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svn path=/trunk/; revision=21299
This commit is contained in:
Anders Broman 2007-04-02 06:49:28 +00:00
parent 0104002d2e
commit 98cc46f2a4
1 changed files with 139 additions and 7 deletions
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146
epan/dissectors/packet-h263.c
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@ -573,6 +573,8 @@ dissect_h263_picture_layer( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
guint32 source_format;
guint32 ufep;
guint32 picture_coding_type;
guint32 PB_frames_mode = 0;
guint32 cpm;
if(is_rfc4626){
/* PC 1000 00xx */
@ -625,7 +627,7 @@ dissect_h263_picture_layer( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
h263_proto_tree_add_bits( tree, hf_h263_optional_advanced_prediction_mode, tvb, offset_in_bits, 1, NULL);
offset_in_bits++;
/* Bit 13: Optional PB-frames mode (see Annex G), "0" normal I- or P-picture, "1" PB-frame.*/
h263_proto_tree_add_bits( tree, hf_h263_PB_frames_mode, tvb, offset_in_bits, 1, NULL);
h263_proto_tree_add_bits( tree, hf_h263_PB_frames_mode, tvb, offset_in_bits, 1, &PB_frames_mode);
offset_in_bits++;
}else{
/* Extended PTYPE
@ -734,20 +736,150 @@ dissect_h263_picture_layer( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
* (see 5.1.20 and 5.1.21). If PLUSPTYPE is present, then CPM follows
* immediately after PLUSPTYPE in the picture header.
*/
h263_proto_tree_add_bits( tree, hf_h263_cpm, tvb, offset_in_bits, 1, NULL);
h263_proto_tree_add_bits( tree, hf_h263_cpm, tvb, offset_in_bits, 1, &cpm);
offset_in_bits++;
h263_proto_tree_add_bits( tree, hf_h263_psbi, tvb, offset_in_bits, 2, NULL);
offset_in_bits = offset_in_bits +2;
/* 5.1.21 Picture Sub-Bitstream Indicator (PSBI) (2 bits)
* only present if Continuous Presence Multipoint and Video
* Multiplex mode is indicated by CPM.
*/
if(cpm==1){
h263_proto_tree_add_bits( tree, hf_h263_psbi, tvb, offset_in_bits, 2, NULL);
offset_in_bits = offset_in_bits +2;
}
/* TODO Add the rest of the fields */
/* 5.1.5 Custom Picture Format (CPFMT) (23 bits)
* present only if the use of a custom picture format is
* signalled in PLUSPTYPE and UFEP is '001'. When present, CPFMT consists of:
* Bits 1-4 Pixel Aspect Ratio Code: A 4-bit index to the PAR value in Table 5. For
* extended PAR, the exact pixel aspect ratio shall be specified in EPAR
* (see 5.1.6);
* Bits 5-13 Picture Width Indication: Range [0, ... , 511]; Number of pixels per
* line = (PWI + 1) * 4;
* Bit 14 Equal to "1" to prevent start code emulation;
* Bits 15-23 Picture Height Indication: Range [1, ... , 288]; Number of lines = PHI * 4.
*/
/* 5.1.6 Extended Pixel Aspect Ratio (EPAR) (16 bits)
* A fixed length codeword of 16 bits that is present only if CPFMT is present and extended PAR is
* indicated therein. When present, EPAR consists of:
* Bits 1-8 PAR Width: "0" is forbidden. The natural binary representation of the PAR
* width;
* Bits 9-16 PAR Height: "0" is forbidden. The natural binary representation of the PAR
* height.
*/
/* 5.1.7 Custom Picture Clock Frequency Code (CPCFC) (8 bits)
* A fixed length codeword of 8 bits that is present only if PLUSPTYPE is present and UFEP is 001
* and a custom picture clock frequency is signalled in PLUSPTYPE. When present, CPCFC consists of:
* Bit 1 Clock Conversion Code: "0" indicates a clock conversion factor of 1000 and
* "1" indicates 1001;
* Bits 2-8 Clock Divisor: "0" is forbidden. The natural binary representation of the value
* of the clock divisor.
*/
/* 5.1.8 Extended Temporal Reference (ETR) (2 bits)
* A fixed length codeword of 2 bits which is present only if a custom picture clock frequency is in
* use (regardless of the value of UFEP). It is the two MSBs of the 10-bit number defined in 5.1.2.
*/
/* 5.1.9 Unlimited Unrestricted Motion Vectors Indicator (UUI) (Variable length)
* A variable length codeword of 1 or 2 bits that is present only if the optional Unrestricted Motion
* Vector mode is indicated in PLUSPTYPE and UFEP is 001. When UUI is present it indicates the
* effective limitation of the range of the motion vectors being used.
* UUI = "1" The motion vector range is limited according to Tables D.1 and D.2.
* UUI = "01" The motion vector range is not limited except by the picture size.
*/
/*
* 5.1.10 Slice Structured Submode bits (SSS) (2 bits)
* A fixed length codeword of 2 bits which is present only if the optional Slice Structured mode
* (see Annex K) is indicated in PLUSPTYPE and UFEP is 001. If the Slice Structured mode is in use
* but UFEP is not 001, the last values sent for SSS shall remain in effect.
* – Bit 1 Rectangular Slices, "0" indicates free-running slices, "1" indicates rectangular
* slices;
* – Bit 2 Arbitrary Slice Ordering, "0" indicates sequential order, "1" indicates arbitrary
* order.
* 5.1.11 Enhancement Layer Number (ELNUM) (4 bits)
* A fixed length codeword of 4 bits which is present only if the optional Temporal, SNR, and Spatial
* Scalability mode is in use (regardless of the value of UFEP). The particular enhancement layer is
* identified by an enhancement layer number, ELNUM. Picture correspondence between layers is
* achieved via the temporal reference. Picture size is either indicated within each enhancement layer
* using the existing source format fields or is inferred by the relationship to the reference layer. The
* first enhancement layer above the base layer is designated as Enhancement Layer Number 2, and
* the base layer has number 1.
* 5.1.12 Reference Layer Number (RLNUM) (4 bits)
* A fixed length codeword of 4 bits which is present only if the optional Temporal, SNR, and Spatial
* Scalability mode is in use (see Annex O) and UFEP is 001. The layer number for the pictures used
* as reference anchors is identified by a Reference Layer Number (RLNUM). Time correspondence
* between layers is achieved via the temporal reference.
* Note that for B-pictures in an enhancement layer having temporally surrounding EI- or EP-pictures
* which are present in the same enhancement layer, RLNUM shall be equal to ELNUM
* (see Annex O).
* 5.1.13 Reference Picture Selection Mode Flags (RPSMF) (3 bits)
* A fixed length codeword of 3 bits that is present only if the Reference Picture Selection mode is in
* use and UFEP is 001. When present, RPSMF indicates which type of back-channel messages are
* needed by the encoder. If the Reference Picture Selection mode is in use but RPSMF is not present,
* the last value of RPSMF that was sent shall remain in effect.
* – 100: neither ACK nor NACK signals needed;
* – 101: need ACK signals to be returned;
* – 110: need NACK signals to be returned;
* – 111: need both ACK and NACK signals to be returned;
* – 000-011: Reserved.
* 5.1.14 Temporal Reference for Prediction Indication (TRPI) (1 bit)
* A fixed length codeword of 1 bit that is present only if the optional Reference Picture Selection
* mode is in use (regardless of the value of UFEP). When present, TRPI indicates the presence of the
* following TRP field:
* – 0: TRP field is not present;
* – 1: TRP field is present.
* TRPI shall be 0 whenever the picture header indicates an I- or EI-picture.
* 5.1.15 Temporal Reference for Prediction (TRP) (10 bits)
* When present (as indicated in TRPI), TRP indicates the Temporal Reference which is used for
* prediction of the encoding, except for in the case of B-pictures. For B-pictures, the picture having
* the temporal reference TRP is used for the prediction in the forward direction. (Prediction in the
* reverse-temporal direction always uses the immediately temporally subsequent picture.) TRP is a
* ten-bit number. If a custom picture clock frequency was not in use for the reference picture, the two
* MSBs of TRP are zero and the LSBs contain the eight-bit TR found in the picture header of the
* reference picture. If a custom picture clock frequency was in use for the reference picture, TRP is a
* ten-bit number consisting of the concatenation of ETR and TR from the reference picture header.
* When TRP is not present, the most recent temporally previous anchor picture shall be used for
* prediction, as when not in the Reference Picture Selection mode. TRP is valid until the next PSC,
* GSC, or SSC.
* 5.1.16 Back-Channel message Indication (BCI) (Variable length)
* A variable length field of one or two bits that is present only if the optional Reference Picture
* Selection mode is in use. When set to "1", this signals the presence of the following optional video
* Back-Channel Message (BCM) field. "01" indicates the absence or the end of the video backchannel
* message field. Combinations of BCM and BCI may not be present, and may be repeated
* when present. BCI shall be set to "01" if the videomux submode of the optional Reference Picture
* Selection mode is not in use.
* 5.1.17 Back-Channel Message (BCM) (Variable length)
* The Back-Channel message with syntax as specified in N.4.2, which is present only if the preceding
* BCI field is present and is set to "1".
* 5.1.18 Reference Picture Resampling Parameters (RPRP) (Variable length)
* A variable length field that is present only if the optional Reference Picture Resampling mode bit is
* set in PLUSPTYPE. This field carries the parameters of the Reference Picture Resampling mode
* (see Annex P). Note that the Reference Picture Resampling mode can also be invoked implicitly by
* the occurrence of a picture header for an INTER coded picture having a picture size which differs
* from that of the previous encoded picture, in which case the RPRP field is not present and the
* Reference Picture Resampling mode bit is not set.
*/
return offset_in_bits>>3;
}
/* 5.1.19 Quantizer Information (PQUANT) (5 bits) */
h263_proto_tree_add_bits( tree, hf_h263_pquant, tvb, offset_in_bits, 5, NULL);
offset_in_bits = offset_in_bits +5;
if (source_format != H263_PLUSPTYPE){
h263_proto_tree_add_bits( tree, hf_h263_cpm, tvb, offset_in_bits, 1, NULL);
h263_proto_tree_add_bits( tree, hf_h263_cpm, tvb, offset_in_bits, 1, &cpm);
offset_in_bits++;
h263_proto_tree_add_bits( tree, hf_h263_psbi, tvb, offset_in_bits, 2, NULL);
offset_in_bits = offset_in_bits +2;
/* 5.1.21 Picture Sub-Bitstream Indicator (PSBI) (2 bits)
* only present if Continuous Presence Multipoint and Video
* Multiplex mode is indicated by CPM.
*/
if(cpm==1){
h263_proto_tree_add_bits( tree, hf_h263_psbi, tvb, offset_in_bits, 2, NULL);
offset_in_bits = offset_in_bits +2;
}
}
/* 5.1.22 Temporal Reference for B-pictures in PB-frames (TRB) (3/5 bits)
* TRB is present if PTYPE or PLUSPTYPE indicates "PB-frame" or "Improved PB-frame"
* It is 3 bits long for standard CIF picture clock frequency and is
* extended to 5 bits when a custom picture clock frequency is in use.
*/
/* TODO Add the rest of the fields */
return offset_in_bits>>3;