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EXIFPROBE(1)		    General Commands Manual		  EXIFPROBE(1)

       exifprobe  -  probe and report structure	and metadata content of	camera
       image files

       exifprobe [options] filename(s)

       Exifprobe reads image files produced by digital cameras (including sev-
       eral  so-called	"raw"  file  formats) and reports the structure	of the
       files and the auxilliary	data and metadata contained  within  them.  In
       addition	 to TIFF, JPEG,	and EXIF, the program understands several for-
       mats which may contain "raw"  camera  data,  including  MRW,  CIFF/CRW,
       JP2/JPEG2000,  RAF,  and	 X3F,  as well as most most TIFF-derived "raw"
       formats,	including DNG, ORF, CR2, NEF, K25/KDC/DCR, and PEF. Other TIFF
       or JPEG-derived formats (which begin with a TIFF	header or JPEG marker)
       should also be readable.	 The program attempts to display ALL  informa-
       tion  in	 the image file, in a manner which mimics the structure	of the
       file as closely as possible.

       Where possible, output is not limited to	"known"	data items.  I.e.  for
       tagged  file formats, unknown tags will be identified by	tag number and
       type, and values	shown without interpretation. Proprietary, untagged or
       fixed  format  files  do	not permit this, but unknown or	undefined data
       can usually be dumped in	a hex/ascii format for examination, so long as
       the  file structure is understood. The program will report the contents
       of any properly structured TIFF IFD or CIFF directory encountered, even
       when entry tags are not recognized.  Recognized TIFF, TIFF/EP, DNG, and
       CIFF tags are expanded, including EXIF2.2 sections  and	camera	Maker-
       Notes  which are	found to be in TIFF IFD	format.	 TIFF and/or JPEG sec-
       tions found in MRW, RAF or JP2 files will be reported, along  with  the
       "native"	 sections of those formats. JP2	boxes will be reported whether
       known or	unknown, and expanded if known.	 Unknown boxes cannot  be  ex-
       panded, since JP2 is not	tagged below the box (or sub-box) level.

       An effort is made to identify all sub-images (in	any image format) con-
       tained in multi-image files; the	location, size,	and format of such im-
       ages  is	 reported,  and	 a hex/ascii dump of the image data may	be re-
       quested.	Image data is not processed, but the  program  will  recognize
       and  report all standard	JPEG and JPEG2000 markers (including JPEG APPn
       markers)	and will expand	APP0 (JFIF/JFXX) and APP1 (EXIF) sections.

       Since the program does not attempt to display images or modify the con-
       tents  of  files, it can	often recover from and report failures or warn
       about structural	oddities which would confuse a display or  image  edit

       There are a wide	variety	of output formats, selectable in detail	by the
       "lower case" options described in the OPTIONS section below.  These op-
       tions  select which items to print, and within narrow confines, how and
       where to	print them.  A large number of combinations of options	exist,
       and  some of those combinations may not be sensible.  In	order to avoid
       the need	for constant creativity	or  invention,	three  "prefabricated"
       output formats are provided, selected by	the upper case option letters.

       The  structural	(-S) output format (default) provides a	description of
       the image file which mimics as  closely	as  possible  the  layout  and
       structure  of  the  data	 in  the image file, including file offsets of
       headers,	section	and segment markers, fully described TIFF  IFDs,  CIFF
       directories,  or	 JP2  boxes,  and  the location	of actual image	and/or
       thumbnail data.	The contents of	each section are indented relative  to
       the  beginning  of  the	section, and "offset" values for TIFF IFDs and
       CIFF directories	are reported at	the offsets where they are found (usu-
       ally  following the entry list for TIFF,	or in the HEAP for CIFF).  The
       peculiar	"reverse" structures of	CIFF and X3F formats are handled  sen-

       The report format (-R) shows the	"logical" structure of the image file,
       but eliminates addresses, offsets, IFD value types  and	counts,	 etc.,
       and prints "offset" directory values inline, while otherwise preserving
       the primary structure of	the data.

       The list	format (-L) omits all structural data. It  writes  only	 "tag"
       values from TIFF, Exif, and MakerNote IFDs, CIFF	or other format	direc-
       tories or JP2 boxes, including section and  image  offsets  and	sizes.
       Identifiable  values  from  non-tagged formats are written in a similar
       manner.	This format may	be useful for extracting information for photo

       The  structural format is default.  This	format provides	maximum	infor-
       mation about the	contents of an image file, and may reveal  information
       (sometimes  important) which other formats (or image info programs) may

       In all formats, the filename, file type,	file size, an  image  summary,
       and a summary file format will be displayed (even when all other	output
       is disabled by option). The image summary includes  a  summary  report,
       for  each  subimage  found, giving the image type, compression type (if
       any), pixel size, data length, file offset where	found, and section  of
       the  file which includes	or references the image.  In some cases, short
       remarks may be included for images mentioned but	not  found,  etc.  The
       summary concludes with the number of images found, and number of	images
       not found (if any). The summary is followed by a	listing	of format sec-
       tions  found  (TIFF/JPEG/EXIF, etc.) and	a type identifier for TIFF-de-
       rived types (e.g. CR2) where possible.

       An environment variable may be set to a list of	options	 to  customize
       the default output behavior (see	below).

       Camera-generated	 images	 which	contain	EXIF sections may also contain
       sections	introduced by a	MakerNote tag, which may  contain  information
       about  camera  or  firmware  settings  used  to produce the image.  The
       structure and contents of MakerNote sections is	not  mandated  by  the
       Exif  specification, but	many camera MakerNotes are written in TIFF IFD
       format, possibly	offset following an ID string or new TIFF  header  (or
       both),  and  sometimes with inventive handling of "offsets".  Exifprobe
       currently understands and automatically detects such schemes and	prints
       the  contents  of the IFD (and the ID string, if	present).  This	detec-
       tion is not dependent upon make or model	of camera.  Make and Model in-
       formation  will	usually	 be  available	from the first TIFF IFD	in the
       file; this information may be used to interpret the MakerNote  informa-
       tion for	"known"	cameras; otherwise, tag	numbers, sizes,	types, and raw
       values from the IFD will	be shown (if permitted by option settings).

       Some camera makes are known to use more than one	version	of  MakerNote,
       depending  upon	model.	If an unknown model from that maker is encoun-
       tered, the note will be briefly examined	and a noteversion assigned au-
       tomatically  if	possible.   If	that fails, the	note will be displayed
       without interpretation.

       MakerNotes which	are not	in a recognizable IFD format will be  reported
       (start  and  end	 offsets) in structural	(-S) and report	(-R) formats ,
       and the beginning of the	note section hex/ascii dumped.	The  remainder
       of  the	note may be dumped, in whole or	in part, by the	-M option (see

       In list (-L) format, the	starting file offset and  length  supplied  by
       the  MakerNote  tag will	be reported, and three "pseudo"	tags which re-
       port the	offset (MakerNote.Offset), size	(MakerNote.Length) and	scheme
       (MakerNote.Scheme) will appear.

       In JPEG interchange format files, APP0 (JFIF,JFXX) and APP1 (Exif) seg-
       ments will be fully decoded, and	the "printable"	portions of APP12 sec-
       tions  will be displayed. APP3 (Meta) sections will be expanded and the
       contained TIFF IFD will be displayed, although little interpretation is
       done.  Other  APP  markers  will	 be  reported, and the sections	may be
       hex/ascii dumped	in whole or in part using the -A option. APP1 sections
       not marked as Exif will be treated as unknown.

   ANSI	Color
       The program (by default)	emits ANSI color escape	sequences to highlight
       Exif, MakerNote , and Interoperability sub-sections.  Errors and	 warn-
       ings are	highlighted in red.  These sequences are effective, of course,
       only for	terminals or terminal emulators	(e.g. xterm) which respond  to
       ANSI  color escape sequences.  If a pager is used to display the	output
       when these sequences are	present, a "raw" option	to the	pager  may  be
       required	 (e.g. less -R).  The use of these sequences may be toggled by
       the -c option.  LIST mode turns color sequences off.

       The program may be compiled without support for color sequences.

       In all formats, and regardless of option	setting, the first three lines
       of  output  for each file processed are the filename, image type	(TIFF,
       CIFF, JP2, etc.), and the file size.  If	the type (taken	from the  file
       header)	specifies  a data byte order, the byte order will be indicated
       with the	type as	`II' (Intel byte order)	or `MM'	(Motorola byte order).
       The image summary and summary format will always	be printed at the end.

   Structural Format
       Structural format output	begins with a display of the file header.  The
       header is followed by lines of the form
       etc.  to	indicate the beginning and end of each "section" of the	 file.
       Actual  section	names  will,  of  course,  depend upon the file	format
       and/or the tags encountered.  Only the TIFF  IFD	 format	 is  described
       here;  other formats are	similar, except	that JP2 box names are printed
       inside square (rather than angle) brackets, and MRW section  names  in-
       side curly braces.

       Within  sections,  directory  entries,  subdirectories, the contents of
       known APP sections, JPEG	segment	markers, etc. are  printed.   Non-jpeg
       image data sections will	be shown with a	few lines of hex/ascii dump of
       the beginning of	the data.

       Each line of output is preceded by a file offset	given in hex and deci-
       mal.   File offsets are preceded	by the character `@', except that sec-
       tion end	markers	are preceded by	`-' and	the character `>' may be  used
       to  mark	 sections  which are located outside the IFD in	which they are
       declared.  If that section includes a subsection	which is similarly af-
       flicted,	 the  '>' is replaced by '+' in	the subsection.	 In JP2	files,
       the '@' is replaced by '=', for no particular reason.

       JPEG and	JPEG2000 segment markers are written with the marker name, and
       the decoded values of any information associated	with the marker.

       TIFF information	is written in a	manner which reflects the structure of
       the IFD,	with all values	interpreted according to the applicable	speci-
       fication	 where	possible.  All IFD fields are reported.	 The following
       fields will appear on each line (in the order given, following the file

       o      Tag  number  in  hex  and	 decimal  representations, enclosed in

       o      Tag name (where known); names for	unknown	tags are created as  a
	      hex  representation  of  the  tag	 number	prefixed by the	string

       o      The TIFF type number, name, and byte count  for  the  associated
	      value, enclosed in square	brackets.

       o      The "value/offset" for the entry.	 If the	value fits in the four
	      bytes of the entry, the value is printed directly.

	      If the value for the entry did not fit in	the four bytes of  the
	      entry,  then the value found is an offset	to the actual location
	      of the data; that	offset is printed preceded by an  '@'  symbol.
	      The actual value will be printed later, at the file offset where
	      it was found (except in some non-conforming MakerNote IFDs).  If
	      the  value requires interpretation (e.g. TIFF Orientation) it is
	      followed by an '=' sign and the interpretation, enclosed in dou-
	      ble quotes (e.g. "0,0 top	left").

       The list	of entries will	be followed by a line giving the offset	to the
       next IFD	(often 0) which	is always found	at the end of a	TIFF IFD entry

       If  there  were	offset	entries	found in the list above, the TIFF (and
       Exif) specification requires that they will  be	located	 next  in  the
       file,  immediately  following  the dirctory entries.  This stricture is
       frequently ignored in MakerNotes	and TIFF-derived formats.  A line  re-
       porting	the  beginning	of these offset	values will be printed immedi-
       ately after the next IFD	offset,	followed by one	line for  each	offset
       entry,  with  the tag name repeated, followed by	the actual value, fol-
       lowed by	its interpretation (if any).

       Multiple	values in entries are printed on  a  single  line,  but	 large
       lists  will  be	elided,	with just the first two	or three values	shown,
       followed	by an ellipsis,	followed by the	last value, the	number of val-
       ues, and	the offset of the last value in	the list.  The full value list
       may be printed using the	-eA option.

       In structural format, ascii strings in the entry	are  printed  for  the
       entire  length  given  in  the IFD entry, including nulls and non-ascii
       values (if present), which are printed in `backslashed' octal notation.
       The  -ea	option may be used to force ascii values to be printed only up
       to the first null.  This	option is  often  necessary  for  CIFF	format
       files, and is enabled by	default	in "list" mode.

       Entries	are  indented  slightly	from the start identifier for the IFD,
       and subsegments (e.g. an	Exif IFD, SubIFD, or MakerNote)	will  be  fur-
       ther indented in	order to indicate the structure	of the file.

       The  resulting  output  displays	the contents of	the IFD	much as	it ap-
       pears in	the file (see the TIFF or EXIF specifications for descriptions
       of the IFD format).

       Finally,	 the  start and	end of actual image data for the primary image
       (and possibly thumbnail or reduced-resolution image) is reported	at the
       end.   For  JPEG	images,	this usually includes display of the JPEG seg-
       ment markers within the image.  Binary format image data	will be	 shown
       with a brief hex/ascii dump of the beginning of the data, between start
       and end markers.

       Note that values	preceded by `@'	are always offsets from	the  beginning
       of  the	file to	the actual value.  IFD offsets are usually recorded in
       the file	as offsets relative to the beginning of	the TIFF header	(which
       is  offset  from	 the beginning of the file in JPEG APP1	files) but are
       adjusted	by exifprobe to	show offset from the beginning	of  the	 file.
       If  it  is  important  to see the recorded value, the -er option	may be
       used to print the recorded value	in parentheses,	following the adjusted
       file offset.

   Report Format
       The  report format (-R) displays	all sections and segments of the image
       file, including start and end of	sections, but eliminates much  of  the
       "cruft" of the structural format	by eliminating address/offset informa-
       tion and	much of	the `internal' information from	the TIFF IFD (tag num-
       ber,  type  and	count).	 Offset	values are printed inline with the tag
       name.  The output is indented to	show the logical structure of the  im-
       age  file,  but is much less difficult to view than the structural for-

   List	format
       The list	format (-L) suppresses structural  information,	 writing  only
       content	in the format tagname =	value or tagname = value = "what value
       means". For non-tagged file formats, the	tagname	will be	replaced by  a
       fixed  identifier  for  the  item.  In LIST format, "long" tagnames are
       used, which include the names of	all parent sections of the section  in
       which  the  data	 is found.  Long tagnames can be toggled off, although
       this is unwise if the file contains multiple image sections.

       The "value" of tags or items which represent an offset to a  subsection
       or image	are printed in list format as "@offset:length".

       The  List  format is used by the	auxilliary script exifgrep, which per-
       mits selective extraction of information	e.g. for photo galleries,  and
       output in (almost) "shell variable" format.

   Custom Formats
       The  -Z	option	"zeroes"  all option flags (except the longnames modi-
       fier), after which the lower-case options may be	used  to  set  desired
       options.	  The lower-case options are `toggles',	which may also be used
       to turn off items in the	pre-defined formats.

       As an example, the command:

	   exifprobe -Z	-et somefile.tif

       may be used to list just	the TIFF and Exif  tags,  without  values  (or
       anything	else) in "long name" format.

	    exifprobe -eNnT somefile.tif

       will  print in structural format, suppressing output of hex and decimal
       tag numbers, and	tag type and count.

       The "zero-level"	output still reports the file data and	image  summary
       as described above.

       The  environment	variable EXIFPROBE_OPTIONS may be set to any valid op-
       tion string, which will be evaluated before command line	options. E.g.

       export EXIFPROBE_OPTIONS='-L -c'

       will make list format the default  output  format,  and	re-enable  the
       color sequences turned off by -L.

       Options	are evaluated from left	to right, so -Z	should be given	first,
       while -D	(decimal only) or -X (hex only)	should be given	last.

       -S	 Structure mode: (default) almost  everything;	offset	values
		 not inline

       -R	 Report	 mode:	like structural, but only tagnames and decimal
		 values, indented, inline

       -L	 List mode: print only tags and	values (including  interpreted
		 values); no section info; no color

       -Z	 turn  off  (zero)  all	optional output. Prints	only filename,
		 filetype, filesize, image summary, and	file format.

       -c	 toggle	use of ANSI color control sequences to emphasize  EXIF
		 sections.   (default  'on'  except list mode, unless compiled
		 with no color support)

       -a	 toggle	printing of addresses (file offsets) in	hex and	 deci-

       -I	 three-way toggle indent (after	address	-> before -> none)

       -o	 toggle	"inline" print of offset IFD values

       -p[items] toggle	print identifiers for:

		 s   - sections	(IFDs, APPn)

		 g   - segments	(JPEG segments)

		 a   - JPEG APP0...APPn	entries

		 l   -	long names (dot-separated list of parent sections pre-
		     ceding item name)

		 e   - entries.	Includes tag names, numbers, types, values.

		 m   - print MakerNote scheme description

		 M   - watch debug of MakerNote	scheme detection

       -e[items] toggle	print IFD entry	items:

		 t   - tagname

		 n   - tag number in decimal

		 N   - tag number in hex

		 T   - entry type and count

		 v   - value in	decimal

		 V   - value in	hex

		 o   - file offset to value in decimal

		 O   - file offset to value in hex

		 r   - relative	(unadjusted) offset in decimal

		 R   - also print "raw"	values where normal  values  are  com-
		     puted  (e.g.  rational  values,  or some MakerNote	values
		     where APEX	values must be computed	from a raw value).

		 A   - print ALL elements of multiple-value tags

		 a   - ascii "ignore length" (stop at first null)

       -D	 limit all enabled  numerical  values  to  decimal  only  (ad-
		 dresses, tag numbers, offsets,	values)

       -X	 limit	all  enabled  numerical	values to hex only (addresses,
		 tag numbers, offsets, values)

       -U[len|a] dump len (or all) bytes of UNDEFINED data found in TIFF  IFDS
		 in  hex/ascii	form (but only if the structure	of the data is
		 not known)

       -M[len|a] dump  len  (or	 all)  bytes  of  unrecognized	MakerNotes  in
		 hex/ascii  form (but only if the structure of the data	is not

       -A[len|a] dump len (or all) bytes of unrecognized JPEG APP segments  in
		 hex/ascii  form (but only if the structure of the data	is not

       -B[len|a] dump len (or all) bytes of binary image data or  failed  JPEG
		 image data

		 print a list of camera	makes/models matching make or model as
		 substrings.  `+' by itself prints everything

       -O start_offset
		 start processing at file offset start_offset

       -n	 print filename	at beginning of	each line  of  output  (useful
		 when grepping multiple	files in LIST mode)

       -N noteversion
		 force	use of note version noteversion	when interpreting Mak-
		 erNotes.  Useful only if you know what	you're doing.

       -m make	 Force the makernote code to interpret the note	 according  to
		 the make given, rather	than that contained in the file.

       -l model	 force	the  makernote code to interpret the note according to
		 the model given, rather than that contained in	the file.

       -t	 This option has effect	only if	set in EXIFPROBE_OPTIONS.   If
		 set  when  command line options are processed,	color  will be
		 be off	by default if the output is not	to a tty.  Any command
		 line option which toggles or sets color (e.g. "-R") will turn
		 color back on.

       -u	 Print "raw" Unicode data.  Normally 16	bit data is printed as
		 though	 the  high  byte  is  zero  (which is often the	case).
		 Writing the nulls would annoy most ascii terminal devices, so
		 the  default is more hospitable.  The -u option forces	print-
		 ing of	the full value.

       -h	 print a help message

       -V	 print program version and copyright

       The TIFF6 specification:
       The Exif	2.2 specification:
       The JFIF	specification:
       The TIFF/EP specification:
       The CIFF	specification
       The X3F public specification
       The JPEG2000 public draft (outdated)

       Most diagnostics	are printed "inline" to	stdout,	in red if color	is en-
       abled, and the program attempts to proceed.

       Interpretation of MakerNote data	for specific cameras is	incomplete and
       probably	always will be.	 The X3F specification is incomplete, and  the
       final  JPEG2000/JP2  specification is not freely	available; support for
       these formats is	therefore not complete,	and may	not be entirely	 accu-

       The RAF file format support is preliminary (there is no published spec-

       Floating	point values read from the file	are expected  to  be  in  IEEE
       format (or at least, native format); i.e. no conversions	are attempted.

       ANSI  color sequence support should use termcap/terminfo	facilities; it
       does not.

       Duane H.	Hesser

				     LOCAL			  EXIFPROBE(1)


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