TIFF 6.0 Specification
Final—June 3, 1992
tile contains an integral number of restart intervals. Restart markers need not be
present in a TIFF file; they are implicitly coded at the start of every strip or tile.
To maximize interchangeability of TIFF files with other formats, a restriction is
placed on tile height for files containing JPEG-compressed image data conform-
ing to the JPEG interchange format syntax. The restriction, imposed only when
the tile width is shorter than the image width and when the
JPEGInterchangeFormat Field is present and non-zero, states that the tile height
must be equal to the height of one JPEG Minimum Coded Unit (MCU). This
restriction ensures that TIFF files may be converted to JPEG interchange format
without undergoing decompression.
Extensions to Existing Fields
Compression
Tag
= 259 (103.H)
Type = SHORT
N
=1
This Field indicates the type of compression used. The new value is:
6 = JPEG
JPEG Fields
JPEGProc
Tag
Type
N
= 512 (200.H)
= SHORT
=1
This Field indicates the JPEG process used to produce the compressed data. The
values for this field are defined to be consistent with the numbering convention
used in ISO DIS 10918-2. Two values are defined at this time.
1= Baseline sequential process
14= Lossless process with Huffman coding
When the lossless process with Huffman coding is selected by this Field, the
Huffman tables used to encode the image are specified by the JPEGDCTables
field, and the JPEGACTables field is not used.
Values indicating JPEG processes other than those specified above will be de-
fined in the future.
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