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Sliced VBI data
[Raw VBI]

Definition of sliced VBI data. More...

Data Structures

struct  vbi_sliced
 This structure holds one scan line of sliced vbi data. More...


Data service symbols

#define VBI_SLICED_NONE   0
#define VBI_SLICED_TELETEXT_B_L10_625   0x00000001
#define VBI_SLICED_TELETEXT_B_L25_625   0x00000002
#define VBI_SLICED_TELETEXT_B   (VBI_SLICED_TELETEXT_B_L10_625 | VBI_SLICED_TELETEXT_B_L25_625)
#define VBI_SLICED_VPS   0x00000004
#define VBI_SLICED_CAPTION_625_F1   0x00000008
#define VBI_SLICED_CAPTION_625_F2   0x00000010
#define VBI_SLICED_CAPTION_625   (VBI_SLICED_CAPTION_625_F1 | VBI_SLICED_CAPTION_625_F2)
#define VBI_SLICED_CAPTION_525_F1   0x00000020
#define VBI_SLICED_CAPTION_525_F2   0x00000040
#define VBI_SLICED_CAPTION_525   (VBI_SLICED_CAPTION_525_F1 | VBI_SLICED_CAPTION_525_F2)
#define VBI_SLICED_2xCAPTION_525   0x00000080
#define VBI_SLICED_NABTS   0x00000100
#define VBI_SLICED_TELETEXT_BD_525   0x00000200
#define VBI_SLICED_WSS_625   0x00000400
#define VBI_SLICED_WSS_CPR1204   0x00000800
#define VBI_SLICED_VBI_625   0x20000000
#define VBI_SLICED_VBI_525   0x40000000

Functions

const char * vbi_sliced_name (unsigned int service)

Detailed Description

Definition of sliced VBI data.

The output of the libzvbi raw VBI decoder, and input to the data service decoder, is VBI data in binary format as defined in this section. It is similar to the output of hardware VBI decoders and VBI data transmitted in digital TV streams.


Define Documentation

#define VBI_SLICED_NONE   0
 

No data service, blank vbi_sliced structure.

#define VBI_SLICED_TELETEXT_B   (VBI_SLICED_TELETEXT_B_L10_625 | VBI_SLICED_TELETEXT_B_L25_625)
 

Teletext System B.

Note this is separated into Level 1.0 and Level 2.5+ since the latter permits occupation of PAL/SECAM scan line 6 which is frequently out of range of raw VBI capture drivers. Clients should request decoding of both, may then verify Level 2.5 is covered. Also sliced data can be tagged as both Level 1.0 and 2.5+, i. e. VBI_SLICED_TELETEXT_B.

Reference: ETS 300 706 "Enhanced Teletext specification".

vbi_sliced payload: Last 42 of the 45 byte Teletext packet, that is without clock run-in and framing code, lsb first transmitted.

#define VBI_SLICED_VPS   0x00000004
 

Video Program System.

Reference: ETS 300 231 "Specification of the domestic video Programme Delivery Control system (PDC)" .

vbi_sliced payload: Byte number 3 to 15 according to Figure 9, lsb first transmitted.

#define VBI_SLICED_CAPTION_625   (VBI_SLICED_CAPTION_625_F1 | VBI_SLICED_CAPTION_625_F2)
 

Closed Caption for 625 line systems (PAL, SECAM).

Note this is split into field one and two services since for basic caption decoding only field one is required. Clients should compare the vbi_sliced line number, not the type to determine the source field.

Reference: EIA 608 "Recommended Practice for Line 21 Data Service".

vbi_sliced payload: First and second byte including parity, lsb first transmitted.

#define VBI_SLICED_CAPTION_525   (VBI_SLICED_CAPTION_525_F1 | VBI_SLICED_CAPTION_525_F2)
 

Closed Caption for 525 line systems (NTSC).

Note this is split into field one and two services since for basic caption decoding only field one is required. Clients should compare the vbi_sliced line number, not the type to determine the source field. VBI_SLICED_CAPTION_525 also covers XDS (Extended Data Service), V-Chip data and ITV data.

Reference: EIA 608 "Recommended Practice for Line 21 Data Service".

vbi_sliced payload: First and second byte including parity, lsb first transmitted.

#define VBI_SLICED_2xCAPTION_525   0x00000080
 

Closed Caption at double bit rate.

Reference: ?

vbi_sliced payload: First to fourth byte including parity bit, lsb first transmitted.

#define VBI_SLICED_NABTS   0x00000100
 

North American Basic Teletext Specification.

(Supposedly this standard fell into disuse.)

Reference: EIA-516 "North American Basic Teletext Specification (NABTS)".

vbi_sliced payload: 33 bytes.

#define VBI_SLICED_TELETEXT_BD_525   0x00000200
 

?

Reference: ?

vbi_sliced payload: 34 bytes.

#define VBI_SLICED_WSS_625   0x00000400
 

Wide Screen Signalling for 625 line systems (PAL, SECAM)

Reference: EN 300 294 "625-line television Wide Screen Signalling (WSS)".

vbi_sliced payload:

 Byte         0                  1
       msb         lsb  msb             lsb
 bit   7 6 5 4 3 2 1 0  x x 13 12 11 10 9 8
according to EN 300 294 Table 1, lsb first transmitted.

#define VBI_SLICED_WSS_CPR1204   0x00000800
 

Wide Screen Signalling for NTSC Japan

Reference: EIA-J CPR-1024 (?)

vbi_sliced payload:

 Byte         0                    1                  2
       msb         lsb  msb               lsb  msb             lsb
 bit   7 6 5 4 3 2 1 0  15 14 13 12 11 10 9 8  x x x x 19 18 17 16
 

#define VBI_SLICED_VBI_625   0x20000000
 

No actual data service. This symbol is used to request capturing of all PAL/SECAM VBI data lines from the libzvbi driver interface, as opposed to just those lines used to transmit the requested data services.

#define VBI_SLICED_VBI_525   0x40000000
 

No actual data service. This symbol is used to request capturing of all NTSC VBI data lines from the libzvbi driver interface, as opposed to just those lines used to transmit the requested data services.


Function Documentation

const char* vbi_sliced_name unsigned int  service  ) 
 

Parameters:
service A VBI_SLICED_ symbol, for example from a vbi_sliced structure.
Returns:
Name of the service, ASCII, or NULL if unknown.


Generated on Thu Aug 26 18:28:55 2004 for ZVBI Library by doxygen 1.3.7