SPRM 2: Current Subtitle Stream Number
The DVD specification allows for up to 32 different subtitle streams. This SPRM contains
two sets of values.
The first value shows which of the 32 streams is selected. These values range from 0
through 31 with 0 being the first stream and 31 being the last stream. The second value
of this SPRM is a display flag that tells you if the subtitle is turned on or off. The flag has
a value of 64 for on and 0 for off.
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Creating Scripts
To obtain the value of the stream that is selected and displayed, add 64 to the value of
the stream. For example: Stream 1 has a value of 0. If you add that value to the value of
the display flag “on” (64), you get a total of 64. Stream 2 has a value of 1; if you add the
value of the display flag on (64) to it, you get a total of 65.
The following table lists the possible settings for SPRM 2:
SPRM 2 value with the stream
selected and display on
SPRM 2 value with the stream
selected and display off
Stream number
64
0
1
65
1
2
66
2
3
67
3
4
68
4
5
69
5
6
70
6
7
71
7
8
72
8
9
73
9
10
74
10
11
75
11
12
76
12
13
77
13
14
78
14
15
79
15
16
80
16
17
81
17
18
82
18
19
83
19
20
84
20
21
85
21
22
86
22
23
87
23
24
88
24
25
89
25
26
90
26
27
91
27
28
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SPRM 2 value with the stream
selected and display on
SPRM 2 value with the stream
selected and display off
Stream number
92
28
29
93
29
30
94
30
31
95
31
32
Similar to SPRM 1, this information is useful to determine the last subtitle stream selected
by the viewer. If you have a menu for subtitle selection, you can use this information to
highlight the corresponding button for the correct subtitle.