举例分析：
首先是一段例子：
Test.m2v
00 00 01 B3 08 00 80 23 00 FA 20 30 00 00 01 B5
根据13813-2 Table 6-1 Start code values: 00 00 01 B3 为sequence_header_code.根据6.2.2节（附）
horizontal_size_value(12 bits)：08 0 = 128
vertical_size_value(12 bits)：0 80 = 128
aspect_ratio_information(4 bits) = 2
frame_rate_code (4 bits) = 3
bit_rate_value（18 bits） = 00 FA 2>>2 = 0000 0000 1111 1010 00 = 1000
marker_bit(1 bit) = 1
vbv_buffer_size_value(10 bits) = 0 0000 0011 0 = 6
constrained_parameters_flag(1 bit) = 0
load_intra_quantiser_matrix( 1bit) = 0
load_non_intra_quantiser_matrix(1bit) = 0
00 00 01 b5 extension_start_code
14 82 00 01 00 00 00 00 01 B5 23 05 05 05 02 02
04 00 00 00 00 01 B2
extension_start_code_identifier(4 bits) = 1
profile_and_level_indication(8 bit) = 48
progressive_sequence( 1 bit) = 0
chroma_format(2 bits) = 01
horizontal_size_extension(2bit) = 0
vertical_size_extension(2 bit) = 0
bit_rate_extension(12 bit) = 0 0000 0000 000
marker_bit(1 bit) = 1
vbv_buffer_size_extension(8 bits) = 00
low_delay(1 bit) = 0
frame_rate_extension_n(2 bit) = 00
frame_rate_extension_d(5 bit) = 00000
接着，下组是Extension and user data ，00 00 01 B5 extension_start_code，所以接下来是extension_data( i )，
extension_start_code_identifier（4bit） = 2, Sequence Display Extension ID
video_format((3 bit) = 001
colour_description(1bit)=1
colour_primaries(8) = 05
transfer_characteristics(8)=05
matrix_coefficients(8) = 05
display_horizontal_size(14) = 0000 0010 0000 00
marker_bit(1 bit) = 1
display_vertical_size(14) = 0 0000 0100 0000 0
还剩余了3bit 000
接下来是00 00 01 b2 user_data_start_code，user_data()，我们忽略它，因为他是用户自定义的。
00 00 01 B2 4D 50 45 47 2D32 20 56 65 72
69 66 69 63 61 74 69 6F5E20 53 65 71 75 65 6E
63 65 0A 00 00 01 B8
00 00 01 B8 ，group_start_code, group_of_pictures_header
00 00 01 B8 5FBF 6C 40
time_code(25): 0101 1111 1011 1111 0110 1100 0 = 49022
closed_gop(1): 1
broken_link(1):0
剩余5bit 0 0000
00 00 01 00 00
0A 58 58 00 00 01 B5
00 00 01 00, picture_start_code, picture_header
temporal_reference(10): 0000 0000 00
picture_coding_type(3): 00 1
vbv_delay(16):001 1000 1001 1
extra_bit_picture(1):0
00 00 01 B5 8F FF F7 CC 00 00 00 01 01
00 00 01 B5: extension_start_code，所以接下来是extension_data( i )，
extension_start_code_identifier（4bit） = 8, Picture Coding Extension ID,6.2.3.1节
f_code[0][0] /* forward horizontal */(4): F
f_code[0][1] /* forward vertical */(4):F
f_code[1][0] /* backward horizontal */(4):F
f_code[1][1] /* backward vertical */(4):F
intra_dc_precision(2): 01
picture_structure(2): 11
top_field_first(1):1
frame_pred_frame_dct(1):1
concealment_motion_vectors(1):0
q_scale_type(1):0
intra_vlc_format:(1):1
alternate_scan(1);1
repeat_first_field(1):0
chroma_420_type(1):0
progressive_frame(1);0
composite_display_flag(1):0
所以接下来将是picture_data,即是很多slice
00 00 01 01: slice_start_code，
Sequence header中horizontal_size_value 和Sequence header extention中的horizontal_size 组成了horizontal_size。
53 D0 54 90 F1 E7 21 48 18 A0 3C24 B6 F3 4A D2
quantiser_scale_code(5): 0101 0 = 10
extra_bit_slice /* with the value “0” */ (1):0
接下来就是macroblock()了。
macroblock_address_increment(1-11) — This is a variable length coded integer coded as per Annex B Table B-1,
查表得：macroblock_address_increment = 1
macroblock_modes()：table 6.2.51.
macroblock_type(1-9): Tables B-2 through B-8, selected by picture_coding_type and scalable_mode.
1 1101 0000
查表得：macroblock_type = 1,I picture,no scale
macroblock_quant = 0
macroblock_motion_forward = 0
macroblock_motion_backward = 0
macroblock_pattern = 0
macroblock_intra = 1
spatial_temporal_weight_code_flag = 0
permitted spatial_temporal_weight_classes:0 ,Intra
所以没有其他结构，block_count = Table 6-20(并根据chroma_format’10’ = ‘4:2:0‘ see Table 6-5 8-5) 全是block = 6。
VLC见7.2节：
对于前4个blcok，cc = 0.cc = 0，使用B-12,cc!=0,使用B13
First DCT coefficient(3-24)即是DC系数，根据B-12,B13.
First DCT coefficient = 110, dct_dc_size_luminance = 4,所以dct_dc_differential(=4bit)
dct_dc_differential = 1 000
pattern_code[i] = 1 默认?
First DCT coefficient应该 = 预测值+differential，预测值初始化0,然后[i]的预测值变为1000 = 8, intra_dc_precision((picture_coding_extension) = 01, 所以Precision (bits) = 9， 由7.4.1得
First DCT coefficient = 8*4 = 32。
然后是接下来的AC系数。
53 D0 54 90 F1 E7 21
48 18 A0 3C 24
B6 F3 4A D2
0 0101 0100 1001 0000 1111 0001 1110 0111 0010 0001
0100 1000 0001 0100 1010 0000 0011 1100 0010 0100
1011 0110 1111 0011 0100 1010 1101 0010
根据b-14,B-15得：
AC：intra_vlc_format (picture_coding_extension) = 1,macroblock_intra = 1,所以使用B-15
quantiser_scale_code (slice header)= 10, q_scale_type(picture_coding_extension) = 0, quantiser_scale[q_scale_type] = 20.根据7.4.2.3 intra_block,加权系数根据6.2.3.2决定,或6.3.11有个默认矩阵。矩阵z字型对应alternate_scan(picturecodeing_extension)决定。
val = val * quantiser_scale[q_scale_type] * w[]/16;
00101: run 2 level 1 len5,run代表0的个数。,AC[1] = 0,AC[2] = 0
0：signed,所以AC[3] = 1 计算= 1* 20* 22/16 = 27
10:run 0 level 1 len 2,
0:signed,AC[4]=1 计算 =1*20*16/16 = 20
0 1001
。。。。。。。
最后得到一个block:
32 20 23 27 32 -33 0 0
0 20 0 0 0 0 0 0
0 0 0 0 36 0 0 0
27 0 0 33 0 0 0 0
-27 0 0 0 0 0 0 0
0 -33 36 0 87 0 -60 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
根据alter的z-zig的排列，dc = 32, ac[1] = 0,ac[2] = 0,ac[3] = 27,ac[4] = 20,……图II2-7.3
然后经过IDCT:
38 4 -35 7 28 -15 -9 18
…….
然后把所有变成一个范围内的Clip.
把所有的block到结束时，就行成了一个完整的Frame.
附录，主要
Table 6-1 — Start code values
|
Name
|
start code value
(hexadecimal)
|
|
picture_start_code
|
00
|
|
Slice_start_code
|
01 through AF
|
|
Reserved
|
B0
|
|
Reserved
|
B1
|
|
User_data_start_code
|
B2
|
|
sequence_header_code
|
B3
|
|
sequence_error_code
|
B4
|
|
extension_start_code
|
B5
|
|
Reserved
|
B6
|
|
Sequence_end_code
|
B7
|
|
group_start_code
|
B8
|
|
system start codes (see note)
|
B9 through FF
|
|
NOTE - system start codes are defined in Part 1 of this specification
|
6.2.2节：
|
video_sequence() {
|
|
next_start_code()
|
|
sequence_header()
|
|
if ( nextbits() == extension_start_code ) {
|
|
sequence_extension()
|
|
do {
|
|
extension_and_user_data( 0 )
|
|
do {
|
|
if (nextbits() == group_start_code) {
|
|
group_of_pictures_header()
|
|
Extension_and_user_data( 1 )
|
|
}
|
|
picture_header()
|
|
picture_coding_extension()
|
|
extensions_and_user_data( 2 )
|
|
picture_data()
|
|
} while ( (nextbits() == picture_start_code) ||
|
|
(nextbits() == group_start_code) )
|
|
if ( nextbits() != sequence_end_code ) {
|
|
sequence_header()
|
|
sequence_extension()
|
|
}
|
|
} while ( nextbits() != sequence_end_code )
|
|
} else {
|
|
/* ISO/IEC 11172-2 */
|
|
}
|
|
sequence_end_code
|
|
}
|
|
|
6.2.2.1 Sequence header
|
sequence_header() {
|
No. of bits
|
Mnemonic
|
|
sequence_header_code
|
32
|
bslbf
|
|
horizontal_size_value
|
12
|
uimsbf
|
|
vertical_size_value
|
12
|
uimsbf
|
|
aspect_ratio_information
|
4
|
uimsbf
|
|
frame_rate_code
|
4
|
uimsbf
|
|
bit_rate_value
|
18
|
uimsbf
|
|
marker_bit
|
1
|
bslbf
|
|
vbv_buffer_size_value
|
10
|
uimsbf
|
|
constrained_parameters_flag
|
1
|
|
|
load_intra_quantiser_matrix
|
1
|
|
|
if ( load_intra_quantiser_matrix )
|
|
|
|
intra_quantiser_matrix[64]
|
8*64
|
uimsbf
|
|
load_non_intra_quantiser_matrix
|
1
|
|
|
if ( load_non_intra_quantiser_matrix )
|
|
|
|
non_intra_quantiser_matrix[64]
|
8*64
|
uimsbf
|
|
next_start_code()
|
|
|
|
}
|
|
|
6.2.2.3 Sequence extension
|
sequence_extension() {
|
No. of bits
|
Mnemonic
|
|
extension_start_code
|
32
|
bslbf
|
|
extension_start_code_identifier
|
4
|
uimsbf
|
|
profile_and_level_indication
|
8
|
uimsbf
|
|
progressive_sequence
|
1
|
uimsbf
|
|
chroma_format
|
2
|
uimsbf
|
|
horizontal_size_extension
|
2
|
uimsbf
|
|
vertical_size_extension
|
2
|
uimsbf
|
|
bit_rate_extension
|
12
|
uimsbf
|
|
marker_bit
|
1
|
bslbf
|
|
vbv_buffer_size_extension
|
8
|
uimsbf
|
|
low_delay
|
1
|
uimsbf
|
|
frame_rate_extension_n
|
2
|
uimsbf
|
|
frame_rate_extension_d
|
5
|
uimsbf
|
|
next_start_code()
|
|
|
|
}
|
|
|
6.2.2.2 Extension and user data
|
extension_and_user_data( i ) {
|
No. of bits
|
Mnemonic
|
|
while ( ( ( i != 1) && ( nextbits()== extension_start_code ) ) ||
|
|
|
|
( nextbits()== user_data_start_code ) ) {
|
|
|
|
if ( nextbits()== extension_start_code )
|
|
|
|
extension_data( i )
|
|
|
|
if ( nextbits()== user_data_start_code )
|
|
|
|
user_data()
|
|
|
|
}
|
|
|
|
}
|
|
|
Table 6-2. extension_start_code_identifier codes.
|
extension_start_code_identifier
|
Name
|
|
0000
|
reserved
|
|
0001
|
Sequence Extension ID
|
|
0010
|
Sequence Display Extension ID
|
|
0011
|
Quant Matrix Extension ID
|
|
0100
|
Copyright Extension ID
|
|
0101
|
Sequence Scalable Extension ID
|
|
0110
|
reserved
|
|
0111
|
Picture Display Extension ID
|
|
1000
|
Picture Coding Extension ID
|
|
1001
|
Picture Spatial Scalable Extension ID
|
|
1010
|
Picture Temporal Scalable Extension ID
|
|
1011
|
reserved
|
|
1100
|
reserved
|
|
...
|
...
|
|
1111
|
reserved
|
6.2.2.4 Sequence display extension
|
sequence_display_extension() {
|
No. of bits
|
Mnemonic
|
|
extension_start_code_identifier
|
4
|
uimsbf
|
|
video_format
|
3
|
uimsbf
|
|
colour_description
|
1
|
uimsbf
|
|
if ( colour_description ) {
|
|
|
|
colour_primaries
|
8
|
uimsbf
|
|
transfer_characteristics
|
8
|
uimsbf
|
|
matrix_coefficients
|
8
|
uimsbf
|
|
}
|
|
|
|
display_horizontal_size
|
14
|
uimsbf
|
|
marker_bit
|
1
|
bslbf
|
|
display_vertical_size
|
14
|
uimsbf
|
|
next_start_code()
|
|
|
|
}
|
|
|
6.2.2.2.2 User data
|
user_data() {
|
No. of bits
|
Mnemonic
|
|
user_data_start_code
|
32
|
bslbf
|
|
while( nextbits() != ‘0000 0000 0000 0000 0000 0001’ ) {
|
|
|
|
user_data
|
8
|
|
|
}
|
|
|
|
next_start_code()
|
|
|
|
}
|
|
|
6.2.2.6 Group of pictures header
|
group_of_pictures_header() {
|
No. of bits
|
Mnemonic
|
|
group_start_code
|
32
|
bslbf
|
|
time_code
|
25
|
bslbf
|
|
closed_gop
|
1
|
uimsbf
|
|
broken_link
|
1
|
uimsbf
|
|
next_start_code()
|
|
|
|
}
|
|
|
6.2.3 Picture header
|
picture_header() {
|
No. of bits
|
Mnemonic
|
|
picture_start_code
|
32
|
bslbf
|
|
temporal_reference
|
10
|
uimsbf
|
|
picture_coding_type
|
3
|
uimsbf
|
|
vbv_delay
|
16
|
uimsbf
|
|
if ( picture_coding_type == 2 || picture_coding_type == 3) {
|
|
|
|
full_pel_forward_vector
|
1
|
|
|
forward_f_code
|
3
|
uimsbf
|
|
}
|
|
|
|
if ( picture_coding_type == 3 ) {
|
|
|
|
full_pel_backward_vector
|
1
|
|
|
backward_f_code
|
3
|
uimsbf
|
|
}
|
|
|
|
while ( nextbits() == '1' ) {
|
|
|
|
extra_bit_picture /* with the value “1” */
|
1
|
uimsbf
|
|
extra_information_picture
|
8
|
|
|
}
|
|
|
|
extra_bit_picture /* with the value “0” */
|
1
|
uimsbf
|
|
next_start_code()
|
|
|
|
}
|
|
|
6.2.3.1 Picture coding extension
|
picture_coding_extension() {
|
No . of bits
|
Mnemonic
|
|
extension_start_code
|
32
|
bslbf
|
|
extension_start_code_identifier
|
4
|
uimsbf
|
|
f_code[0][0] /* forward horizontal */
|
4
|
uimsbf
|
|
f_code[0][1] /* forward vertical */
|
4
|
uimsbf
|
|
f_code[1][0] /* backward horizontal */
|
4
|
uimsbf
|
|
f_code[1][1] /* backward vertical */
|
4
|
uimsbf
|
|
intra_dc_precision
|
2
|
uimsbf
|
|
picture_structure
|
2
|
uimsbf
|
|
top_field_first
|
1
|
uimsbf
|
|
frame_pred_frame_dct
|
1
|
uimsbf
|
|
concealment_motion_vectors
|
1
|
uimsbf
|
|
q_scale_type
|
1
|
uimsbf
|
|
intra_vlc_format
|
1
|
uimsbf
|
|
alternate_scan
|
1
|
uimsbf
|
|
repeat_first_field
|
1
|
uimsbf
|
|
chroma_420_type
|
1
|
uimsbf
|
|
progressive_frame
|
1
|
uimsbf
|
|
composite_display_flag
|
1
|
uimsbf
|
|
if ( composite_display_flag ) {
|
|
|
|
v_axis
|
1
|
uimsbf
|
|
field_sequence
|
3
|
uimsbf
|
|
sub_carrier
|
1
|
uimsbf
|
|
burst_amplitude
|
7
|
uimsbf
|
|
sub_carrier_phase
|
8
|
uimsbf
|
|
}
|
|
|
|
next_start_code()
|
|
|
|
}
|
|
|
6.2.3.6 Picture data
|
picture_data() {
|
No. of bits
|
Mnemonic
|
|
do {
|
|
|
|
slice()
|
|
|
|
} while ( nextbits() == slice_start_code )
|
|
|
|
next_start_code()
|
|
|
|
}
|
|
|
6.2.4 Slice
|
slice() {
|
No. of bits
|
Mnemonic
|
|
slice_start_code
|
32
|
bslbf
|
|
if (vertical_size > 2800)
|
|
|
|
slice_vertical_position_extension
|
3
|
uimsbf
|
|
if ( <sequence_scalable_extension() is present in the bitstream> )
|
|
|
|
if (scalable_mode == “data partitioning” )
|
|
|
|
priority_breakpoint
|
7
|
uimsbf
|
|
quantiser_scale_code
|
5
|
uimsbf
|
|
if ( nextbits() == '1' ) {
|
|
|
|
intra_slice_flag
|
1
|
bslbf
|
|
intra_slice
|
1
|
uimsbf
|
|
reserved_bits
|
7
|
uimsbf
|
|
while ( nextbits() == '1' ) {
|
|
|
|
extra_bit_slice /* with the value “1” */
|
1
|
uimsbf
|
|
extra_information_slice
|
8
|
|
|
}
|
|
|
|
}
|
|
|
|
extra_bit_slice /* with the value “0” */
|
1
|
Uimsbf
|
|
do {
|
|
|
|
macroblock()
|
|
|
|
} while ( nextbits() != '000 0000 0000 0000 0000 0000' )
|
|
|
|
next_start_code()
|
|
|
|
}
|
|
|
B.1 Macroblock addressing
Table B-1 --- Variable length codes for macroblock_address_increment
|
macroblock_address_ increment VLC code
|
increment value
|
macroblock_address_ increment VLC code
|
increment value
|
|
1
|
1
|
0000 0101 01
|
18
|
|
011
|
2
|
0000 0101 00
|
19
|
|
010
|
3
|
0000 0100 11
|
20
|
|
0011
|
4
|
0000 0100 10
|
21
|
|
0010
|
5
|
0000 0100 011
|
22
|
|
0001 1
|
6
|
0000 0100 010
|
23
|
|
0001 0
|
7
|
0000 0100 001
|
24
|
|
0000 111
|
8
|
0000 0100 000
|
25
|
|
0000 110
|
9
|
0000 0011 111
|
26
|
|
0000 1011
|
10
|
0000 0011 110
|
27
|
|
0000 1010
|
11
|
0000 0011 101
|
28
|
|
0000 1001
|
12
|
0000 0011 100
|
29
|
|
0000 1000
|
13
|
0000 0011 011
|
30
|
|
0000 0111
|
14
|
0000 0011 010
|
31
|
|
0000 0110
|
15
|
0000 0011 001
|
32
|
|
0000 0101 11
|
16
|
0000 0011 000
|
33
|
|
0000 0101 10
|
17
|
0000 0001 000
|
macroblock_escape
|
Note: The “macroblock stuffing” entry that is available in ISO/IEC11172-2 is not available in this specification.
B.2 Macroblock type
The properties of the macroblock are determined by the macroblock type VLC according to these tables.
Table B-2 — Variable length codes for macroblock_type in I-pictures
|
macroblock_type VLC code
|
|
|
macroblock_quant
|
|
|
|
macroblock_motion_forward
|
|
|
|
|
macroblock_motion_backward
|
|
|
|
|
|
macroblock_pattern
|
|
|
|
|
|
|
macroblock_intra
|
|
|
|
|
|
|
|
spatial_temporal_weight_code_flag
|
|
|
|
|
|
|
|
|
permitted spatial_temporal_weight_classes
|
|
|
|
|
|
|
|
|
Description
|
|
|
1
|
0
|
0
|
0
|
0
|
1
|
0
|
Intra
|
0
|
|
01
|
1
|
0
|
0
|
0
|
1
|
0
|
Intra, Quant
|
0
|
Table B-3 — Variable length codes for macroblock_type in P-pictures
|
macroblock_type VLC code
|
|
|
macroblock_quant
|
|
|
|
macroblock_motion_forward
|
|
|
|
|
macroblock_motion_backward
|
|
|
|
|
|
macroblock_pattern
|
|
|
|
|
|
|
macroblock_intra
|
|
|
|
|
|
|
|
spatial_temporal_weight_code_flag
|
|
|
|
|
|
|
|
|
permitted spatial_temporal_weight_classes
|
|
|
|
|
|
|
|
|
Description
|
|
|
1
|
0
|
1
|
0
|
1
|
0
|
0
|
MC, Coded
|
0
|
|
01
|
0
|
0
|
0
|
1
|
0
|
0
|
No MC, Coded
|
0
|
|
001
|
0
|
1
|
0
|
0
|
0
|
0
|
MC, Not Coded
|
0
|
|
0001 1
|
0
|
0
|
0
|
0
|
1
|
0
|
Intra
|
0
|
|
0001 0
|
1
|
1
|
0
|
1
|
0
|
0
|
MC, Coded, Quant
|
0
|
|
0000 1
|
1
|
0
|
0
|
1
|
0
|
0
|
No MC, Coded, Quant
|
0
|
|
0000 01
|
1
|
0
|
0
|
0
|
1
|
0
|
Intra, Quant
|
0
|
Table B-4 — Variable length codes for macroblock_type in B-pictures
|
macroblock_type VLC code
|
|
|
macroblock_quant
|
|
|
|
macroblock_motion_forward
|
|
|
|
|
macroblock_motion_backward
|
|
|
|
|
|
macroblock_pattern
|
|
|
|
|
|
|
macroblock_intra
|
|
|
|
|
|
|
|
spatial_temporal_weight_code_flag
|
|
|
|
|
|
|
|
|
permitted spatial_temporal_weight_classes
|
|
|
|
|
|
|
|
|
Description
|
|
|
10
|
0
|
1
|
1
|
0
|
0
|
0
|
Interp, Not Coded
|
0
|
|
11
|
0
|
1
|
1
|
1
|
0
|
0
|
Interp, Coded
|
0
|
|
010
|
0
|
0
|
1
|
0
|
0
|
0
|
Bwd, Not Coded
|
0
|
|
011
|
0
|
0
|
1
|
1
|
0
|
0
|
Bwd, Coded
|
0
|
|
0010
|
0
|
1
|
0
|
0
|
0
|
0
|
Fwd, Not Coded
|
0
|
|
0011
|
0
|
1
|
0
|
1
|
0
|
0
|
Fwd, Coded
|
0
|
|
0001 1
|
0
|
0
|
0
|
0
|
1
|
0
|
Intra
|
0
|
|
0001 0
|
1
|
1
|
1
|
1
|
0
|
0
|
Interp, Coded, Quant
|
0
|
|
0000 11
|
1
|
1
|
0
|
1
|
0
|
0
|
Fwd, Coded, Quant
|
0
|
|
0000 10
|
1
|
0
|
1
|
1
|
0
|
0
|
Bwd, Coded, Quant
|
0
|
|
0000 01
|
1
|
0
|
0
|
0
|
1
|
0
|
Intra, Quant
|
0
|
Table B-5 — Variable length codes for macroblock_type in I-pictures with spatial scalability.
|
macroblock_type VLC code
|
|
|
macroblock_quant
|
|
|
|
macroblock_motion_forward
|
|
|
|
|
macroblock_motion_backward
|
|
|
|
|
|
macroblock_pattern
|
|
|
|
|
|
|
macroblock_intra
|
|
|
|
|
|
|
|
spatial_temporal_weight_code_flag
|
|
|
|
|
|
|
|
|
permitted spatial_temporal_weight_classes
|
|
|
|
|
|
|
|
|
Description
|
|
|
1
|
0
|
0
|
0
|
1
|
0
|
0
|
Coded, Compatible
|
4
|
|
01
|
1
|
0
|
0
|
1
|
0
|
0
|
Coded, Compatible, Quant
|
4
|
|
0011
|
0
|
0
|
0
|
0
|
1
|
0
|
Intra
|
0
|
|
0010
|
1
|
0
|
0
|
0
|
1
|
0
|
Intra, Quant
|
0
|
|
0001
|
0
|
0
|
0
|
0
|
0
|
0
|
Not Coded, Compatible
|
4
|
Table B-6 — Variable length codes for macroblock_type in P-pictures with spatial scalability.
|
macroblock_type VLC code
|
|
|
macroblock_quant
|
|
|
|
macroblock_motion_forward
|
|
|
|
|
macroblock_motion_backward
|
|
|
|
|
|
macroblock_pattern
|
|
|
|
|
|
|
macroblock_intra
|
|
|
|
|
|
|
|
spatial_temporal_weight_code_flag
|
|
|
|
|
|
|
|
|
permitted spatial_temporal_weight_classes
|
|
|
|
|
|
|
|
|
Description
|
|
|
10
|
0
|
1
|
0
|
1
|
0
|
0
|
MC, Coded
|
0
|
|
011
|
0
|
1
|
0
|
1
|
0
|
1
|
MC, Coded, Compatible
|
1,2,3
|
|
0000 100
|
0
|
0
|
0
|
1
|
0
|
0
|
No MC, Coded
|
0
|
|
0001 11
|
0
|
0
|
0
|
1
|
0
|
1
|
No MC, Coded, Compatible
|
1,2,3
|
|
0010
|
0
|
1
|
0
|
0
|
0
|
0
|
MC, Not Coded
|
0
|
|
0000 111
|
0
|
0
|
0
|
0
|
1
|
0
|
Intra
|
0
|
|
0011
|
0
|
1
|
0
|
0
|
0
|
1
|
MC, Not coded, Compatible
|
1,2,3
|
|
010
|
1
|
1
|
0
|
1
|
0
|
0
|
MC, Coded, Quant
|
0
|
|
0001 00
|
1
|
0
|
0
|
1
|
0
|
0
|
No MC, Coded, Quant
|
0
|
|
0000 110
|
1
|
0
|
0
|
0
|
1
|
0
|
Intra, Quant
|
0
|
|
11
|
1
|
1
|
0
|
1
|
0
|
1
|
MC, Coded, Compatible, Quant
|
1,2,3
|
|
0001 01
|
1
|
0
|
0
|
1
|
0
|
1
|
No MC, Coded, Compatible, Quant
|
1,2,3
|
|
0001 10
|
0
|
0
|
0
|
0
|
0
|
1
|
No MC, Not Coded, Compatible
|
1,2,3
|
|
0000 101
|
0
|
0
|
0
|
1
|
0
|
0
|
Coded, Compatible
|
4
|
|
0000 010
|
1
|
0
|
0
|
1
|
0
|
0
|
Coded, Compatible, Quant
|
4
|
|
0000 011
|
0
|
0
|
0
|
0
|
0
|
0
|
Not Coded, Compatible
|
4
|
Table B-7 — Variable length codes for macroblock_type in B-pictures with spatial scalability.
|
macroblock_type VLC code
|
|
|
macroblock_quant
|
|
|
|
macroblock_motion_forward
|
|
|
|
|
macroblock_motion_backward
|
|
|
|
|
|
macroblock_pattern
|
|
|
|
|
|
|
macroblock_intra
|
|
|
|
|
|
|
|
spatial_temporal_weight_code_flag
|
|
|
|
|
|
|
|
|
permitted spatial_temporal_weight_classes
|
|
|
|
|
|
|
|
|
Description
|
|
|
10
|
0
|
1
|
1
|
0
|
0
|
0
|
Interp, Not coded
|
0
|
|
11
|
0
|
1
|
1
|
1
|
0
|
0
|
Interp, Coded
|
0
|
|
010
|
0
|
0
|
1
|
0
|
0
|
0
|
Back, Not coded
|
0
|
|
011
|
0
|
0
|
1
|
1
|
0
|
0
|
Back, Coded
|
0
|
|
0010
|
0
|
1
|
0
|
0
|
0
|
0
|
For, Not coded
|
0
|
|
0011
|
0
|
1
|
0
|
1
|
0
|
0
|
For, Coded
|
0
|
|
0001 10
|
0
|
0
|
1
|
0
|
0
|
1
|
Back, Not Coded, Compatible
|
1,2,3
|
|
0001 11
|
0
|
0
|
1
|
1
|
0
|
1
|
Back, Coded, Compatible
|
1,2,3
|
|
0001 00
|
0
|
1
|
0
|
0
|
0
|
1
|
For, Not Coded, Compatible
|
1,2,3
|
|
0001 01
|
0
|
1
|
0
|
1
|
0
|
1
|
For, Coded, Compatible
|
1,2,3
|
|
0000 110
|
0
|
0
|
0
|
0
|
1
|
0
|
Intra
|
0
|
|
0000 111
|
1
|
1
|
1
|
1
|
0
|
0
|
Interp, Coded, Quant
|
0
|
|
0000 100
|
1
|
1
|
0
|
1
|
0
|
0
|
For, Coded, Quant
|
0
|
|
0000 101
|
1
|
0
|
1
|
1
|
0
|
0
|
Back, Coded, Quant
|
0
|
|
0000 0100
|
1
|
0
|
0
|
0
|
1
|
0
|
Intra, Quant
|
0
|
|
0000 0101
|
1
|
1
|
0
|
1
|
0
|
1
|
For, Coded, Compatible, Quant
|
1,2,3
|
|
0000 0110 0
|
1
|
0
|
1
|
1
|
0
|
1
|
Back, Coded, Compatible, Quant
|
1,2,3
|
|
0000 0111 0
|
0
|
0
|
0
|
0
|
0
|
0
|
Not Coded, Compatible
|
4
|
|
0000 0110 1
|
1
|
0
|
0
|
1
|
0
|
0
|
Coded, Compatible, Quant
|
4
|
|
0000 0111 1
|
0
|
0
|
0
|
1
|
0
|
0
|
Coded, Compatible
|
4
|
Table B-8 — Variable length codes for macroblock_type in I-pictures, P-pictures and B-pictures with SNR scalability.
|
macroblock_type VLC code
|
|
|
macroblock_quant
|
|
|
|
macroblock_motion_forward
|
|
|
|
|
macroblock_motion_backward
|
|
|
|
|
|
macroblock_pattern
|
|
|
|
|
|
|
macroblock_intra
|
|
|
|
|
|
|
|
spatial_temporal_weight_code_flag
|
|
|
|
|
|
|
|
|
permitted spatial_temporal_weight_classes
|
|
|
|
|
|
|
|
|
Description
|
|
|
1
|
0
|
0
|
0
|
1
|
0
|
0
|
Coded
|
0
|
|
01
|
1
|
0
|
0
|
1
|
0
|
0
|
Coded, Quant
|
0
|
|
001
|
0
|
0
|
0
|
0
|
0
|
0
|
Not Coded
|
0
|
Note There is no differentiation between picture types, since macroblocks are processed identically in I, P and B-pictures. The "Not coded" type is needed, since skipped macroblocks are not allowed at beginning and end of a slice.
B.3 Macroblock pattern
Table B-9 --- Variable length codes for coded_block_pattern.
|
coded_block_pattern VLC code
|
cbp
|
coded_block_pattern VLC code
|
cbp
|
|
111
|
60
|
0001 1100
|
35
|
|
1101
|
4
|
0001 1011
|
13
|
|
1100
|
8
|
0001 1010
|
49
|
|
1011
|
16
|
0001 1001
|
21
|
|
1010
|
32
|
0001 1000
|
41
|
|
1001 1
|
12
|
0001 0111
|
14
|
|
1001 0
|
48
|
0001 0110
|
50
|
|
1000 1
|
20
|
0001 0101
|
22
|
|
1000 0
|
40
|
0001 0100
|
42
|
|
0111 1
|
28
|
0001 0011
|
15
|
|
0111 0
|
44
|
0001 0010
|
51
|
|
0110 1
|
52
|
0001 0001
|
23
|
|
0110 0
|
56
|
0001 0000
|
43
|
|
0101 1
|
1
|
0000 1111
|
25
|
|
0101 0
|
61
|
0000 1110
|
37
|
|
0100 1
|
2
|
0000 1101
|
26
|
|
0100 0
|
62
|
0000 1100
|
38
|
|
0011 11
|
24
|
0000 1011
|
29
|
|
0011 10
|
36
|
0000 1010
|
45
|
|
0011 01
|
3
|
0000 1001
|
53
|
|
0011 00
|
63
|
0000 1000
|
57
|
|
0010 111
|
5
|
0000 0111
|
30
|
|
0010 110
|
9
|
0000 0110
|
46
|
|
0010 101
|
17
|
0000 0101
|
54
|
|
0010 100
|
33
|
0000 0100
|
58
|
|
0010 011
|
6
|
0000 0011 1
|
31
|
|
0010 010
|
10
|
0000 0011 0
|
47
|
|
0010 001
|
18
|
0000 0010 1
|
55
|
|
0010 000
|
34
|
0000 0010 0
|
59
|
|
0001 1111
|
7
|
0000 0001 1
|
27
|
|
0001 1110
|
11
|
0000 0001 0
|
39
|
|
0001 1101
|
19
|
0000 0000 1
|
0 (NOTE)
|
|
NOTE — This entry shall not be used with 4:2:0 chrominance structure
|
6.2.5.1 Macroblock modes
|
macroblock_modes() {
|
No. of bits
|
Mnemonic
|
|
macroblock_type
|
1-9
|
vlclbf
|
|
if ( ( spatial_temporal_weight_code_flag == 1 ) &&
|
|
|
|
( spatial_temporal_weight_code_table_index != ‘00’) ) {
|
|
|
|
spatial_temporal_weight_code
|
2
|
uimsbf
|
|
}
|
|
|
|
if ( macroblock_motion_forward ||
|
|
|
|
macroblock_motion_backward ) {
|
|
|
|
if ( picture_structure == ‘frame’ ) {
|
|
|
|
if ( frame_pred_frame_dct == 0 )
|
|
|
|
frame_motion_type
|
2
|
uimsbf
|
|
} else {
|
|
|
|
field_motion_type
|
2
|
uimsbf
|
|
}
|
|
|
|
}
|
|
|
|
if ( ( picture_structure == “Frame picture” ) &&
|
|
|
|
( frame_pred_frame_dct == 0 ) &&
|
|
|
|
( macroblock_intra || macoblock_pattern) ){
|
|
|
|
dct_type
|
1
|
uimsbf
|
|
}
|
|
|
|
}
|
|
|
|
block( i ) {
|
No. of bits
|
Mnemonic
|
|
if ( pattern_code[i] ) {
|
|
|
|
if ( macroblock_intra ) {
|
|
|
|
if ( i<4 ) {
|
|
|
|
dct_dc_size_luminance
|
2-9
|
vlclbf
|
|
if(dct_dc_size_luminance != 0)
|
|
|
|
dct_dc_differential
|
1-11
|
uimsbf
|
|
} else {
|
|
|
|
dct_dc_size_chrominance
|
2-10
|
vlclbf
|
|
if(dct_dc_size_chrominance !=0)
|
|
|
|
dct_dc_differential
|
1-11
|
uimsbf
|
|
}
|
|
|
|
} else {
|
|
|
|
First DCT coefficient
|
3-24
|
|
|
}
|
|
|
|
while ( nextbits() != End of block )
|
|
|
|
Subsequent DCT coefficients
|
2-24
|
|
|
End of block
|
2 or 4
|
vlclbf
|
|
}
|
|
|
|
}
|
|
|
B.3 Macroblock pattern
Table B-9 --- Variable length codes for coded_block_pattern.
|
coded_block_pattern VLC code
|
cbp
|
coded_block_pattern VLC code
|
cbp
|
|
111
|
60
|
0001 1100
|
35
|
|
1101
|
4
|
0001 1011
|
13
|
|
1100
|
8
|
0001 1010
|
49
|
|
1011
|
16
|
0001 1001
|
21
|
|
1010
|
32
|
0001 1000
|
41
|
|
1001 1
|
12
|
0001 0111
|
14
|
|
1001 0
|
48
|
0001 0110
|
50
|
|
1000 1
|
20
|
0001 0101
|
22
|
|
1000 0
|
40
|
0001 0100
|
42
|
|
0111 1
|
28
|
0001 0011
|
15
|
|
0111 0
|
44
|
0001 0010
|
51
|
|
0110 1
|
52
|
0001 0001
|
23
|
|
0110 0
|
56
|
0001 0000
|
43
|
|
0101 1
|
1
|
0000 1111
|
25
|
|
0101 0
|
61
|
0000 1110
|
37
|
|
0100 1
|
2
|
0000 1101
|
26
|
|
0100 0
|
62
|
0000 1100
|
38
|
|
0011 11
|
24
|
0000 1011
|
29
|
|
0011 10
|
36
|
0000 1010
|
45
|
|
0011 01
|
3
|
0000 1001
|
53
|
|
0011 00
|
63
|
0000 1000
|
57
|
|
0010 111
|
5
|
0000 0111
|
30
|
|
0010 110
|
9
|
0000 0110
|
46
|
|
0010 101
|
17
|
0000 0101
|
54
|
|
0010 100
|
33
|
0000 0100
|
58
|
|
0010 011
|
6
|
0000 0011 1
|
31
|
|
0010 010
|
10
|
0000 0011 0
|
47
|
|
0010 001
|
18
|
0000 0010 1
|
55
|
|
0010 000
|
34
|
0000 0010 0
|
59
|
|
0001 1111
|
7
|
0000 0001 1
|
27
|
|
0001 1110
|
11
|
0000 0001 0
|
39
|
|
0001 1101
|
19
|
0000 0000 1
|
0 (NOTE)
|
|
NOTE — This entry shall not be used with 4:2:0 chrominance structure
|
Table B-14 --- DCT coefficients Table zero
|
Variable length code (NOTE1)
|
run
|
level
|
|
10 (NOTE 2)
|
End of Block
|
|
|
1 s (NOTE 3)
|
0
|
1
|
|
11 s (NOTE 4)
|
0
|
1
|
|
011 s
|
1
|
1
|
|
0100 s
|
0
|
2
|
|
0101 s
|
2
|
1
|
|
0010 1 s
|
0
|
3
|
|
0011 1 s
|
3
|
1
|
|
0011 0 s
|
4
|
1
|
|
0001 10 s
|
1
|
2
|
|
0001 11 s
|
5
|
1
|
|
0001 01 s
|
6
|
1
|
|
0001 00 s
|
7
|
1
|
|
0000 110 s
|
0
|
4
|
|
0000 100 s
|
2
|
2
|
|
0000 111 s
|
8
|
1
|
|
0000 101 s
|
9
|
1
|
|
0000 01
|
Escape
|
|
|
0010 0110 s
|
0
|
5
|
|
0010 0001 s
|
0
|
6
|
|
0010 0101 s
|
1
|
3
|
|
0010 0100 s
|
3
|
2
|
|
0010 0111 s
|
10
|
1
|
|
0010 0011 s
|
11
|
1
|
|
0010 0010 s
|
12
|
1
|
|
0010 0000 s
|
13
|
1
|
|
0000 0010 10 s
|
0
|
7
|
|
0000 0011 00 s
|
1
|
4
|
|
0000 0010 11 s
|
2
|
3
|
|
0000 0011 11 s
|
4
|
2
|
|
0000 0010 01 s
|
5
|
2
|
|
0000 0011 10 s
|
14
|
1
|
|
0000 0011 01 s
|
15
|
1
|
|
0000 0010 00 s
|
16
|
1
|
|
NOTE1 - The last bit 's' denotes the sign of the level, '0' for positive '1' for negative.
NOTE2 - “End of Block” shall not be the only code of t he block.
NOTE3 - This code shall be used for the first (DC) coefficient in the block
NOTE4 - This code shall be used for all other coefficients
|
Table B-14 --- DCT coefficients Table zero (continued)
|
Variable length code (NOTE)
|
run
|
level
|
|
0000 0001 1101 s
|
0
|
8
|
|
0000 0001 1000 s
|
0
|
9
|
|
0000 0001 0011 s
|
0
|
10
|
|
0000 0001 0000 s
|
0
|
11
|
|
0000 0001 1011 s
|
1
|
5
|
|
0000 0001 0100 s
|
2
|
4
|
|
0000 0001 1100 s
|
3
|
3
|
|
0000 0001 0010 s
|
4
|
3
|
|
0000 0001 1110 s
|
6
|
2
|
|
0000 0001 0101 s
|
7
|
2
|
|
0000 0001 0001 s
|
8
|
2
|
|
0000 0001 1111 s
|
17
|
1
|
|
0000 0001 1010 s
|
18
|
1
|
|
0000 0001 1001 s
|
19
|
1
|
|
0000 0001 0111 s
|
20
|
1
|
|
0000 0001 0110 s
|
21
|
1
|
|
0000 0000 1101 0 s
|
0
|
12
|
|
0000 0000 1100 1 s
|
0
|
13
|
|
0000 0000 1100 0 s
|
0
|
14
|
|
0000 0000 1011 1 s
|
0
|
15
|
|
0000 0000 1011 0 s
|
1
|
6
|
|
0000 0000 1010 1 s
|
1
|
7
|
|
0000 0000 1010 0 s
|
2
|
5
|
|
0000 0000 1001 1 s
|
3
|
4
|
|
0000 0000 1001 0 s
|
5
|
3
|
|
0000 0000 1000 1 s
|
9
|
2
|
|
0000 0000 1000 0 s
|
10
|
2
|
|
0000 0000 1111 1 s
|
22
|
1
|
|
0000 0000 1111 0 s
|
23
|
1
|
|
0000 0000 1110 1 s
|
24
|
1
|
|
0000 0000 1110 0 s
|
25
|
1
|
|
0000 0000 1101 1 s
|
26
|
1
|
|
NOTE - The last bit 's' denotes the sign of the level, '0' for positive, '1' for negative.
|
Table B-14 --- DCT coefficients Table zero (continued)
|
Variable length code (NOTE)
|
run
|
level
|
|
0000 0000 0111 11 s
|
0
|
16
|
|
0000 0000 0111 10 s
|
0
|
17
|
|
0000 0000 0111 01 s
|
0
|
18
|
|
0000 0000 0111 00 s
|
0
|
19
|
|
0000 0000 0110 11 s
|
0
|
20
|
|
0000 0000 0110 10 s
|
0
|
21
|
|
0000 0000 0110 01 s
|
0
|
22
|
|
0000 0000 0110 00 s
|
0
|
23
|
|
0000 0000 0101 11 s
|
0
|
24
|
|
0000 0000 0101 10 s
|
0
|
25
|
|
0000 0000 0101 01 s
|
0
|
26
|
|
0000 0000 0101 00 s
|
0
|
27
|
|
0000 0000 0100 11 s
|
0
|
28
|
|
0000 0000 0100 10 s
|
0
|
29
|
|
0000 0000 0100 01 s
|
0
|
30
|
|
0000 0000 0100 00 s
|
0
|
31
|
|
0000 0000 0011 000 s
|
0
|
32
|
|
0000 0000 0010 111 s
|
0
|
33
|
|
0000 0000 0010 110 s
|
0
|
34
|
|
0000 0000 0010 101 s
|
0
|
35
|
|
0000 0000 0010 100 s
|
0
|
36
|
|
0000 0000 0010 011 s
|
0
|
37
|
|
0000 0000 0010 010 s
|
0
|
38
|
|
0000 0000 0010 001 s
|
0
|
39
|
|
0000 0000 0010 000 s
|
0
|
40
|
|
0000 0000 0011 111 s
|
1
|
8
|
|
0000 0000 0011 110 s
|
1
|
9
|
|
0000 0000 0011 101 s
|
1
|
10
|
|
0000 0000 0011 100 s
|
1
|
11
|
|
0000 0000 0011 011 s
|
1
|
12
|
|
0000 0000 0011 010 s
|
1
|
13
|
|
0000 0000 0011 001 s
|
1
|
14
|
|
NOTE - The last bit 's' denotes the sign of the level, '0' for positive, '1' for negative.
|
Table B-14 --- DCT coefficients Table zero (concluded)
|
Variable length code (NOTE)
|
run
|
level
|
|
0000 0000 0001 0011 s
|
1
|
15
|
|
0000 0000 0001 0010 s
|
1
|
16
|
|
0000 0000 0001 0001 s
|
1
|
17
|
|
0000 0000 0001 0000 s
|
1
|
18
|
|
0000 0000 0001 0100 s
|
6
|
3
|
|
0000 0000 0001 1010 s
|
11
|
2
|
|
0000 0000 0001 1001 s
|
12
|
2
|
|
0000 0000 0001 1000 s
|
13
|
2
|
|
0000 0000 0001 0111 s
|
14
|
2
|
|
0000 0000 0001 0110 s
|
15
|
2
|
|
0000 0000 0001 0101 s
|
16
|
2
|
|
0000 0000 0001 1111 s
|
27
|
1
|
|
0000 0000 0001 1110 s
|
28
|
1
|
|
0000 0000 0001 1101 s
|
29
|
1
|
|
0000 0000 0001 1100 s
|
30
|
1
|
|
0000 0000 0001 1011 s
|
31
|
1
|
|
NOTE - The last bit 's' denotes the sign of the level, '0' for positive, '1' for negative.
|