standard defines a method of dealing with thumbnail images. This however is different from the method that is used in the Exif standard. Several tags defined by the Exif standard have been re-defined in the TIFF/EP standard – see table below. Compression Images in TIFF/EP files may be stored in uncompressed form, or using JPEG baseline DCT-based lossy compression. TIFF/EP also allows usage of other compression methods, but TIFF/EP readers are not required to decompress these images. All TIFF/EP readers shall support the DCT (lossy) baseline version of the TIFF/JPEG compression method described in TIFF 6.0 Technical note #2. The JPEG compression is indicated using a value of 000716 in the Compression tag-field as a binary value. There may be more than one image (subfile) in a TIFF 6.0 file. Each subfile is defined by Image File Directory (IFD). If an image compression method is used in TIFF/EP, an uncompressed Baseline TIFF-readable "thumbnail" image (with a reduced-resolution) should also be stored in the 0th IFD of TIFF/EP, to allow the images to be viewed and identified using a Baseline TIFF 6.0 reader. (Note: JPEG compression is not required for Baseline TIFF 6.0 readers.) TIFF/EP files may optionally use lossless JPEG compression and other JPEG compressions, but TIFF/EP readers are not required to decompress these images. If the lossless JPEG compression is used, the recommended form is lossless sequential DPCM using Huffman coding. TIFF/EP files may also optionally support vendor unique compression, but TIFF/EP readers are only required to open the uncompressed "thumbnail" image that may be present in IFD0. Proprietary compression methods can be used by obtaining a private compression tag value from the TIFF administrator (Adobe). TIFF/EP complies with the TIFF 6.0 specification. The reason is to maintain compatibility with existing TIFF readers, and to make the adoption of TIFF/EP as easy as possible. The TIFF Tag 259 (010316) stores the information about the Compression method. Its use is mandatory in TIFF/EP. There is no default value in TIFF/EP, but the tag value shall equal "000116" for the thumbnail IFD. The following is a list of defined TIFF/EP compression schemes: Timeline for development and revision Dates limited to publicly available sources: See also Tagged Image File Format (TIFF) Exchangeable image file format (Exif) Design rule for Camera File system International Organization for Standardization List of ISO standards References External links ISO 12234-2:2001 Electronic still-picture imaging – Removable memory –