Eicon Networks Network Device 206-412-06 - Manual (Page 10)

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Line Length word Number of pixels per line
1728: standard fax G3
2048: B4 (optional)
2432: A3 (optional)
Support for additional values is optional for COMMON-
ISDN-API
If FAX paper formats and resolutions are enabled
1728: ISO A4 at R8 x 3.85, R8 x 7.7, R8 x 15.4, 200 x 200
2048: ISO B4 at R8 x 3.85, R8 x 7.7, R8 x 15.4, 200 x 200
2432: ISO A3 at R8 x 3.85, R8 x 7.7, R8 x 15.4, 200 x 200
2592: ISO A4 at 300 x 300, 300 x 600
3072: ISO B4 at 300 x 300, 300 x 600
3648: ISO A3 at 300 x 300, 300 x 600
3456: ISO A4 at R16 x 15.4, 400 x 400, 400 x 800
4096: ISO B4 at R16 x 15.4, 400 x 400, 400 x 800
4864: ISO A3 at R16 x 15.4, 400 x 400, 400 x 800
5184: ISO A4 at 600 x 600, 600 x 1200
6144: ISO B4 at 600 x 600, 600 x 1200
7296: ISO A3 at 600 x 600, 600 x 1200
10368: ISO A4 at 1200 x 1200
12288: ISO B4 at 1200 x 1200
14592: ISO A3 at 1200 x 1200
Page Length word Number of pixel lines per page. If not known, coded as
0x0000.
OffsetPreviousPage dword Byte offset to previous page header or 0x00000000. Coded as
0x00000001 if first page.
OffsetNextPage dword Byte offset to next page header or 0x00000000. Coded as
0x00000001 if last page.
B.2.3 Page data
Page data are coded line by line: data describes each pixel row. Lines are coded as
records of variable length; each line is coded according to the element coding in the
page header. At present, only modified Huffman coding is supported. MH coding is
bit-oriented: the pixel bits are stored in the bits of code words least significant first. No
EOL code words or fill bits are included. If the data include EOL code words,
COMMON-ISDN-API ignores these.
Each record is identified by the first byte:
• 1...216: a pixel row with 1...216 MH-coded bytes follows immediately
• 0: escape code for a pixel row with more than 216 MH-coded bytes. In this case, the following
word in the range 218...32767 defines the number of MH-coded bytes which follow.
• 217...253: white space, skip 1...37 empty lines
• 254: start of page header (see above)
• 255: if followed by a byte with value 0, illegal line coding. Applications may choose whether
to interpret this line as empty or as a copy of the previous line. If this byte is followed by a byte
with a value 1...255, then 1...255 bytes of additional user information follow (reserved for
future extensions).