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annotate CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/share/man/man1/wrjpgcom.1 @ 68:5028fdace37b

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planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
author jpayne
date Tue, 18 Mar 2025 16:23:26 -0400
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jpayne@68 1 .TH WRJPGCOM 1 "15 June 1995"
jpayne@68 2 .SH NAME
jpayne@68 3 wrjpgcom \- insert text comments into a JPEG file
jpayne@68 4 .SH SYNOPSIS
jpayne@68 5 .B wrjpgcom
jpayne@68 6 [
jpayne@68 7 .B \-replace
jpayne@68 8 ]
jpayne@68 9 [
jpayne@68 10 .BI \-comment " text"
jpayne@68 11 ]
jpayne@68 12 [
jpayne@68 13 .BI \-cfile " name"
jpayne@68 14 ]
jpayne@68 15 [
jpayne@68 16 .I filename
jpayne@68 17 ]
jpayne@68 18 .LP
jpayne@68 19 .SH DESCRIPTION
jpayne@68 20 .LP
jpayne@68 21 .B wrjpgcom
jpayne@68 22 reads the named JPEG/JFIF file, or the standard input if no file is named,
jpayne@68 23 and generates a new JPEG/JFIF file on standard output. A comment block is
jpayne@68 24 added to the file.
jpayne@68 25 .PP
jpayne@68 26 The JPEG standard allows "comment" (COM) blocks to occur within a JPEG file.
jpayne@68 27 Although the standard doesn't actually define what COM blocks are for, they
jpayne@68 28 are widely used to hold user-supplied text strings. This lets you add
jpayne@68 29 annotations, titles, index terms, etc to your JPEG files, and later retrieve
jpayne@68 30 them as text. COM blocks do not interfere with the image stored in the JPEG
jpayne@68 31 file. The maximum size of a COM block is 64K, but you can have as many of
jpayne@68 32 them as you like in one JPEG file.
jpayne@68 33 .PP
jpayne@68 34 .B wrjpgcom
jpayne@68 35 adds a COM block, containing text you provide, to a JPEG file.
jpayne@68 36 Ordinarily, the COM block is added after any existing COM blocks; but you
jpayne@68 37 can delete the old COM blocks if you wish.
jpayne@68 38 .SH OPTIONS
jpayne@68 39 Switch names may be abbreviated, and are not case sensitive.
jpayne@68 40 .TP
jpayne@68 41 .B \-replace
jpayne@68 42 Delete any existing COM blocks from the file.
jpayne@68 43 .TP
jpayne@68 44 .BI \-comment " text"
jpayne@68 45 Supply text for new COM block on command line.
jpayne@68 46 .TP
jpayne@68 47 .BI \-cfile " name"
jpayne@68 48 Read text for new COM block from named file.
jpayne@68 49 .PP
jpayne@68 50 If you have only one line of comment text to add, you can provide it on the
jpayne@68 51 command line with
jpayne@68 52 .BR \-comment .
jpayne@68 53 The comment text must be surrounded with quotes so that it is treated as a
jpayne@68 54 single argument. Longer comments can be read from a text file.
jpayne@68 55 .PP
jpayne@68 56 If you give neither
jpayne@68 57 .B \-comment
jpayne@68 58 nor
jpayne@68 59 .BR \-cfile ,
jpayne@68 60 then
jpayne@68 61 .B wrjpgcom
jpayne@68 62 will read the comment text from standard input. (In this case an input image
jpayne@68 63 file name MUST be supplied, so that the source JPEG file comes from somewhere
jpayne@68 64 else.) You can enter multiple lines, up to 64KB worth. Type an end-of-file
jpayne@68 65 indicator (usually control-D) to terminate the comment text entry.
jpayne@68 66 .PP
jpayne@68 67 .B wrjpgcom
jpayne@68 68 will not add a COM block if the provided comment string is empty. Therefore
jpayne@68 69 \fB\-replace \-comment ""\fR can be used to delete all COM blocks from a file.
jpayne@68 70 .SH EXAMPLES
jpayne@68 71 .LP
jpayne@68 72 Add a short comment to in.jpg, producing out.jpg:
jpayne@68 73 .IP
jpayne@68 74 .B wrjpgcom \-c
jpayne@68 75 \fI"View of my back yard" in.jpg
jpayne@68 76 .B >
jpayne@68 77 .I out.jpg
jpayne@68 78 .PP
jpayne@68 79 Attach a long comment previously stored in comment.txt:
jpayne@68 80 .IP
jpayne@68 81 .B wrjpgcom
jpayne@68 82 .I in.jpg
jpayne@68 83 .B <
jpayne@68 84 .I comment.txt
jpayne@68 85 .B >
jpayne@68 86 .I out.jpg
jpayne@68 87 .PP
jpayne@68 88 or equivalently
jpayne@68 89 .IP
jpayne@68 90 .B wrjpgcom
jpayne@68 91 .B -cfile
jpayne@68 92 .I comment.txt
jpayne@68 93 .B <
jpayne@68 94 .I in.jpg
jpayne@68 95 .B >
jpayne@68 96 .I out.jpg
jpayne@68 97 .SH SEE ALSO
jpayne@68 98 .BR cjpeg (1),
jpayne@68 99 .BR djpeg (1),
jpayne@68 100 .BR jpegtran (1),
jpayne@68 101 .BR rdjpgcom (1)
jpayne@68 102 .SH AUTHOR
jpayne@68 103 Independent JPEG Group