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Redbook Format


Redbook format is broken into general purpose blocks.  Each block is defined as follows:

Halfword Content Description
0 LCllllllllll... L - length flag - 0 if length included
C - Checksum flag - 0 if checksum included
llll... - length field - 14 bit length in halfwords (2 bytes)
1 mode submode Mode and submode values that define block type
2-nnn     Data
nnn Checksum  

These blocks are repeated until end of product


1. Product Data

1.1 Product Identification Block (mode 1, submode 1)

Halfword Content Description
1 1 1 Mode and submode
2 C1 C2 Originator identification (4 characters)
3 C3 C4  
4 Classification Retention time Classification -
U - unclassified
C - confidential
S - secret
T - top secret
E - encrypted

Retention time - default time in days to retain product

5 File indicator C2 File indicator determines originating agency
6 C3 C4 Product identifier C2-C10 - used to determine type of data
7 C5 C6  
8 C7 C8  
9 C9 C10  
10 Year  
11 Month Day  
12 Hour Minute  
13 C11 C12 Additional product identifier
14 C13 C14  
15 C15 C16  

1.2 End of Product Block (mode 1, submode 2)

Halfword Content Description
1 1 2 Mode and submode

1.4 Plot Parameters Block (mode 1, submode 4)

This defines various plotting parameters.  Not all parameters need to be specified.

Halfword Content Description
1 1 4 Mode and submode
2 Z threshold zoom factor Z - zoom disable:
0 - data are sized according to zoom
1 - data are displayed invariant of zoom

threshold - minimum zoom factor needed to display data
0 - display at all zoom levels
1 - display only at 1X or higher magnifications

factor - optional zoom factor applied to strings at local level

3 plot color background color Color index values
4 line char line width line char:
0 - continuous
1 - dotted
2 - short dashed
3 - long dashed
4 - dotted (every 4th pixel)
5 - symbolic line

line width - width of line in pixels

5 C1 C2 Line mneumonic (4 characters)
6 C3 C4
7 logical fill fill pattern logical fill - Flag indicating whether fill is to be done on the "L" left or "R" of vector string

fill pattern - A preassigned pattern number


2. Systems Data

These are user defined fields.


3. Formatted Binary Data


4. Vector Graphics Data

These blocks are used with vector graphics plots.

4.16 Vector Graphics Definition Block (mode 4, submode 16)

Halfword Content Description
1 4 16 Mode and submode values
2 PI set coord flag PI - projection indicator - defines the background projection

coord flag:
0 - M=latitude, N=longitude
1 - M=I, N=J, Cartesian coordinates
2 - M=X, N=Y, Pixel coordinates

3 area code label code area code - defines the reference points

label code:
0 - label codes are non-standard and will be sent in alphanumeric block
1 - standard user define label

4 M1 First reference coordinate (M,N), defined by area code
5 N1  
6 M2 Second reference coordinate (M,N)
7 N2  
8 M3 Third reference coordinate (M,N)
9 N3  
10 Month Day Valid Time
11 Hour Minute  
12 Month Day End of valid period
13 Hour Minute  

Projection Indicators:

The projection is a grid that is defined by a scale (distance between gridpoints) and a lower left corner position (X0,Y0).

PI Description Projection LongX Scale X0 Y0
21 Northern Hemisphere Polar Stereographic 105W .0508 -61.5 -83.7
22 North America Polar Stereographic 105W .1016 -103 -86

Area Codes:

11 - One reference point is used to define the upper left corner of the product
12 - One reference point is used to define the lower left corner of the product
13 - One reference point is used to define the center of the product
21 - Two reference points are used to define the upper left and upper right corners of the product
22 - Two reference points are used to define the lower left and upper right corners of the product
23 - Two reference points are used to define the upper left and center of the product
24 - Two reference points are used. The first reference point gives the coordinates of the lower left corner of the product in units of the grid from which it was extracted.   The second set of reference coordinates will give the maximum horizontal and maximum vertical size of the product in pixels.
25 - Same as 25 except the reference point is located at the center of the product.
33 - Three reference points are used to define the upper left, upper right, and lower right corners of the product.

4.1 Absolute Vectors Block (mode 4, submode 1)

Halfword Content Description
1 4 1 Mode and submode values
2 M0 First coordinate (M,N) of the line
3 N0  
4 B  M1 B - beam flag:
0 - pen up, new line starts
1 - pen down, line drawn to previous point

Second coordinate (M,N)

5 N1  
6-nnn Mx,Nx Successive coordinates

4.2 Relative Vectors Block (mode 4, submode 2)

Halfword Content Description
1 4 2 Mode and submode values
2 M0 First coordinate (M,N) of the line
3 N0  
4 dM1 dN1 Delta M,N values.  Successive values are added to previous values.  The delta values are in two's complement.
5-nnn dMx dNx Successive delta values.

4.5 Long/Short Relative Vectors Block (mode 4, submode 5)

This is similar to the relative vector block except that it allows deltas to be either a long or short value.  The long deltas are 2 halfwords and the short deltas are 1 halfword.

Halfword Content Description
1 4 5 Mode and submode values
2 M0 First coordinate (M,N) of the line
3 N0
4 1 dM1 B dN1 1 - denotes short delta values. 

dM1 - 7 bit delta M (two's complement).

B - beam mode: 0 - pen up, new line, 1 - pen down draw from previous point

dN1 - 7 bit delta N (two's complement)

Delta M,N values.  Successive values are added to previous values.  The delta values are in two's complement.

4 0xx  dM1 0xx - denotes long delta values.

dM1 - 15 bit delta M (two's complement)

5 0xB  dN1 B - beam mode: 0 - pen up, new line, 1 - pen down draw from previous point

dN1 - 15 bit delta M (two's complement)

5-nnn Successive delta values.

4.10 Curve Vectors Block (mode 4, submode 10)

This specifies a list of point to which a smooth curve is to be fitted.  There is a minimum of three points.

Halfword Content Description
1 4 10 Mode and submode values
2 M0 First coordinate (M,N) of the line
3 N0  
4 B  M1 B - beam flag:
0 - pen up, new line starts
1 - pen down, line drawn to previous point

Second coordinate (M,N)

5 N1  
6 B  M2 Third coordinate (M,N)
7 N2  
8-nnn Mx,Nx Successive coordinates

5. Alphanumeric Data

5.16 Alpanumeric Product Definition Block (mode 5, submode 16)

Halfword Content Description
1 5 16 Mode and submode values
2-nnn C1 C2 Character data. Number of characters defined by block length.

5.1 Alphanumeric Character Block (mode 5, submode 1)

Halfword Content Description
1 5 1 Mode and submode values
2 M Position (M,N) of the string
3 N  
4 dM dN Delta M,N values identify offset from position for the first character in the string.  This is fixed regardless of zoom factor.
5 B R size C1 B - Block mode:
0 - display normally (except with R=1)
1 - rectangular block is cleared prior to plotting text.

R - Reverse mode:
0 - normal display
1 - reverse mode

size - Character size factor in display units: 0 = standard size, 1 = 5x7, 2 = 10x14, 3 = 15x21, etc.

C1 - Start of character data.

6-nnn C2 C3 Additional character data. Number of characters defined by block length.

5.2 Plot Data Block (mode 5, submode 2)

The plot data block plots data based on a process code.  This can define strings or symbols to be plotted.  In the case of symbols, the process code defines the number of characters needed to define the symbol.  More than one can be plotted.  

Halfword Content Description
1 5 2 Mode and submode values
2 B R size code B - Block mode:
0 - display normally (except with R=1)
1 - rectangular block is cleared prior to plotting text.

R - Reverse mode:
0 - normal display
1 - reverse mode

size - Character size factor in display units: 0 = standard size, 1 = 5x7, 2 = 10x14, 3 = 15x21, etc.

code - Plot process code

3 M Position (M,N) of the string
4 N  
5 C1 C2 Characters to be plotted based on process code.
6 C3 C4
7-xxx Cx Cx
xxx+1 M Position (M,N) of the next string
xxx+2 N  
xxx+3 C1 C2 Characters to be plotted based on process code.
xxx+4 C3 C4
xxx+5-yyy Cx Cx

Process Codes:

0 - Character data.  M,N is lower left corner of first character.
1 - Weather symbols.  Each symbol is determined from a 4 character mneumonic.   M,N is the lower left corner of the symbol. 
2 -


6. Rastor Scan Data


7. Gridded Data