TIFF 6.0 Specification
Final—June 3, 1992
• TIFF is compatible with compressed image data that conforms to the syntax of
the JPEG interchange format for compressed image data. Fields are defined
that may be utilized to facilitate conversion from TIFF to interchange format.
• The PlanarConfiguration Field is used to specify whether or not the com-
pressed data is interleaved as defined by JPEG. For any of the JPEG DCT-
based processes, the interleaved data units are coded 8x8 blocks rather than
component samples.
• Although JPEG codes consecutive image blocks in a single contiguous
bitstream, it is extremely useful to employ the concept of tiles in an image. The
TIFF Tiles section defines some new fields for tiles. These fields should be
stored in place of the older fields for strips. The concept of tiling an image in
both dimensions is important because JPEG hardware may be limited in the
size of each block that is handled.
• Note that the nomenclature used in the TIFF specification is different from the
JPEG Draft International Standardittee Draft (ISO DIS 10918-1) in some
respects. The following terms should be equated when reading this Section:
TIFF name
ImageWidth
ImageLength
SamplesPerPixel
JPEGQTable
JPEGDCTable
JPEGACTable
JPEG DIS name
Number of Pixels
Number of Lines
Number of Components
Quantization Table
Huffman Table for DC coefficients
Huffman Table for AC coefficients
Strips and Tiles
The JPEG extension to TIFF has been designed to be consistent with the existing
TIFF strip and tile structures and to allow quick conversion to and from the
stream-oriented compressed image format defined by JPEG.
Compressed images conforming to the syntax of the JPEG interchange format can
be converted to TIFF simply by defining a single strip or tile for the entire image
and then concatenating the TIFF image description fields to the JPEG compressed
image data. The strip or tile offset field points directly to the start of the entropy
coded data (not to a JPEG marker).
Multiple strips or tiles are supported in JPEG compressed images using restart
markers. Restart markers, inserted periodically into the compressed image data,
delineate image segments known as restart intervals. At the start of each restart
interval, the coding state is reset to default values, allowing every restart interval
to be decoded independently of previously decoded data. TIFF strip and tile off-
sets shall always point to the start of a restart interval. Equivalently, each strip or
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