { 0x0,  "reserved" },
 222         { 0x1,  "video ID" },
 223         { 0x2,  "still texture ID" },
 224         { 0x3,  "mesh ID" },
 225         { 0x4,  "FBA ID" },
 226         { 0x5,  "3D mesh ID" },
 227         { 0x6,  "reserved" },
 228         { 0x7,  "reserved" },
 229         { 0x8,  "reserved" },
 230         { 0x9,  "reserved" },
 231         { 0xa,  "reserved" },
 232         { 0xb,  "reserved" },
 233         { 0xc,  "reserved" },
 234         { 0xd,  "reserved" },
 235         { 0xe,  "reserved" },
 236         { 0xf,  "reserved" },
 237         { 0,    NULL }
 238 };
 239
 240 static const value_string mp4ves_video_object_type_indication_vals[] = {
 241         { 0x0,  "Reserved" },
 242         { 0x1,  "Simple Object Type" },
 243         { 0x2,  "Simple Scalable Object Type" },
 244         { 0x3,  "Core Object Type" },
 245         { 0x4,  "Main Object Type" },
 246         { 0x5,  "N-bit Object Type" },
 247         { 0x6,  "Basic Anim. 2D Texture" },
 248         { 0x7,  "Anim. 2D Mesh" },
 249         { 0x8,  "Simple Face" },
 250         { 0x9,  "Still Scalable Texture" },
 251         { 0xa,  "Advanced Real Time Simple" },
 252         { 0xb,  "Core Scalable" },
 253         { 0xc,  "Advanced Coding Efficiency" },
 254         { 0xd,  "Advanced Scalable Texture" },
 255         { 0xe,  "Simple FBA" },
 256         { 0xf,  "Reserved" },
 257         /* Reserved 00001111 - 11111111 */
 258         { 0,    NULL }
 259 };
 260 /* 6.2.2.1 User data */
 261 static int
 262 dissect_mp4ves_user_data(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int bit_offset)
 263 {
 264         int start_bit_offset;
 265
 266         /* user_data_start_code */
 267         proto_tree_add_bits_item(tree, hf_mp4ves_start_code_prefix, tvb, bit_offset, 24, FALSE);
 268         bit_offset+=24;
 269         proto_tree_add_bits_item(tree, hf_mp4ves_start_code, tvb, bit_offset, 8, FALSE);
 270         bit_offset+=8;
 271         start_bit_offset = bit_offset;
 272         /* while( next_bits() != '000 0000 0000 0000 0000 0001') { */
 273         while ( tvb_get_bits32(tvb,bit_offset, 24, FALSE) != 1){
 274                 bit_offset+=8;
 275                 /* user_data 8 bits */
 276         }
 277         proto_tree_add_text(tree, tvb, start_bit_offset>>3, (bit_offset - start_bit_offset)>>2, "User data");
 278
 279         return bit_offset;
 280 }
 281 /*
 282 next_start_code() {
 283 zero_bit
 284 while (!bytealigned())
 285 one_bit
 286 }
 287 */
 288 static int
 289 dissect_mp4ves_next_start_code(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int bit_offset)
 290 {
 291         guint8 zero_bit;
 292         int start_bit_offset;
 293
 294         start_bit_offset = bit_offset;
 295
 296         zero_bit = tvb_get_bits8(tvb,bit_offset,1);
 297         if (zero_bit != 0){
 298                 /* Error */
 299         }
 300         bit_offset++;
 301
 302         /* zero stuffing bits */
 303         if(bit_offset %8 == 0)
 304                 return bit_offset;
 305
 306         while(bit_offset %8 != 0){
 307                 bit_offset++;
 308         }
 309
 310         proto_tree_add_bits_item(tree, hf_mp4ves_stuffing, tvb, start_bit_offset, bit_offset-start_bit_offset, FALSE);
 311
 312         return bit_offset;
 313 }
 314
 315 /*
 316 video_signal_type() {
 317         video_signal_type
 318         if (video_signal_type) {
 319                 video_format 3 uimsbf
 320                 video_range 1 bslbf
 321                 colour_description 1 bslbf
 322                 if (colour_description) {
 323                         colour_primaries 8 uimsbf
 324                         transfer_characteristics 8 uimsbf
 325                         matrix_coefficients 8 uimsbf
 326                 }
 327         }
 328 }
 329 */
 330 static int
 331 dissect_mp4ves_visual_object_type(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int bit_offset)
 332 {
 333         guint8 video_signal_type, colour_description;
 334
 335         video_signal_type = tvb_get_bits8(tvb,bit_offset,1);
 336         proto_tree_add_bits_item(tree, hf_mp4ves_video_signal_type, tvb, bit_offset, 1, FALSE);
 337         bit_offset++;
 338         if (video_signal_type) {
 339                 /* video_format 3 bits */
 340                 bit_offset+=3;
 341                 /* video_range 1 bit */
 342                 bit_offset++;
 343                 /* colour_description 1 bit */
 344                 colour_description = tvb_get_bits8(tvb,bit_offset,1);
 345                 if (colour_description) {
 346                         /* colour_primaries 8 bits */
 347                         bit_offset+=8;
 348                         /* transfer_characteristics 8 bits */
 349                         bit_offset+=8;
 350                         /* matrix_coefficients 8 bits*/
 351                         bit_offset+=8;
 352                 }
 353         }
 354
 355         return bit_offset;
 356 }
 357 /*
 358  * 6.2.3 Video Object Layer
 359  */
 360
 361 /*
 362  * Table 6-12 -- Meaning of pixel aspect ratio
 363  */
 364
 365 static const value_string mp4ves_aspect_ratio_info_vals[] = {
 366         { 0x0,  "reserved" },
 367         { 0x0,  "Forbidden" },
 368         { 0x1,  "1:1 (Square)" },
 369         { 0x2,  "12:11 (625-type for 4:3 picture)" },
 370         { 0x3,  "10:11 (525-type for 4:3 picture)" },
 371         { 0x4,  "16:11 (625-type stretched for 16:9 picture)" },
 372         { 0x5,  "40:33 (525-type stretched for 16:9 picture)" },
 373         { 0x6,  "Reserved" },
 374         { 0x7,  "Reserved" },
 375         { 0x8,  "Reserved" },
 376         { 0x9,  "Reserved" },
 377         { 0xa,  "Reserved" },
 378         { 0xb,  "Reserved" },
 379         { 0xc,  "Reserved" },
 380         { 0xd,  "Reserved" },
 381         { 0xe,  "Reserved" },
 382         { 0xf,  "Extended PAR" },
 383         { 0,    NULL }
 384 };
 385
 386 /* Table 6-14 Video Object Layer shape type */
 387 static const value_string mp4ves_video_object_layer_shape_vals[] = {
 388         { 0x0,  "rectangular" },
 389         { 0x1,  "binary" },
 390         { 0x2,  "binary only" },
 391         { 0x3,  "grayscale" },
 392         { 0,    NULL }
 393 };
 394
 395 static int
 396 dissect_mp4ves_VideoObjectLayer(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int bit_offset)
 397 {
 398         guint32 dword;
 399         int current_bit_offset;
 400         guint8 octet, is_object_layer_identifier, aspect_ratio_info, vol_control_parameters, vbv_parameters;
 401         guint8 video_object_layer_shape, video_object_layer_verid = 0;
 402
 403         /* if(next_bits() == video_object_layer_start_code) { */
 404         dword = tvb_get_bits32(tvb,bit_offset, 24, FALSE);
 405         if (dword != 1){
 406                 return bit_offset;
 407         }
 408         octet = tvb_get_bits8(tvb,bit_offset+24, 8);
 409         if((octet>=0x20)&&(octet<=0x2f)){
 410                 /* Continue */
 411         }else{
 412                 return bit_offset;
 413         }
 414         /* video_object_layer_start_code */
 415         proto_tree_add_bits_item(tree, hf_mp4ves_start_code_prefix, tvb, bit_offset, 24, FALSE);
 416         bit_offset+=24;
 417         proto_tree_add_bits_item(tree, hf_mp4ves_start_code, tvb, bit_offset, 8, FALSE);
 418         bit_offset+= 8;
 419
 420         /* short_video_header = 0 */
 421         /* random_accessible_vol 1 */
 422         proto_tree_add_bits_item(tree, hf_mp4ves_random_accessible_vol, tvb, bit_offset, 1, FALSE);
 423         bit_offset++;
 424         /* video_object_type_indication 8 */
 425         proto_tree_add_bits_item(tree, hf_mp4ves_video_object_type_indication, tvb, bit_offset, 8, FALSE);
 426         bit_offset+= 8;
 427         /* is_object_layer_identifier 1 */
 428         is_object_layer_identifier = tvb_get_bits8(tvb,bit_offset, 1);
 429         proto_tree_add_bits_item(tree, hf_mp4ves_is_object_layer_identifier, tvb, bit_offset, 1, FALSE);
 430         bit_offset++;
 431         if(is_object_layer_identifier) {
 432                 /* video_object_layer_verid 4 uimsbf */
 433                 bit_offset+=4;
 434                 /* video_object_layer_priority 3 uimsbf */
 435                 bit_offset+=3;
 436         }
 437         /* aspect_ratio_info 4 uimsbf */
 438         aspect_ratio_info = tvb_get_bits8(tvb,bit_offset, 1);
 439         proto_tree_add_bits_item(tree, hf_mp4ves_aspect_ratio_info, tvb, bit_offset, 4, FALSE);
 440         if (aspect_ratio_info == 0xf /*"extended_PAR"*/ ) {
 441                 /* par_width 8 uimsbf */
 442                 bit_offset+=8;
 443                 /* par_height 8 uimsbf */
 444                 bit_offset+=8;
 445         }
 446         /* vol_control_parameters 1 bslbf */
 447         /* vol_control_parameters 1 bslbf */
 448         vol_control_parameters = tvb_get_bits8(tvb,bit_offset, 1);
 449         proto_tree_add_bits_item(tree, hf_mp4ves_vol_control_parameters, tvb, bit_offset, 1, FALSE);
 450         bit_offset++;
 451         current_bit_offset = bit_offset;
 452         if (vol_control_parameters) {
 453                 /* chroma_format 2 uimsbf */
 454                 bit_offset+=2;
 455                 /* low_delay 1 uimsbf */
 456                 bit_offset++;
 457                 /* vbv_parameters 1 blsbf */
 458                 vbv_parameters = tvb_get_bits8(tvb,bit_offset, 1);
 459                 bit_offset++;
 460                 if (vbv_parameters) {
 461                         /* first_half_bit_rate 15 uimsbf */
 462                         bit_offset+=15;
 463                         /* marker_bit 1 bslbf */
 464                         bit_offset++;
 465                         /* latter_half_bit_rate 15 uimsbf */
 466                         bit_offset+=15;
 467                         /* marker_bit 1 bslbf */
 468                         bit_offset++;
 469                         /* first_half_vbv_buffer_size 15 uimsbf */
 470                         bit_offset+=15;
 471                         /* marker_bit 1 bslbf */
 472                         bit_offset++;
 473                         /* latter_half_vbv_buffer_size 3 uimsbf */
 474                         bit_offset+=3;
 475                         /* first_half_vbv_occupancy 11 uimsbf */
 476                         bit_offset+=11;
 477                         /* marker_bit 1 blsbf */
 478                         bit_offset++;
 479                         /* latter_half_vbv_occupancy 15 uimsbf */
 480                         bit_offset+=15;
 481                         /* marker_bit 1 blsbf */
 482                         bit_offset++;
 483                 }
 484         }
 485         if(bit_offset-current_bit_offset > 0)
 486                 proto_tree_add_text(tree, tvb, current_bit_offset>>3, (bit_offset+7)>>3, "Not dissected bits");
 487         /* video_object_layer_shape 2 uimsbf */
 488         video_object_layer_shape = tvb_get_bits8(tvb,bit_offset, 2);
 489         proto_tree_add_bits_item(tree, hf_mp4ves_video_object_layer_shape, tvb, bit_offset, 2, FALSE);
 490         bit_offset+=2;
 491         if (video_object_layer_shape == 3/*"grayscale"*/&& video_object_layer_verid != 1){
 492                 /* video_object_layer_shape_extension 4 uimsbf */
 493                 bit_offset+=4;
 494         }
 495         /* marker_bit 1 bslbf */
 496         bit_offset++;
 497         /* vop_time_increment_resolution 16 uimsbf */
 498         bit_offset+=16;
 499         /* marker_bit 1 bslbf */
 500         bit_offset++;
 501         /* fixed_vop_rate 1 bslbf */
 502         bit_offset++;
 503
 504
 505         return bit_offset;
 506 }
 507 /* Visual object */
 508 /*
 509 VisualObject() {
 510         visual_object_start_code
 511         is_visual_object_identifier
 512         if (is_visual_object_identifier) {
 513                 visual_object_verid
 514                 visual_object_priority
 515         }
 516         visual_object_type
 517         if (visual_object_type == "Video ID" || visual_object_type == "still textureID") {
 518                 video_signal_type()
 519         }
 520         next_start_code()
 521         while ( next_bits()== user_data_start_code){
 522                 user_data()
 523         }
 524         if (visual_object_type == "Video ID") {
 525                 video_object_start_code
 526                 VideoObjectLayer()
 527         }
 528         else if (visual_object_type == "still texture ID") {
 529                 StillTextureObject()
 530         }
 531         else if (visual_object_type == "mesh ID") {
 532                 MeshObject()
 533         }
 534         else if (visual_object_type == "FBA ID") {
 535                 FBAObject()
 536         }
 537         else if (visual_object_type == "3D mesh ID") {
 538                 3D_Mesh_Object()
 539         }
 540         if (next_bits() != "0000 0000 0000 0000 0000 0001")
 541                 next_start_code()
 542 }
 543 */
 544 static int
 545 dissect_mp4ves_VisualObject(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int bit_offset)
 546 {
 547         proto_item *item;
 548         guint8 is_visual_object_identifier, visual_object_type;
 549         guint32 dword;
 550         guint8 octet;
 551
 552         is_visual_object_identifier = tvb_get_bits8(tvb,bit_offset,1);
 553         proto_tree_add_bits_item(tree, hf_mp4ves_is_visual_object_identifier, tvb, bit_offset, 1, FALSE);
 554         bit_offset++;
 555         if(is_visual_object_identifier){
 556                 /* visual_object_verid 4 bits*/
 557                 bit_offset+=4;
 558                 /* visual_object_priority 3 bits*/
 559                 bit_offset+=3;
 560         }
 561         /* visual_object_type 4 bits*/
 562         visual_object_type = tvb_get_bits8(tvb,bit_offset,4);
 563         proto_tree_add_bits_item(tree, hf_mp4ves_visual_object_type, tvb, bit_offset, 4, FALSE);
 564         bit_offset+=4;
 565         if ((visual_object_type == 1/*"Video ID"*/) || (visual_object_type == 2/*"still textureID"*/)) {
 566                 /* video_signal_type() */
 567                 bit_offset = dissect_mp4ves_visual_object_type(tvb, pinfo, tree, bit_offset);
 568         }
 569         /* next_start_code() */
 570         bit_offset = dissect_mp4ves_next_start_code(tvb, pinfo, tree, bit_offset);
 571         dword = tvb_get_bits32(tvb,bit_offset, 32, FALSE);
 572 /*
 573         while ( next_bits()== user_data_start_code){
 574                 user_data()
 575         }
 576 */
 577         while(dword==0x1b2){
 578                 bit_offset = dissect_mp4ves_user_data(tvb, pinfo, tree, bit_offset);
 579                 dword = tvb_get_bits32(tvb,bit_offset, 32, FALSE);
 580         }
 581         if (visual_object_type == 1/*"Video ID"*/) {
 582                 /*
 583                  * video_object_start_code
 584                  */
 585                 dword = tvb_get_bits32(tvb,bit_offset, 24, FALSE);
 586                 if (dword != 1){
 587                         /* no start code */
 588                         return -1;
 589                 }
 590                 octet = tvb_get_bits8(tvb,bit_offset+24, 8);
 591                 if(octet>0x20){
 592                         /* Error */
 593                         return -1;
 594                 }
 595                 proto_tree_add_bits_item(tree, hf_mp4ves_start_code_prefix, tvb, bit_offset, 24, FALSE);
 596                 bit_offset+=24;
 597                 proto_tree_add_bits_item(tree, hf_mp4ves_start_code, tvb, bit_offset, 8, FALSE);
 598                 bit_offset+= 8;
 599                 if(tvb_length_remaining(tvb,(bit_offset>>3))==0){
 600                         item = proto_tree_add_text(tree, tvb, 0, -1, "Config string to short");
 601                         PROTO_ITEM_SET_GENERATED(item);
 602                         return -1;
 603                 }
 604                 /*
 605                 VideoObjectLayer()
 606                 */
 607                 bit_offset = dissect_mp4ves_VideoObjectLayer(tvb, pinfo, tree, bit_offset);
 608         }
 609
 610         return bit_offset;
 611 }
 612
 613 static int
 614 dissect_mp4ves_VisualObjectSequence(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int bit_offset)
 615 {
 616         guint32 dword;
 617
 618         /*VisualObjectSequence() {
 619         do {
 620                 visual_object_sequence_start_code
 621         */
 622
 623         /* Get start code prefix */
 624         dword = tvb_get_bits32(tvb,bit_offset, 32, FALSE);
 625         if ((dword & 0x00000100) != 0x00000100){
 626                 /* No start code prefix */
 627                 return -1;
 628         }
 629         proto_tree_add_bits_item(tree, hf_mp4ves_start_code_prefix, tvb, bit_offset, 24, FALSE);
 630         bit_offset+= 24;
 631
 632         proto_tree_add_bits_item(tree, hf_mp4ves_start_code, tvb, bit_offset, 8, FALSE);
 633         bit_offset+= 8;
 634
 635         /* Expect visual_object_sequence_start_code */
 636         if(dword != 0x1b0)
 637                 return -1;
 638         /*      profile_and_level_indication */
 639         proto_tree_add_bits_item(tree, hf_mp4ves_profile_and_level_indication, tvb, bit_offset, 8, FALSE);
 640         bit_offset+= 8;
 641
 642         /*      while ( next_bits()== user_data_start_code){
 643                 user_data()
 644         }
 645         */
 646         dword = tvb_get_bits32(tvb,bit_offset, 32, FALSE);
 647         bit_offset+= 32;
 648         if ((dword & 0x00000100) != 0x00000100){
 649                 /* No start code prefix */
 650                 return -1;
 651         }
 652         if(dword==0x1b2){
 653                 /*
 654                  * user_data_start_code
 655                  * XXX call user data dissection here
 656                  */
 657                 return -1;
 658         }
 659         if(dword==0x1b5){
 660         /*
 661          * VisualObject()
 662          */
 663                 bit_offset = dissect_mp4ves_VisualObject(tvb, pinfo, tree, bit_offset);
 664         }
 665                 /*
 666         } while ( next_bits() != visual_object_sequence_end_code)
 667         visual_object_sequence_end_code
 668         */
 669         return bit_offset;
 670 }
 671
 672 void
 673 dissect_mp4ves_config(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 674 {
 675         proto_item *item;
 676         proto_tree *mp4ves_tree;
 677
 678         item = proto_tree_add_item(tree, hf_mp4ves_config, tvb, 0, -1, FALSE);
 679         mp4ves_tree = proto_item_add_subtree(item, ett_mp4ves_config);
 680
 681         dissect_mp4ves_VisualObjectSequence(tvb, pinfo, tree, 0);
 682 }
 683
 684 void
 685 dissect_mp4ves(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 686 {
 687         int bit_offset = 0;
 688         proto_item *item;
 689         proto_tree *mp4ves_tree;
 690         guint32 dword;
 691
 692         /* Make entries in Protocol column and Info column on summary display */
 693         col_set_str(pinfo->cinfo, COL_PROTOCOL, "MP4V-ES");
 694         if (tree) {
 695                 item = proto_tree_add_item(tree, proto_mp4ves, tvb, 0, -1, FALSE);
 696                 mp4ves_tree = proto_item_add_subtree(item, ett_mp4ves);
 697         /*
 698             +------+------+------+------+
 699         (a) | RTP  |  VS  |  VO  | VOL  |
 700             |header|header|header|header|
 701             +------+------+------+------+
 702
 703             +------+------+------+------+------------+
 704         (b) | RTP  |  VS  |  VO  | VOL  |Video Packet|
 705             |header|header|header|header|            |
 706             +------+------+------+------+------------+
 707
 708             +------+-----+------------------+
 709         (c) | RTP  | GOV |Video Object Plane|
 710             |header|     |                  |
 711             +------+-----+------------------+
 712
 713             +------+------+------------+  +------+------+------------+
 714         (d) | RTP  | VOP  |Video Packet|  | RTP  |  VP  |Video Packet|
 715             |header|header|    (1)     |  |header|header|    (2)     |
 716             +------+------+------------+  +------+------+------------+
 717
 718             +------+------+------------+------+------------+------+------------+
 719         (e) | RTP  |  VP  |Video Packet|  VP  |Video Packet|  VP  |Video Packet|
 720             |header|header|     (1)    |header|    (2)     |header|    (3)     |
 721             +------+------+------------+------+------------+------+------------+
 722
 723            +------+------+------------+  +------+------------+
 724         (f) | RTP  | VOP  |VOP fragment|  | RTP  |VOP fragment|
 725             |header|header|    (1)     |  |header|    (2)     | ___
 726             +------+------+------------+  +------+------------+
 727
 728              Figure 2 - Examples of RTP packetized MPEG-4 Visual bitstream
 729
 730         So a valid packet should start with
 731         VS      - Visual Object Sequence Header
 732         GOV     - Group_of_VideoObjectPlane
 733         VOP     - Video Object Plane
 734         VP      - Video Plane
 735         Otherwies it's a VOP fragment.
 736
 737         visual_object_sequence_start_code: The visual_object_sequence_start_code is
 738         the bit string '000001B0' in hexadecimal. It initiates a visual session.
 739
 740         group_of_vop_start_code: The group_of_vop_start_code is the bit string '000001B3' in hexadecimal. It identifies
 741         the beginning of a GOV header.
 742
 743         vop_start_code: This is the bit string '000001B6' in hexadecimal.
 744
 745
 746         */
 747                 if (tvb_length(tvb)< 4){
 748                         /* To short to be a start code */
 749                         proto_tree_add_text(tree, tvb, bit_offset>>3, -1, "Data");
 750                         return;
 751                 }
 752                 dword = tvb_get_bits32(tvb,bit_offset, 24, FALSE);
 753                 if (dword != 1){
 754                         /* if it's not 23 zeros followed by 1 it isn't a start code */
 755                         proto_tree_add_text(tree, tvb, bit_offset>>3, -1, "Data");
 756                         return;
 757                 }
 758                 dword = tvb_get_bits8(tvb,24, 8);
 759                 bit_offset = bit_offset+8;
 760                 switch(dword){
 761                 /* vop_start_code */
 762                 case 0xb6:
 763                         proto_tree_add_bits_item(tree, hf_mp4ves_start_code_prefix, tvb, bit_offset, 24, FALSE);
 764                         bit_offset = bit_offset+24;
 765                         /* vop_coding_type 2 bits */
 766                         proto_tree_add_bits_item(tree, hf_mp4ves_vop_coding_type, tvb, bit_offset, 2, FALSE);
 767                         break;
 768                 case 0xb0:
 769                         /* VS start code */
 770                         bit_offset = dissect_mp4ves_VisualObjectSequence(tvb, pinfo, tree, 0);
 771                         break;
 772                 default:
 773                         proto_tree_add_bits_item(tree, hf_mp4ves_start_code_prefix, tvb, bit_offset, 24, FALSE);
 774                         bit_offset = bit_offset+24;
 775                         break;
 776                 }
 777         }
 778
 779 }
 780 /*
 781  * Parameter name profileAndLevel
 782  * Parameter description This is a nonCollapsing GenericParameter
 783  * Parameter identifier value 0
 784  * Parameter status Mandatory
 785  * Parameter type unsignedMax. Shall be in the range 0..255.
 786  * H245:
 787  * unsignedMax       INTEGER(0..65535), -- Look for max
 788  */
 789 static int
 790 dissect_mp4ves_par_profile(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree _U_)
 791 {
 792         int offset = 0;
 793         guint16 lvl;
 794         const gchar *p = NULL;
 795         asn1_ctx_t *actx;
 796
 797         actx = get_asn1_ctx(pinfo->private_data);
 798         DISSECTOR_ASSERT(actx);
 799
 800         lvl = tvb_get_ntohs(tvb, offset);
 801         p = match_strval(lvl, VALS(mp4ves_level_indication_vals));
 802         if (p) {
 803                 proto_item_append_text(actx->created_item, " - profileAndLevel %s", p);
 804         }
 805         offset += 2;
 806         return offset;
 807 }
 808 static int
 809 dissect_mp4ves_par_video_object_type(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree _U_)
 810 {
 811         int offset = 0;
 812         guint16 lvl;
 813         const gchar *p = NULL;
 814         asn1_ctx_t *actx;
 815
 816         actx = get_asn1_ctx(pinfo->private_data);
 817         DISSECTOR_ASSERT(actx);
 818
 819         lvl = tvb_get_ntohs(tvb, offset);
 820         p = match_strval(lvl, VALS(mp4ves_video_object_type_vals));
 821         if (p) {
 822                 proto_item_append_text(actx->created_item, " - video_object_type %s", p);
 823         }
 824         offset += 2;
 825         return offset;
 826 }
 827
 828 static int
 829 dissect_mp4ves_par_decoderConfigurationInformation(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree _U_)
 830 {
 831         asn1_ctx_t *actx;
 832
 833         actx = get_asn1_ctx(pinfo->private_data);
 834         DISSECTOR_ASSERT(actx);
 835
 836         dissect_mp4ves_config(tvb, pinfo, tree);
 837
 838         return tvb_length(tvb);
 839 }
 840
 841 typedef struct _mp4ves_capability_t {
 842         const gchar *id;
 843         const gchar *name;
 844         new_dissector_t content_pdu;
 845 } mp4ves_capability_t;
 846
 847 static mp4ves_capability_t mp4ves_capability_tab[] = {
 848         /* ITU-T H.245  capabilities ISO/IEC 14496-2(m*/
 849         { "GenericCapability/0.0.8.245.1.0.0/nonCollapsing/0", "profileAndLevel", dissect_mp4ves_par_profile },
 850         { "GenericCapability/0.0.8.245.1.0.0/nonCollapsing/1", "object", dissect_mp4ves_par_video_object_type },
 851         { "GenericCapability/0.0.8.245.1.0.0/nonCollapsing/2", "decoderConfigurationInformation", dissect_mp4ves_par_decoderConfigurationInformation },
 852         { "GenericCapability/0.0.8.245.1.0.0/nonCollapsing/3", "drawingOrder", NULL },
 853         { "GenericCapability/0.0.8.245.1.0.0/collapsing/4", "visualBackChannelHandle", NULL },
 854         { NULL, NULL, NULL },
 855 };
 856
 857 static mp4ves_capability_t *find_cap(const gchar *id) {
 858         mp4ves_capability_t *ftr = NULL;
 859         mp4ves_capability_t *f;
 860
 861         for (f=mp4ves_capability_tab; f->id; f++) {
 862                 if (!strcmp(id, f->id)) { ftr = f; break; }
 863         }
 864         return ftr;
 865 }
 866
 867 static void
 868 dissect_mp4ves_name(tvbuff_t *tvb _U_, packet_info *pinfo, proto_tree *tree)
 869 {
 870         asn1_ctx_t *actx;
 871         mp4ves_capability_t *ftr = NULL;
 872
 873         actx = get_asn1_ctx(pinfo->private_data);
 874         DISSECTOR_ASSERT(actx);
 875         if (tree) {
 876                 ftr = find_cap(pinfo->match_string);
 877                 if (ftr) {
 878                         proto_item_append_text(actx->created_item, " - %s", ftr->name);
 879                         proto_item_append_text(proto_item_get_parent(proto_tree_get_parent(tree)), ": %s", ftr->name);
 880                 } else {
 881                         proto_item_append_text(actx->created_item, " - unknown(%s)", pinfo->match_string);
 882                 }
 883         }
 884 }
 885
 886 void
 887 proto_reg_handoff_mp4ves(void);
 888
 889 void
 890 proto_register_mp4ves(void)
 891 {
 892
 893
 894 /* Setup list of header fields  See Section 1.6.1 for details*/
 895         static hf_register_info hf[] = {
 896                 { &hf_mp4ves_config,
 897                   { "Configuration",        "mp4ves.configuration",
 898                     FT_BYTES, BASE_NONE, NULL, 0x0,
 899                     NULL, HFILL }
 900                 },
 901                 { &hf_mp4ves_start_code_prefix,
 902                   { "start code prefix",                "mp4ves.start_code_prefix",
 903                     FT_UINT32, BASE_HEX, NULL, 0x0,
 904                     NULL, HFILL }
 905                 },
 906                 { &hf_mp4ves_start_code,
 907                   { "Start code",               "mp4ves.start_code",
 908                     FT_UINT8, BASE_RANGE_STRING|BASE_HEX, RVALS(&mp4ves_startcode_vals), 0x0,
 909                     NULL, HFILL }
 910                 },
 911                 { &hf_mp4ves_vop_coding_type,
 912                   { "vop_coding_type",          "mp4ves.vop_coding_type",
 913                     FT_UINT8, BASE_DEC, VALS(mp4ves_vop_coding_type_vals), 0x0,
 914                     "Start code", HFILL }
 915                 },
 916                 {&hf_mp4ves_profile_and_level_indication,
 917                  { "profile_and_level_indication",              "mp4ves.profile_and_level_indication",
 918                    FT_UINT8, BASE_DEC,VALS(mp4ves_level_indication_vals), 0x0,
 919                    NULL, HFILL }
 920                 },
 921                 { &hf_mp4ves_is_visual_object_identifier,
 922                   { "visual_object_identifier",         "mp4ves.visual_object_identifier",
 923                     FT_UINT8, BASE_DEC, NULL, 0x0,
 924                     NULL, HFILL }
 925                 },
 926                 { &hf_mp4ves_visual_object_type,
 927                   { "visual_object_type",               "mp4ves.visual_object_type",
 928                     FT_UINT32, BASE_DEC, VALS(mp4ves_visual_object_type_vals), 0x0,
 929                     NULL, HFILL }
 930                 },
 931                 { &hf_mp4ves_video_signal_type,
 932                   { "video_signal_type",                "mp4ves.video_signal_type",
 933                     FT_UINT8, BASE_DEC, NULL, 0x0,
 934                     NULL, HFILL }
 935                 },
 936                 { &hf_mp4ves_stuffing,
 937                   { "Stuffing",         "mp4ves.stuffing",
 938                     FT_UINT8, BASE_DEC, NULL, 0x0,
 939                     NULL, HFILL }
 940                 },
 941                 { &hf_mp4ves_video_object_type_indication,
 942                   { "video_object_type_indication",             "mp4ves.video_object_type_indication",
 943                     FT_UINT8, BASE_DEC, VALS(mp4ves_video_object_type_indication_vals), 0x0,
 944                     NULL, HFILL }
 945                 },
 946                 { &hf_mp4ves_random_accessible_vol,
 947                   { "random_accessible_vol",            "mp4ves.random_accessible_vol",
 948                     FT_UINT8, BASE_DEC, NULL, 0x0,
 949                     "video_object_type_indication", HFILL }
 950                 },
 951                 { &hf_mp4ves_is_object_layer_identifier,
 952                   { "is_object_layer_identifier",               "mp4ves.is_object_layer_identifier",
 953                     FT_UINT8, BASE_DEC, NULL, 0x0,
 954                     NULL, HFILL }
 955                 },
 956                 { &hf_mp4ves_aspect_ratio_info,
 957                   { "aspect_ratio_info",                "mp4ves.aspect_ratio_info",
 958                     FT_UINT8, BASE_DEC, VALS(mp4ves_aspect_ratio_info_vals), 0x0,
 959                     NULL, HFILL }
 960                 },
 961                 { &hf_mp4ves_vol_control_parameters,
 962                   { "vol_control_parameters",           "mp4ves.vol_control_parameters",
 963                     FT_UINT8, BASE_DEC, NULL, 0x0,
 964                     NULL, HFILL }
 965                 },
 966                 { &hf_mp4ves_video_object_layer_shape,
 967                   { "video_object_layer_shape",         "mp4ves.video_object_layer_shape",
 968                     FT_UINT8, BASE_DEC, VALS(mp4ves_video_object_layer_shape_vals), 0x0,
 969                     NULL, HFILL }
 970                 },
 971         };
 972
 973 /* Setup protocol subtree array */
 974         static gint *ett[] = {
 975                 &ett_mp4ves,
 976                 &ett_mp4ves_config,
 977         };
 978
 979         module_t *mp4ves_module;
 980
 981 /* Register the protocol name and description */
 982         proto_mp4ves = proto_register_protocol("MP4V-ES","MP4V-ES", "mp4v-es");
 983
 984 /* Required function calls to register the header fields and subtrees used */
 985         proto_register_field_array(proto_mp4ves, hf, array_length(hf));
 986         proto_register_subtree_array(ett, array_length(ett));
 987         /* Register a configuration option for port */
 988
 989         register_dissector("mp4ves", dissect_mp4ves, proto_mp4ves);
 990
 991         /* Register a configuration option for port */
 992         mp4ves_module = prefs_register_protocol(proto_mp4ves, proto_reg_handoff_mp4ves);
 993
 994         prefs_register_uint_preference(mp4ves_module,
 995                                        "dynamic.payload.type",
 996                                        "MP4V-ES dynamic payload type",
 997                                        "The dynamic payload type which will be interpreted as MP4V-ES",
 998                                        10,
 999                                        &global_dynamic_payload_type);
1000
1001 }
1002
1003 void
1004 proto_reg_handoff_mp4ves(void)
1005 {
1006         static dissector_handle_t mp4ves_handle;
1007         static guint dynamic_payload_type;
1008         static gboolean mp4ves_prefs_initialized = FALSE;
1009
1010         if (!mp4ves_prefs_initialized) {
1011                 dissector_handle_t mp4ves_name_handle;
1012                 mp4ves_capability_t *ftr;
1013
1014                 mp4ves_handle = find_dissector("mp4ves");
1015                 dissector_add_string("rtp_dyn_payload_type","MP4V-ES", mp4ves_handle);
1016                 mp4ves_prefs_initialized = TRUE;
1017
1018                 mp4ves_name_handle = create_dissector_handle(dissect_mp4ves_name, proto_mp4ves);
1019                 for (ftr=mp4ves_capability_tab; ftr->id; ftr++) {
1020                     if (ftr->name)
1021                                 dissector_add_string("h245.gef.name", ftr->id, mp4ves_name_handle);
1022                         if (ftr->content_pdu)
1023                                 dissector_add_string("h245.gef.content", ftr->id, new_create_dissector_handle(ftr->content_pdu, proto_mp4ves));
1024                 }
1025         }else{
1026                 if ( dynamic_payload_type > 95 )
1027                         dissector_delete("rtp.pt", dynamic_payload_type, mp4ves_handle);
1028         }
1029         dynamic_payload_type = global_dynamic_payload_type;
1030
1031         if ( dynamic_payload_type > 95 ){
1032                 dissector_add("rtp.pt", dynamic_payload_type, mp4ves_handle);
1033         }
1034 }
1035