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diff --git a/upstream/fedora-40/man1/pnmtojbig.1 b/upstream/fedora-40/man1/pnmtojbig.1 new file mode 100644 index 00000000..733c97fd --- /dev/null +++ b/upstream/fedora-40/man1/pnmtojbig.1 @@ -0,0 +1,293 @@ +\ +.\" 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 "Pnmtojbig User Manual" 0 "28 July 2020" "netpbm documentation" + +.SH NAME + +pnmtojbig - PNM to JBIG file converter + +.UN synopsis +.SH SYNOPSIS + +\fBpnmtojbig\fP + +[\fIoptions\fP] +[\fIinput-file\fP [\fIoutput-file\fP]] + +.UN description +.SH DESCRIPTION +.PP +This program is part of +.BR "Netpbm" (1)\c +\&. +.PP +\fBpnmtojbig\fP reads a PBM or PGM image, compresses it, and +outputs the image as a JBIG bi-level image entity (BIE) file. +.PP +JBIG is a highly effective lossless compression algorithm for +bi-level images (one bit per pixel), which is particularly suitable +for scanned document pages. +.PP +A JBIG encoded image can be stored in several resolutions +(progressive mode). These resolution layers can be stored all in one +single BIE or they can be stored in several separate BIE files. All +resolution layers except the lowest one are stored merely as +differences to the next lower resolution layer, because this requires +less space than encoding the full image completely every time. Each +resolution layer has twice the number of horizontal and vertical +pixels than the next lower layer. JBIG files can also store several +bits per pixel as separate bitmap planes, and \fBpnmtojbig\fP +can read a PGM file and transform it into a multi-bitplane BIE. + +.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 +\&), \fBpnmtojbig\fP recognizes the following +command line options: + + + +.TP +\fB-q\fP +Encode the image in one single resolution layer (sequential +mode). This is usually the most efficient compression method. By +default, the number of resolution layers is chosen automatically such +that the lowest layer image is not larger than 640 \(mu 480 pixels. + +.TP +\fB-x\fP \fInumber\fP +Specify the maximal horizontal size of the lowest resolution +layer. The default is 640 pixels. + +.TP +\fB-y\fP \fInumber\fP +Specify the maximal vertical size of the lowest resolution layer. +The default is 480 pixels. + +.TP +\fB-l\fP \fInumber\fP +Select the lowest resolution layer that will be written to the +BIE. It is possible to store the various resolution layers of a JBIG +image in progressive mode into different BIEs. Options \fB-l\fP and +\fB-h\fP allow you to select the resolution-layer interval that will +appear in the created BIE. The lowest resolution layer has number 0 +and this is also the default value. By default, \fBpnmtojbig\fP +writes all layers. + +.TP +\fB-h\fP \fInumber\fP +Select the highest resolution layer that will be written to the +BIE. By default, \fBpnmtojbig\fP writes all layers. See also option +\fB-l\fP. + +.TP +\fB-b\fP +Use binary values instead of Gray code words in order to encode +pixel values in multiple bitplanes. This option has only an effect if +the input is a PGM file and if more than one bitplane is +produced. Note that the decoder has to make the same selection but +cannot determine from the BIE, whether Gray or binary code words were +used by the encoder. + +.TP +\fB-d\fP \fInumber\fP +Specify the total number of differential resolution layers into +which the input image will be split in addition to the lowest layer. +Each additional layer reduces the size of layer 0 by 50 %. This +option overrides options \fB-x\fP and \fB-y\fP, which are usually a +more comfortable way of selecting the number of resolution layers. + +.TP +\fB-s\fP \fInumber\fP +The JBIG algorithm splits each image into a number of horizontal +stripes. This option specifies that each stripe shall have +\fInumber\fP lines in layer 0. The default value is selected so that +approximately 35 stripes will be used for the whole image. + +.TP +\fB-m\fP \fInumber\fP +Select the maximum horizontal offset of the adaptive template pixel. The +JBIG encoder uses a number of neighbour pixels in order to get statistical a +priori knowledge of the probability, whether the next pixel will be black or +white. One single pixel out of this template of context neighbor pixels can +be moved around. Especially for dithered images it can be a significant +advantage to have one neighbor pixel which has a distance large enough to +cover the period of a dither function. By default, the adaptive template +pixel can be moved up to 8 pixels away. This encoder go up to 23 pixels, +however as decoders are only required to handle at least a distance of 16 +pixels by the standard, no higher value than 16 for +\fInumber\fP is recommended in order to maintain interoperability +with other JBIG implementations. The maximal vertical offset of the +adaptive template pixel is always zero. + +.TP +\fB-t\fP \fInumber\fP +Encode only the specified number of most significant bit planes. +This option allows to reduce the depth of an input PGM file if not all +bits per pixel are needed in the output. + +.TP +\fB-o\fP \fInumber\fP +JBIG separates an image into several horizontal stripes, +resolution layers and planes, were each plane contains one bit per +pixel. One single stripe in one plane and layer is encoded as a data +unit called stripe data entity (SDE) inside the BIE. There are 12 +different possible orders in which the SDEs can be stored inside the +BIE and \fInumber\fP selects which one shall be used. The order of +the SDEs is only relevant for applications that want to decode a JBIG +file which has not yet completely arrived from e.g. a slow network +connection. For instance some applications prefer that the outermost +of the three loops (stripes, layers, planes) is over all layers so +that all data of the lowest resolution layer is transmitted first. +.sp +The following values for \fInumber\fP select these loop +arrangements for writing the SDEs (outermost loop first): + + +.TP +0 +planes, layers, stripes + +.TP +2 +layers, planes, stripes + +.TP +3 +layers, stripes, planes + +.TP +4 +stripes, planes, layers + +.TP +5 +planes, stripes, layers + +.TP +6 +stripes, layers, planes + + +.sp +All loops count starting with zero, however by adding 8 to the +above order code, the layer loop can be reversed so that it counts +down to zero and then higher resolution layers will be stored before +lower layers. Default order is 3 which writes at first all planes of +the first stripe and then completes layer 0 before continuing with the +next layer and so on. + +.TP +\fB-p\fP \fInumber\fP +This option allows you to activate or deactivate various optional +algorithms defined in the JBIG standard. Just add the numbers of the +following options which you want to activate in order to get the +\fInumber\fP value: + + +.TP +4 +deterministic prediction (DPON) + +.TP +8 +typical prediction (TPBON) + +.TP +16 +diff. layer typical prediction (TPDON) + +.TP +64 +layer 0 two-line template (LRLTWO) + + +.sp +Except for special applications (like communication with JBIG +subset implementations) and for debugging purposes you will normally +not want to change anything here. The default is 28, which provides +the best compression result. + +.TP +\fB-c\fP +The adaptive template pixel movement is determined as suggested in +annex C of the standard. By default the template change takes place +directly in the next line which is most effective. However a few +conformance test examples in the standard require the adaptive +template change to be delayed until the first line of the next stripe. +This option selects this special behavior, which is normally not +required except in order to pass some conformance test suite. + +.TP +\fB-v\fP +After \fBpnmtojbig\fP creates the BIE, it lists a few technical +details of the created file (verbose mode). + + + +.UN formats +.SH FORMATS +.PP +Most of the format \fBpnmtojbig\fP creates is defined by the +JBIG standard. +.PP +The standard, however, does not specify which values in the BIE mean +white and which mean black. It contains a recommendation that for a +single plane image zero mean background and one mean foreground, but +the Netpbm formats have no concept of foreground and background. And +the standard says nothing about values for multiple plane BIEs. +.PP +\fBpnmtojbig\fP follows Markus Kuhn's implementation of the +standard in the \fBpbmtojbg\fP program that comes with his +JBIG library: If the BIE is a single plane BIE, zero means +white and one means black. If it is a multiple plane BIE, zero means +black and the maximal value is white. + +.UN standards +.SH STANDARDS +.PP +This program implements the JBIG image coding algorithm as +specified in ISO/IEC 11544:1993 and ITU-T T.82(1993). + +.UN author +.SH AUTHOR + +\fBpnmtojbig\fP is based on the JBIG library by Markus Kuhn, part of +his \fBJBIG-KIT\fP package. The \fBpbmtojbg\fP program is part of +the \fIJBIG-KIT\fP package. The most recent version of that library +and tools set is freely available on the Internet from anonymous ftp +server +.UR ftp://ftp.informatik.uni-erlangen.de +ftp.informatik.uni-erlangen.de +.UE +\& +in directory pub/doc/ISO/JBIG/. +.PP +\fBpnmtojbig\fP is part of the Netpbm package of graphics tools. + +.UN seealso +.SH SEE ALSO +.BR "pnm" (1)\c +\&, +.BR "jbigtopnm" (1)\c +\& + +.UN license +.SH LICENSE +.PP +There was at one time concern about the need for patent licenses to +use \fBpnmtojbig\fP, but any relevant patents expired by 2012. +.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/pnmtojbig.html +.PP
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