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diff --git a/upstream/mageia-cauldron/man1/pamtilt.1 b/upstream/mageia-cauldron/man1/pamtilt.1 new file mode 100644 index 00000000..07b8c762 --- /dev/null +++ b/upstream/mageia-cauldron/man1/pamtilt.1 @@ -0,0 +1,181 @@ +\ +.\" This man page was generated by the Netpbm tool 'makeman' from HTML source. +.\" Do not hand-hack it! If you have bug fixes or improvements, please find +.\" the corresponding HTML page on the Netpbm website, generate a patch +.\" against that, and send it to the Netpbm maintainer. +.TH "Pamtilt User Manual" 0 "28 August 2005" "netpbm documentation" + +.SH NAME +pamtilt - print the tilt angle of a PGM file + +.UN synopsis +.SH SYNOPSIS + +\fBpamtilt\fP +[\fB-angle=\fP\fImaxangle\fP] +[\fB-fast\fP] +[\fB-quality=\fP\fIq\fP] +[\fB-hstep=\fP\fIn\fP] +[\fB-vstep=\fP\fIn\fP] +[\fB-dstep=\fP\fIn\fP] +[\fB-astep=\fP\fIn\fP] +[\fB-verbose\fP] +[\fIpgmfile\fP] + +.UN examples +.SH EXAMPLES + +.nf +\f(CW + scanimage --mode Gray --resolution 300 >crooked.pgm + pnmrotate -b white `pamtilt crooked.pgm` crooked.pgm >straight.pgm +\fP + (then crop, threshold, etc.) + +.fi + +.UN description +.SH DESCRIPTION +.PP +This program is part of +.BR "Netpbm" (1)\c +\&. +.PP +\fBpamtilt\fP tries to find the correct angle for untilting +(de-skewing) a scanned text document. The output is a single +floating-point number (the angle in degrees) for use as the argument +to pnmrotate. +.PP +"Document skew" is the name given to what happens when +you feed a page into an image scanner at an angle: the resulting image +is tilted. \fBpamtilt\fP aims to help correct that. +.PP +\fBpamtilt\fP makes three iterations at successively finer +increments, testing prospective rotation angles to find the best one. +\fBpamtilt\fP works best for straightening images with strong +horizontal lines and does poorly with arbitrary photos. If +\fBpamtilt\fP has no confidence in its results, it prints the special +value 00.00; you can check for this or just pass it as a legal +argument to pnmrotate. +.PP +\fBpamtilt\fP operates on the first plane of the input image, +which is either PNM or PAM, and ignores any other planes. Ordinarily, +the input is PGM or GRAYSCALE PAM, so there is only one plane. +.PP +\fBpamtilt\fP works on bilevel (PBM, BLACKANDWHITE PAM) images as +well as grayscale, but you will minimize artifacts if you scan and +rotate in grayscale before you apply a threshold to make a bilevel +image. + +.UN options +.SH OPTIONS +.PP +In addition to the options common to all programs based on libnetpbm +(most notably \fB-quiet\fP, see +.UR index.html#commonoptions + Common Options +.UE +\&), \fBpamtilt\fP recognizes the following +command line options: + + + +.TP +\fB-angle=\fP\fImaxangle\fP +Assume a maximum tilt angle of \fImaxangle\fP (measured in degrees). +The default value is sufficient for most images, even those scanned +somewhat carelessly. +.sp +The default is 10.0. + +.TP +\fB-fast\fP +Skip the third iteration for speed at the expense of accuracy. + +.TP +\fB-verbose\fP +Show on Standard Error the measurements computed at each tested angle. + + +.PP +Here are some other options you can use to tune the operation of +\fBpamtilt\fP but they're seldom needed. The default values +accommodate a wide variety of input documents. + + +.TP + +\fB-quality=\fP\fIq\fP +Require a signal-to-noise ratio of a least \fIq\fP on the first +iteration to report a valid result. Larger values reduce the chances +of obtaining a bogus result at the risk of obtaining no result at all. +.sp +The default is 1.0. + +.TP +\fB-hstep=\fP\fIn\fP +Set the horizontal increment to check every \fIn\fPth column. This +value affects both run time and memory requirements. +.sp +The default is 11. + +.TP +\fB-vstep=\fP\fIn\fP +Set the vertical increment to check every nth row. Larger values +usually work, reducing run time, but they increase the risk of +incorrect results. +.sp +The default is 5. + +.TP +\fB-dstep=\fP\fIn\fP +Set the vertical distance used when checking pixels in a column. The +default is intended to minimize the effect of noise along a horizontal +boundary. +.sp +The default is 2. + +.TP +\fB-astep=\fP\fIn\fP +Set the angle increment of the first iteration, in degrees. +.sp +The default is 1.0. + + + + +.UN references +.SH REFERENCES +.PP +\fBpamtilt\fP implements a somewhat simplified algorithm inspired +by: "Measuring Document Image Skew and Orientation", by Bloomberg, +Kopec, and Dasari. In SPIE Volume 2422, Document Recognition II, +pages 302-316, February 1995. + +.UN seealso +.SH SEE ALSO + + +.IP \(bu + +.BR "\fBpnmrotate\fP" (1)\c +\& +.IP \(bu + +.BR "pgm" (1)\c +\& + + +.UN history +.SH HISTORY +.PP +\fBpamtilt\fP was new in Netpbm 10.30 (October 2005). +.PP +Gregg Townsend wrote it and sent it to Bryan Henderson in August +2005. Bryan recoded it to fit Netpbm conventions. +.SH DOCUMENT SOURCE +This manual page was generated by the Netpbm tool 'makeman' from HTML +source. The master documentation is at +.IP +.B http://netpbm.sourceforge.net/doc/pamtilt.html +.PP
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