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diff --git a/upstream/opensuse-leap-15-6/man1/pamtopng.1 b/upstream/opensuse-leap-15-6/man1/pamtopng.1 new file mode 100644 index 00000000..7b6cfacd --- /dev/null +++ b/upstream/opensuse-leap-15-6/man1/pamtopng.1 @@ -0,0 +1,384 @@ +\ +.\" 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 "Pamtopng User Manual" 0 "12 March 2017" "netpbm documentation" + +.SH NAME +pamtopng - convert a Netpbm image to PNG + +.UN synopsis +.SH SYNOPSIS + +\fBpamtopng\fP +[\fB-verbose\fP] +[\fB-transparent=\fP\fIcolor\fP] +[\fB-background=\fP\fIcolor\fP] +[\fB-gamma=\fP\fIvalue\fP] +[\fB-chroma='\fP\fIwx\fP \fIwy\fP + \fIrx\fP \fIry\fP \fIgx\fP \fIgy\fP \fIbx\fP \fIby\fP\fB'\fP] +[\fB-srgbintent=\fP\fIintent\fP] +[\fB-time=\fP[\fIyy\fP]\fIyy\fP\fB-\fP\fImm\fP\fB-\fP\fIdd\fP + \fIhh\fP\fB:\fP\fImm\fP\fB:\fP\fIss\fP] +[\fB-text=\fP\fIfile\fP] +[\fB-ztxt=\fP\fIfile\fP] +[\fB-itxt=\fP\fIfile\fP] +[\fIpnmfile\fP] + +.SH OPTION USAGE +.PP +Minimum unique abbreviation of option is acceptable. You may use double +hyphens instead of a single hyphen to denote options. You may use white space +in place of the equals sign to separate an option name from its value. + +.UN description +.SH DESCRIPTION +.PP +This program is part of +.BR "Netpbm" (1)\c +\&. +.PP +\fBpamtopng\fP reads a Netpbm image as input and produces a PNG image as +output. +.PP +Color component values in PNG files are either 8 or 16 bits wide, so where +necessary \fBpamtopng\fP scales colors to have a maxval of 255 or 65535. +In that case, it will add an sBIT chunk to indicated the original bit-depth. +.PP +\fBpamtopng\fP works only on images with maxval 1, 3, 15, 255, or 65535. +You can use \fBpamdepth\fP to convert an image with some other maxval to one +of these. +.PP +\fBpamtopng\fP produces a color PNG from a color PAM, even if the +only colors in the image are shades of gray. To create a graycale PNG, +from such an image (which might be slightly smaller), you can use other +Netpbm programs to convert the input to grayscale. + +.UN pnmtopng +.SS Alternative: \fBpnmtopng\fP +.PP +Netpbm contains another program for generating PNG images: \fBpnmtopng\fP. +\fBpnmtopng\fP is a much older program - it is in fact the first program in +the world that could generate a PNG. \fBpnmtopng\fP is a complex, +feature-laden program. It lets you control various arcane aspects of the +conversion and create PNGs with various arcane features. It does various +transformations on the image to create the greatest compression possible, to a +degree that probably doesn't make any difference in the modern world. +.PP +The main advantage \fBpamtopng\fP has over \fBpnmtopng\fP is that the +former can use the transparency channel of a PAM image to generate the +transparency information in the PNG. In contrast, handling of the alpha +channel is very cumbersome with \fBpnmotpng\fP. +.PP +One difference that \fIdoes not\fP exist, that some people might +incorrectly infer from the names is the possible input formats. Both programs +can take PBM, PGM, PPM, and PAM input. +.PP +Because \fBpnmtopng\fP has been around virtually forever, programs and +procedures that use it are more portable than those that use \fBpamtopng\fP. +Its age and popularity also probably make it have fewer bugs. +.PP +\fBpamtopng\fP does not have any way to do what the following do in +\fBpnmtopng\fP: + + +.IP \(bu +\fB-palette\fP +.IP \(bu +\fB-history\fP +.IP \(bu +\fB-filter\fP +.IP \(bu +\fB-size\fP +.IP \(bu +\fB-paeth\fP +.IP \(bu +\fB-hist\fP +.IP \(bu +\fB-nofilter\fP +.IP \(bu +\fB-sub\fP +.IP \(bu +\fB-up\fP +.IP \(bu +\fB-avg\fP +.IP \(bu +\fB-force\fP +.IP \(bu +\fB-libversion\fP +.IP \(bu +\fB-compression\fP +.IP \(bu +\fB-comp_\fP\fIxxx\fP + +.PP +These are some of the other functions of \fBpnmtopng\fP that +\fBpamtopng\fP lacks: + + +.IP \(bu +When you specify a transparent or background color that is not in the +image, \fBpnmtopng\fP can optionally choose the closest one that is in the +image. \fBpamtopng\fP always uses the exact color you specify. + +.PP +Features that exist in both programs are controlled by largely the same +command syntax. But there are these differences: + + +.IP \(bu +\fBpnmtopng\fP's \fB-rgb\fP option is \fB-chroma\fP in \fBpamtopng\fP. +\fB-chroma\fP is a better name, and in fact was the name that \fBpnmtopng\fP +used originally, but we had to change it when we had to change the syntax +of the option value to conform to the rest of Netpbm. + +.IP \(bu +\fBpnmtopng\fP's \fB-modtime\fP option is \fB-time\fP in +\fBpamtopng\fP. The origin of \fB-modtime\fP is analogous to that of +\fB-rgb\fP. + + + + +.UN options +.SH OPTIONS + + + +.TP +\fB-transparent=\fP\fIcolor\fP +\fBpamtopng\fP marks the specified color as transparent in the PNG image. +.sp +Specify the color (\fIcolor\fP) as described for +the +.UR libppm.html#colorname +argument of the \fBppm_parsecolor()\fP library routine +.UE +\&. E.g. \fBred\fP or \fBrgb:ff/00/0d\fP. + +.TP +\fB-background=\fP\fIcolor\fP +This causes \fBpamtopng\fP to create a background color chunk in the PNG +output which can be used for subsequent transparency channel or transparent +color conversions. Specify \fIcolor\fP the same as for \fB-transparent\fP. + +.TP +\fB-gamma=\fP\fIvalue\fP +This causes \fBpnmtopng\fP to create a gAMA chunk. This information +helps describe how the color values in the PNG must be interpreted. Without +the gAMA chunk, whatever interprets the PNG must get this information +separately (or just assume something standard). If your input is a true PPM +or PGM image, you should specify \fB-gamma=.45\fP. But sometimes people +generate images which are ostensibly PPM except the image uses a different +gamma transfer function than the one specified for PPM. A common case of this +is when the image is created by simple hardware that doesn't have digital +computational ability. Also, some simple programs that generate images from +scratch do it with a gamma transfer in which the gamma value is 1.0. + +.TP +\fB-chroma=\fP\fIchroma_list\fP +This option specifies how red, green, and blue component values +of a pixel specify a particular color, by telling the chromaticities +of those 3 primary illuminants and of white (i.e. full strength of +all three). +.sp +The \fIchroma_list\fP value is a blank-separated list of 8 floating +point decimal numbers. The CIE-1931 X and Y chromaticities (in that +order) of each of white, red, green, and blue, in that order. +.sp +This information goes into the PNG's cHRM chunk. +.sp +In a shell command, make sure you use quotation marks so that the +blanks in \fIchroma_list\fP don't make the shell see multiple command +arguments. + +.TP +\fB-srgbintent=\fP\fIintent\fP +This asserts that the input is a pseudo-Netpbm image that uses an +sRGB color space (unlike true Netpbm) and indicates how you intend for the +colors to be rendered. It causes \fBpamtopng\fP to include an sRGB chunk +in the PNG image that specifies that intent, so see the PNG documentation for +more information on what this really means. +.sp +\fIintent\fP is one of: + + +.IP \(bu +\fBperceptual\fP +.IP \(bu +\fBrelativecolorimetric\fP +.IP \(bu +\fBsaturation\fP +.IP \(bu +\fBabsolutecolorimetric\fP + + +.TP +\fB-text=\fP\fIfilename\fP +This option lets you include arbitrary text strings in the PNG output, as tEXt +chunks. + +\fIfilename\fP is the name of a file that contains your text strings. +.sp +The output contains a distinct tEXt chunk for each entry in the file. +.sp +Here is an example of a text string file: + +.nf + Title PNG file + Author John Doe + Description how to include a text chunk + PNG file + "Creation Date" 2015-may-11 + Software pamtopng +.fi +.sp +The file is divided into entries, each entry comprising consecutive lines +of text. The first line of an entry starts in the first column (i.e. the +first column is not white space) and every other line has white space in the +first column. The first entry starts in the first line, so it is not valid +for the first line of the file to have white space in its first column. +.sp +The first word in an entry is the key of the text string +(e.g. 'Title'). It begins in column one of the line and continues +up to, but not including, the first delimiter character or the end of the +line, whichever is first. You can enclose the key in double quotes in +which case the key can consists of multiple words. The quotes are not +part of the key. The text string per se begins after the key and any +delimiter characters after it, plus the text in subsequent continuation lines. +.sp +There is no limit on the length of a file line or entry or key or text +string. There is no limit on the number of entries. + +.TP +\fB-ztxt=\fP\fIfilename\fP +The same as \fB-text\fP, except the text string is compressed in the +PNG output. \fBpnmtopng\fP uses zTXt chunks instead of a tEXt chunks. + +.TP +\fB-itxt=\fP\fIfilename\fP +Similar to \fB-text\fP, but the text strings can be in a language other +than English. The PNG image indicates what language that is and includes the +text string key both in English and that language. \fBpnmtopng\fP uses +iTXt chunks instead of tEXt chunks. +.sp +For each record, you must specify the language and give the key both in +English and in the text string language. +.sp +Example: + +.nf + Language nl-NL Taal nl-NL + Title nl-NL Titel PNG file + Author nl-NL Auteur Pietje Puk + Description nl-NL Omschrijving Tekst in het Nederlands. +.fi +.sp +The language specification is based on the ISO 639-1 standard, see +http://en.wikipedia.org/wiki/List_of_ISO_639-1_codes for the valid codes. +The format is either a two character "nl" or an extended code like "en-US". + +.TP +\fB-time='\fP[\fIyy\fP]\fIyy-mm-dd hh:mm:ss\fP\fB'\fP +This option allows you to specify the modification time value to be placed +in the PNG output. You can specify the year parameter either as a two or four +digit value. + +.TP +\fB-verbose\fP +This causes the program to display various facts about the conversion. + + + + +.UN seealso +.SH SEE ALSO +.BR "pngtopam" (1)\c +\&, +.BR "pnmtopng" (1)\c +\&, +.BR "pam" (5)\c +\&, +.BR "pnm" (5)\c +\& +.PP +For information on the PNG format, see +.UR http://www.w3.org/TR/PNG/ +http://www.w3.org/TR/PNG/ +.UE +\&, +.UR http://libpng.org/pub/png/ +http://libpng.org/pub/png/ +.UE +\&, +.UR http://en.wikipedia.org/wiki/List_of_ISO_639-1_codes +http://en.wikipedia.org/wiki/List_of_ISO_639-1_codes +.UE +\& and +.UR http://schaik.com/png/ +http://schaik.com/png/ +.UE +\&. + +.UN history +.SH HISTORY +.PP +\fBpamtopng\fP was new in Netpbm 10.70 (June 2015). +.PP +Before \fBpamtopng\fP, the two ways to create PNG images with Netpbm +were \fBpnmtopng\fP and \fBpamrgbatopng\fP. The history of the former is +discussed above. The latter was added to Netpbm in 2005 as a cheap way to +fill a significant need that \fBpnmtopng\fP did not: the ability to turn the +alpha channel in a PAM image into the alpha channel in a PNG image. +.PP +Handling of the alpha channel with \fBpnmtopng\fP is very cumbersome (as +was dealing with alpha channels in general before the introduction of the PAM +format). \fBpamrgbatopng\fP could do what people wanted with the alpha +channel, but nothing else. It was a very small program with literally no +command line options. +.PP +The goal in those days was eventually to expand \fBpnmtopng\fP to do the +PAM alpha channel thing, rename it to \fBpamtopng\fP, and retire +\fBpamrgbatopng\fP. But \fBpnmtopng\fP is such a complex program, because +of its dizzying array of features and its need for backward compatibility, +that adding that one capability to it was a daunting task and for ten years +nobody attempted it. +.PP +In 2015, one of the authors of the original \fBpnmtopng\fP (from before it +was even part of Netpbm -- a program that shared essentially no lines of code +with \fBpnmtopng\fP of 2015) decided to go in a different direction. While +many features of \fBpnmtopng\fP were pretty important and easy to implement, +many others were probably of no use in the modern world or at least not +important enough to justify the complexity they lent to the code. (The +features thought to be outdated were ones that were intended to make the PNG +output slightly smaller - something considerably less important with the +declining cost of computer resources). +.PP +And there was an opportunity to drop those features: We could use the new +name 'pamtopng' for a new program, keep the existing program under +the name 'pnmtopng', and avoid most backward compatibility trouble. +.PP +Therefore, Willem van Schaik wrote an intermediate level program that had +all the most important features of \fBpnmtopng\fP, plus the alpha channel +handling of \fBpamrgbatopng\fP, with nice, simple code. That was +\fBpamtopng\fP. +.PP +Because \fBpamrgbatopng\fP had no options, \fBpamtopng\fP was backward +compatible with it without even trying. Therefore, as soon as we +added \fBpamtopng\fP to Netpbm, we removed \fBpamrgbatopng\fP and +recommended that \fBpamrgbatopng\fP be installed as an alias for +\fBpamtopng\fP. + + +.UN author +.SH AUTHOR + +Copyright (C) 1995-1997 by Alexander Lehmann and Willem van Schaik. +Copyright (C) 2015 by Willem van Schaik. +.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/pamtopng.html +.PP
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