TIF: Tagged Image File Format



Several companies developed the Tagged Image Format, including Aldus and Silicon Graphics, to be the be-all and end-all of image file formats. Because of its scope and extensibility, it is an extremely complex format that no single product can support completely.


The known TIFF formats not currently handled by ThumbsPlus are:


Images in YCbCr (YUV) or proprietary color formats.
Alpha channels (extra samples) are discarded when reading.


The following compression methods and special-interest formats are supported:


Multi-image TIFFs (Using the paging selections on the Edit menu selections, ThumbsPlus can view any of the images in a multi-image TIFF file, and can split the pages into separate files.)
Tiled TIFFs.
CCITT RLE, Group 3, and Group 4 Fax compression.
Packbits, Thunderscan and Next compression.
LZW compression.
Motorola (MM) format.
JPEG compression (post TIFF 6.0 format).
ZIP "deflate" mode compression (experimental).
CIE L*a*b colorspace TIFF files.
16-bit grayscale and 48-bit color TIFF file.


ThumbsPlus writes uncompressed TIFFs, or compressed via CCITT Group 3 or 4 FAX, Packbits, JPEG, ZIP, or LZW.


IPTC/NAA information, stored by Adobe Photoshop and other software, can be extracted from TIFF files and displayed in File | Properties | Info. ThumbsPlus retains the information if the file is written or converted to JPEG format.