Tag Image File Format (TIFF)
TIF is one of most popular graphics file formats. It is used in lots of applications for different purposes. The following parameters are used to adjust settings of this format:
- bpp - color depth (default - 32 (CMYK) bpp)
- compression - compression type (default - LZW)
- jpeg_quality - image quality (default - 85)
- jpeg_sample - channels of image compression (default - 111)
- compression_level - compression level (default - "AS IS")
- multipage - multipage option (default - "AS IS")
- quant - quantization levels (default - 8)
- dither - dithering (default - yes)
- byte_order - byte order (default - little endian)
- thumbnail - create thumbnail (default - no)
- strip - strip structure (default - Multistrip)
- exif - save EXIF (default - no)
- iptc - save IPTC (default - no)
bpp
Bpp parameter specifies the number of bits used to transfer the color of one pixel. Its allowed values are:
- 1 - 1 bpp (Mono)
- 4 - 4 bpp (Indexed)
- 8 - 8 bpp (Indexed)
- 24 - 24 bpp (True color, RGB)
- 320 - 32 bpp (CMYK)
- 32 - 32 bpp (True color, RGBA)
- 48 - 48 bpp (True color, RGB)
- 64 - 64 bpp (True color, RGBA)
The default value is: 32.
Example:
compression
Compression specifies compression algorithm for resulting files. Its allowed values are:
- NONE - resulting files are not compressed.
- CCITT_RLE - CCITT RLE algorithm is used to compress resulting files. This algorithm does not distort images but is used for monochromatic images only (color depth parameter should be set to 1).
- CCITT_Fax3 - CCITT Fax3 algorithm is used to compress resulting files. This algorithm does not distort images but is used for monochromatic images only (color depth parameter should be set to 1).
- CCITT_Fax4 - CCITT Fax4 algorithm is used to compress resulting files. This algorithm does not distort images but is used for monochromatic images only (color depth parameter should be set to 1).
- LZW - LZW algorithm is used to compress resulting files. This is the most widespread algorithm of compressing TIFF images. This algorithm does not distort images.
- FLATE - FLATE algorithm is used to compress resulting files. This modern algorithm selects compression method depending on file contents.
- JPEG - JPEG algorithm is used to compress resulting files. This is a lossy compression algorithm oriented at compressing photo-realistic full color images without any losses detected by human eye.
- JBIG - JBIG algorithm is used to compress resulting files. This algorithm is designed to compress one-bit black-and-white images and can also be used to compress four-bit images.
- JPEG6P - JPEG6 algorithm is used to compress resulting files. It is a version of JPEG algorithm.
- CCITT_RLEW - CCITT RLEW algorithm is used to compress resulting files. This algorithm does not distort images but is used for monochromatic images only (color depth parameter should be set to 1).
- PACKBITS - PackBits algorithm is used to compress resulting files. This algorithm is developed by Apple Computer, Inc. company for their Macintosh computers.
The default value is: LZW.
Example:
jpeg_quality
Jpeg_quality parameter specifies image quality. The higher is its value, the better is image quality. It can accept whole numbers from 25 to 100. The default value is: 85.
Example:
jpeg_sample
Jpeg_sample parameter specifies channels of image compression. Today most JPEG files have YcbCr format (where Y-channel stands for brightness while Cb and Cr channels stand for color). Human eye is built in such a way that it perceives brightness change of neighboring pixels first and color change next. If we write an average true color image of photo quality into JPEG format, we can skip every second horizontal value of color channels and still have an image of nearly same quality. Each two pixels of the saved image will have two values of Y channel and one value of Cb and Cr channels. In Image Converter Command Line, this write mode is specified with “sample 4:2:2” parameter. Jpeg_sample parameter can accept the following values:
- 111 - 1:1:1 - YY CbCb CrCr, YY CbCb CrCr
- 422 - 4:2:2 - YY CbCb CrCr, YY .... ....
- 421 - 4:2:1 - YY CbCb Cr.., YY .... ....
- 422 - 4:2:2 - YY CbCb CrCr, YY CbCb ....
- 411 - 4:1:1 - YY Cb.. Cr.., YY .... ....
The default value is: 111.
Example:
compression_level
Compression_level parameter specifies compression level for resulting files. Its allowed values arewhole numbers from 0 to 9. the lower is the value of compression_level, the better is image quality and the larger is file size.
Example:
multipage
Multipage parameter specifies whether resulting files should be saved as separate files or as one multipage file. Its allowed values are:
- as_is - all converted files will be saved in accordance with the structure of source files.
- separate_pages - all single-page images as well as all pages of multipage files will be saved as separate single-page files.
- multipage - all source images will be saved into one multipage file.
- append - all source images will be appended to the specified multipage file.
The default value is: as_is.
Example:
quant
Quant parameter reduces the number of distinct colors used in an image while preserving visual image quality. Allowed values of quant parameters are whole numbers from 0 to 8.
The default value is: 8.
Example:
dither
Dither is a form of noise, or 'erroneous' signal or data which is added to sample data to minimize quantization error. Allowed values of dither parameter are: yes and no.
The default value is: yes.
Example:
byte_order
Byte_order parameter specifies byte order in the resulting file. It can accept two values: little_endian � big_endian.
The default value is: little_endian.
Example:
thumbnail
Thumbnail parameter specifies whether thumbnails should be created for converted images. Thumbnails are used to preview images in browsers and graphics viewers. Its allowed values are: yes and no.
- Yes - create thumbnails.
- No - do not create thumbnails.
The default value is: No.
Example:
strip
Strip parameter specifies whether the file should be split into stripes. Its allowed values are:
- Multistrip - select this value for resulting image stripe size not to exceed 4 Kb.
- Singlestrip - select this value for resulting files to be written as one stripe.
- Tiled - select this value for resulting files to be split into random rectangles, not stripes.
The default value is: Multistrip.
Example:
exif
Exif parameter specifies whether EXIF (information on shooting parameters of the camera used) will be saved in resulting files. Its allowed values are:
- Yes - save EXIF in resulting files.
- No - do not save EXIF in resulting files.
The default value is: No
Example:
iptc
Iptc parameter specifies whether IPTC (metadata - name, copyright, category) will be saved in resulting files. Its allowed values are:
- Yes - save IPTC in resulting files.
- No - do not save IPTC in resulting files.
The default value is: No.
Example:
general example
ICPCL.exe -convertto tiff bpp:48 compression:JPEG jpeg_quality:60 jpeg_sample:422 compression_level:3 multipage:separate_pages byte_order:big_endian thumbnail:Yes strip:Singlestrip exif:Yes iptc:Yes quant:4 dither:no -source "C:\Original files" -dest "C:\Converted files"
tips
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Jpeg_quality and jpeg_sample parameters should only be used with JPEG, JBIG and JPEG 6+ compression algorithms.
Example:
ICPCL.exe -convertto tiff bpp:48 compression:JPEG jpeg_quality:60 jpeg_sample:422 -source "C:\Original files" -dest "C:\Converted files" -
Compression_level parameter should only be used with FLATE compression algorithm.
Example:
ICPCL.exe -convertto tiff bpp:48 compression:FLATE compression_level:3 -source "C:\Original files" -dest "C:\Converted files" -
EXIF information is saved in resulting files only if it exists in source files.
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IPTC data are saved in resulting files only if they exist in source files.
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When creating multipage files, the order of their pages is specified by the order of source file conversion (sorting specified with the help of -sort key).