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diff --git a/upstream/opensuse-leap-15-6/man1/pnmtopng.1 b/upstream/opensuse-leap-15-6/man1/pnmtopng.1 new file mode 100644 index 00000000..0f0dcd15 --- /dev/null +++ b/upstream/opensuse-leap-15-6/man1/pnmtopng.1 @@ -0,0 +1,514 @@ +\ +.\" 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 "Pnmtopng User Manual" 0 "09 October 2016" "netpbm documentation" + +.SH NAME +pnmtopng - convert a PNM image to PNG + +.UN synopsis +.SH SYNOPSIS + +\fBpnmtopng\fP +[\fB-verbose\fP] +[\fB-downscale\fP] +[\fB-interlace\fP] +[\fB-alpha=\fP\fIfile\fP] +[\fB-transparent=\fP[\fB=\fP]\fIcolor\fP] +[\fB-background=\fP\fIcolor\fP] +[\fB-palette=\fP\fIpalettefile\fP] +[\fB-gamma=\fP\fIvalue\fP] +[\fB-hist\fP] +[\fB-text=\fP\fIfile\fP] +[\fB-ztxt=\fP\fIfile\fP] +[\fB-rgb='\fP\fIwx\fP \fIwy\fP + \fIrx\fP \fIry\fP \fIgx\fP \fIgy\fP \fIbx\fP \fIby\fP\fB'\fP] +[\fB-size='\fP\fIx\fP \fIy\fP \fIunit\fP\fB'\fP] +[\fB-srgbintent=\fP\fIintent\fP] +[\fB-modtime='\fP[\fIyy\fP]\fIyy\fP\fB-\fP\fImm\fP\fB-\fP\fIdd\fP + \fIhh\fP\fB:\fP\fImm\fP\fB:\fP\fIss\fP\fB'\fP] +[\fB-nofilter\fP] +[\fB-sub\fP] +[\fB-up\fP] +[\fB-avg\fP] +[\fB-paeth\fP] +[\fB-compression=\fP\fIn\fP] +[\fB-comp_mem_level=\fP\fIn\fP] +[\fB-comp_strategy=\fP{\fBhuffman_only\fP|\fBfiltered\fP}] +[\fB-comp_method=\fP\fBdeflated\fP] +[\fB-comp_window_bits=\fP\fIn\fP] +[\fB-comp_buffer_size=\fP\fIn\fP] +[\fB-force\fP] +[\fB-libversion\fP] +[\fIpnmfile\fP] + + +.SH OPTION USAGE +.PP +Obsolete options: +.PP +[\fB-filter \fP\fIn\fP] +.PP +Options available only in older versions: +.PP +[\fB-chroma\fP \fIwx wy rx ry gx gy bx by\fP] +[\fB-phys\fP \fIx\fP \fIy\fP \fIunit\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] +.PP +Minimum unique abbreviation of option is acceptable. You may use double +hyphens instead of 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 +\fBpnmtopng\fP reads a PNM image as input and produces a PNG image as +output. +.PP +Color component values in PNG files are either eight or sixteen +bits wide, so \fBpnmtopng\fP will automatically scale colors to have +a maxval of 255 or 65535. +.PP +For a grayscale image, \fBpnmtopng\fP produces a PNG bit depth 1, +2, 4, 8 or 16. When the input image has a small maxval, the output +PNG image has a correspondingly small bit depth. But in mapping the +PNM maxval to the PNG maxval (which is by definition the maximum value +that can be represented in the number of bits), a fair amount of +distortion happens with these low maxvals. For example, with a PNM +maxval of 5 and a PNG maxval of 7, the input sample 2 becomes the +output sample 3. The input brightness is 2/5 = .40, while the output +brightness is 3/7 = .43. Note that this is not a problem if you view +the maxval as a precision, because in .4 and .43 are identical within +the precision implied by maxval 5. Indeed, if you convert this PNG +back to a maxval 5 PGM, the pixel's value will again be 2, exactly as +it was originally. But if you need precisely the same colors in the +output PNG as in the input PNM, make sure your input PNM has a maxval +which is a power of two minus one. If you can't do that, then convert +it with \fBpamdepth\fP to something with a large maxval that is a +power of two minus one (255 and 65535 are good choices) to minimize +the error. + + +.UN options +.SH OPTIONS +.PP +\fBpnmtopng\fP changed in Netpbm 10.30 (October 2005) to use the +standard Netpbm command line syntax. Before that, you could not +use double hyphens to denote an option and could not use an equal +sign to separate an option name from its value. And the options had +to come before the non-option program arguments. +.PP +Furthermore, the options \fB-chroma\fP, \fB-phys\fP, and +\fB-time\fP were replaced by \fB-rgb\fP, \fB-size\fP, and +\fB-modtime\fP, respectively. The only difference, taking +\fB-phys\fP/\fB-size\fP as an example, is that \fB-phys\fP takes +multiple program arguments as the option argument, whereas \fB-size\fP +takes a single program argument which is composed of multiple words. +E.g. The old shell command + +.nf +\f(CW + pnmtopng -phys 800 800 0 input.pnm >output.png +\fP +.fi +.PP +is equivalent to the new shell command + +.nf +\f(CW + pnmtopng -size "800 800 0" input.pnm >output.png +\fP +.fi +.PP +If you're writing a program that needs to work with both new and old +\fBpnmtopng\fP, have it first try with the new syntax, and if it fails +with "unrecognized option," fall back to the old syntax. + + +.TP +\fB-verbose\fP + Display the format of the output file. +.TP +\fB-downscale\fP + Enables scaling of maxvalues of more then 65535 to 16 bit. Since + this means loss of image data, \fBpnmtopng\fP does not do it by + default..TP +\fB-interlace\fP + Creates an interlaced PNG file (Adam7). +.TP +\fB-alpha=\fP\fIfilename\fP + This specifies the transparency (alpha) channel of the image. You supply +the transparency channel as a standard PGM transparency mask (see +the +.BR "PGM" (5)\c +\& specification. \fBpnmtopng\fP does not +necessarily represents the transparency information as a transparency channel +in the PNG format. If it can represent the transparency information through a +palette, it will do so in order to make a smaller PNG file. +\fBpnmtopng\fP even sorts the palette so it can omit the opaque colors +from the transparency part of the palette and save space for the palette. + +.TP +\fB-transparent=\fP\fIcolor\fP +\fBpnmtopng\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. If the color you specify is not present in the +image, \fBpnmtopng\fP selects instead the color in the image that is +closest to the one you specify. Closeness is measured as a Cartesian +distance between colors in RGB space. If multiple colors are +equidistant, \fBpnmtopng\fP chooses one of them arbitrarily. +.sp +However, if you prefix your color specification with +"=", e.g. + +.nf +\f(CW + -transparent =red +\fP +.fi +.sp + only the exact color you specify will be transparent. If that +color does not appear in the image, there will be no transparency. +\fBpnmtopng\fP issues an information message when this is the case. + +.TP +\fB-background=\fP\fIcolor\fP +Causes \fBpnmtopng\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-palette=\fP\fIpalettefile\fP +This option specifies a palette to use in the PNG. It forces +\fBpnmtopng\fP to create the paletted (colormapped) variety of PNG -- +if that isn't possible, \fBpnmtopng\fP fails. If the palette you +specify doesn't contain exactly the colors in the image, +\fBpnmtopng\fP fails. Since \fBpnmtopng\fP will automatically +generate a paletted PNG, with a correct palette, when appropriate, the +only reason you would specify the \fB-palette\fP option is if you care +in what order the colors appear in the palette. The PNG palette has colors +in the same order as the palette you specify. +.sp +You specify the palette by naming a PPM file that has one pixel for +each color in the palette. +.sp +Alternatively, consider the case that have a palette and you want +to make sure your PNG contains only colors from the palette, +approximating if necessary. You don't care what indexes the PNG uses +internally for the colors (i.e. the order of the PNG palette). In +this case, you don't need \fB-palette\fP. Pass the Netpbm input +image and your palette PPM through \fBpnmremap\fP. Though you might +think it would, using \fB-palette\fP in this case wouldn't even save +\fBpnmtopng\fP any work. + +.TP +\fB-gamma=\fP\fIvalue\fP +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=.52\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-hist\fP +Use this parameter to create a chunk that specifies the frequency +(or histogram) of the colors in the image. + +.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, unless the +key for the text string starts with 'A' or 'T'. This +odd exception exists for backward compatibility; we don't know why the program +was originally designed this way, except that the distinction was meant to +roughly identify the keys 'Author' and 'Title'. + + +.TP +\fB-rgb=\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. +.sp +This option was new in Netpbm 10.30 (October 2005). Before that, +the option \fB-chroma\fP does the same thing, but with slightly +different syntax. + +.TP +\fB-size="\fP\fIx\fP \fIy\fP \fIunit\fP\fB"\fP +This option determines the aspect ratio of the individual pixels +of your image as well as the physical resolution of it. +.sp +\fIunit\fP is either \fB0\fP or \fI1\fP. When it is \fI1\fP, +the option specifies the physical resolution of the image in pixels +per meter. For example, \fB-size="10000 15000 1"\fP means +that when someone displays the image, he should make it so that 10,000 +pixels horizontally occupy 1 meter and 15,000 pixels vertically occupy +one meter. And even if he doesn't take this advice on the overall +size of the displayed image, he should at least make it so that each +pixel displays as 1.5 times as high as wide. +.sp +When \fIunit\fP is \fB0\fP, that means there is no advice on +the absolute physical resolution; just on the ratio of horizontal to +vertical physical resolution. +.sp +This information goes into the PNG's pHYS chunk. +.sp +When you don't specify \fB-size\fP, \fBpnmtopng\fP creates the image +with no pHYS chunk, which means square pixels of no absolute resolution. +.sp +This option was new in Netpbm 10.30 (October 2005). Before that, +the option \fB-phys\fP does the same thing, but with slightly +different syntax. + +.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 \fBpnmtopng\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 + +.sp +This option was new in Netpbm 10.71 (June 2015). Before that, +\fBpnmtopng\fP never generates an sRGB chunk. + +.TP +\fB-modtime="\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 digit or four digit value. +.sp +This option was new in Netpbm 10.30 (October 2005). Before that, +the option \fB-time\fP does the same thing, but with slightly +different syntax. + +.TP +\fB-filter=\fP\fIn\fP +This option is obsolete. Before Netpbm 10.22 (April 2004), this was +the only way to specify a row filter. It specifies a single type of +row filter, by number, that \fBpnmtopng\fP must use on each row. +.sp +Use \fB-nofilter\fP, \fB-sub\fP, \fB-up\fP, \fB-avg\fP, and +\fB-paeth\fP in current Netpbm. + +.TP +\fB-nofilter\fP +.TP +\fB-sub\fP +.TP +\fB-up\fP +.TP +\fB-avg\fP +.TP +\fB-paeth\fP +Each of these options permits \fBpnmtopng\fP to use one type of +row filter. \fBpnmtopng\fP chooses whichever of the permitted +filters it finds to be optimal. If you specify none of these options, +it is the same as specifying all of them -- \fBpnmtopng\fP uses any +row filter type it finds optimal. +.sp +These options were new with Netpbm 10.22 (April 2004). Before that, +you could use the \fB-filter\fP option to specify one permitted row +filter type. The default, when you specify no filter options, was the +same. + +.TP +\fB-compression=\fP\fIn\fP +This option sets set the compression level of the zlib +compression. Select a level from 0 for no compression (maximum speed) +to 9 for maximum compression (minimum speed). +.sp +The default is the default of the zlib library. + +.TP +\fB-comp_mem_level=\fP\fIn\fP +This option sets the memory usage level of the zlib compression. +Select a level from 1 for minimum memory usage (and minimum speed) to +9 for maximum memory usage (and speed). +.sp +The default is the default of the zlib library. +.sp +This option was new in Netpbm 10.30 (October 2005). + +.TP +\fB-comp_strategy=\fP{\fBhuffman_only\fP|\fBfiltered\fP} +This options sets the compression strategy of the zlib compression. +See Zlib documentation for information on what these strategies are. +.sp +The default is the default of the zlib library. +.sp +This option was new in Netpbm 10.30 (October 2005). + +.TP +\fB-comp_method=\fP\fBdeflated\fP +This option does nothing. It is here for mathematical +completeness and for possible forward compatibility. It theoretically +selects the compression method of the zlib compression, but the Z +library knows only one method today, so there's nothing to choose. +.sp +The default is the default of the zlib library. +.sp +This option was new in Netpbm 10.30 (October 2005). + +.TP +\fB-comp_window_bits=\fP\fIN\fP +This option tells how big a window the zlib compression algorithm +uses. The value is the base 2 logarithm of the window size in bytes, +so 8 means 256 bytes. The value must be from 8 to 15 (i.e. 256 bytes +to 32K). +.sp +See Zlib documentation for details on what this window size is. +.sp +The default is the default of the zlib library. +.sp +This option was new in Netpbm 10.30 (October 2005). + +.TP +\fB-comp_buffer_size\fP=\fIN\fP +This option determines in what size pieces \fBpnmtopng\fP does the +zlib compression. One compressed piece goes in each IDAT chunk in the +PNG. So the bigger this value, the fewer IDAT chunks your PNG will have. +Theoretically, this makes the PNG smaller because 1) you have less +per-IDAT-chunk overhead, and 2) the compression algorithm has more data +to work with. But in reality, the difference will probably not be +noticeable above about 8K, which is the default. +.sp +The value \fIn\fP is the size of the compressed piece (i.e. the +compression buffer) in bytes. +.sp +This option was new in Netpbm 10.30 (October 2005). + + +.TP +\fB-force\fP +When you specify this, \fBpnmtopng\fP limits its optimizations. The +resulting PNG output is as similar to the Netpbm input as possible. For +example, the PNG output will not be paletted and the transparency channel will +be represented as a full transparency channel even if the information could be +represented more succinctly with a transparency chunk. + + +.TP +\fB-libversion\fP +This option causes \fBpnmtopng\fP to display version information +about itself and the libraries it uses, \fBin addition to all its +normal function\fP. Do not confuse this with the Netpbm common +option \fB-version\fP, which causes the program to display version +information about the Netpbm library and do nothing else. +.sp +You can't really use this option in a program that invokes +\fBpnmtopng\fP and needs to know which version it is. Its function +has changed too much over the history of \fBpnmtopng\fP. The option +is good only for human eyes. + + + +.UN seealso +.SH SEE ALSO +.BR "pngtopam" (1)\c +\&, +.BR "pamtopng" (1)\c +\&, +.BR "pnmremap" (1)\c +\&, +.BR "pnmgamma" (1)\c +\&, +.BR "pnm" (5)\c +\& +.PP +For information on the PNG format, see +.UR http://schaik.com/png +http://schaik.com/png +.UE +\&. + +.UN author +.SH AUTHOR + +Copyright (C) 1995-1997 by Alexander Lehmann and 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/pnmtopng.html +.PP
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