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diff --git a/upstream/opensuse-leap-15-6/man1/pamtojpeg2k.1 b/upstream/opensuse-leap-15-6/man1/pamtojpeg2k.1 new file mode 100644 index 00000000..e5135d46 --- /dev/null +++ b/upstream/opensuse-leap-15-6/man1/pamtojpeg2k.1 @@ -0,0 +1,254 @@ +\ +.\" 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 "Pamtojpeg2k User Manual" 0 "31 January 2014" "netpbm documentation" + +.SH NAME +pamtojpeg2k - convert PAM/PNM image to a JPEG-2000 code stream + +.UN synopsis +.SH SYNOPSIS + +\fBpamtojpeg2k\fP +[\fB-imgareatlx=\fP\fIcolumn\fP] +[\fB-imgareatly=\fP\fIrow\fP] +[\fB-tilegrdtlx=\fP\fIcolumn\fP] +[\fB-tilegrdtly=\fP\fIrow\fP] +[\fB-tilewidth=\fP\fIcolumns\fP] +[\fB-tileheight=\fP\fIrows\fP] +[\fB-prcwidth=\fP\fIcolumns\fP] +[\fB-prcheight=\fP\fIrows\fP] +[\fB-cblkwidth=\fP\fIcolumns\fP] +[\fB-cblkheight=\fP\fIrows\fP] +[\fB-mode=\fP{\fBinteger\fP|\fBint\fP|\fBreal\fP}] +[\fB-compression=\fP\fIratio\fP] +[\fB-ilyrrates=\fP\fIratestring\fP] +[\fB-numrlvls=\fP\fInumber\fP] +[\fB-progression=\fP{\fBlrcp\fP|\fBrlcp\fP|\fBrpcl\fP|\fBpcrl\fP|\fBcprl\fP}] +[\fB-numgbits=\fP\fInumber\fP] +[\fB-nomct\fP] +[\fB-sop\fP] +[\fB-eph\fP] +[\fB-lazy\fP] +[\fB-termall\fP] +[\fB-segsym\fP] +[\fB-vcausal\fP] +[\fB-pterm\fP] +[\fB-resetprob\fP] +[\fB-verbose\fP] +[\fB-debuglevel=\fP\fInumber\fP] +\fIfilename\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 +\fBpamtojpeg2k\fP converts the named PBM, PGM, PPM, or PAM file, +or Standard Input if no file is named, to a JPEG-2000 code stream +(JPC) file on Standard Output. +.PP +The JPEG-2000 specification specifies two separate formats: JP2 +and JPEG-2000 code stream (JPC). JP2 represents a visual image quite +specifically, whereas JPC is a more or less arbitrary array of codes. +\fBpamtojpeg2k\fP can't produce a JP2, but the JPC image that +\fBpamtojpeg2k\fP produces is very similar to a JP2 if the input is a +PBM, PGM, or PPM image or equivalent PAM image. One difference is +that the RGB intensity values in a JP2 are SRGB values, while +\fBpamtojpeg2k\fP produces ITU-R Recommendation BT.709 values. Those +are very similar, but not identical. Another difference is that a JP2 +can contain extra information about an image that JPC cannot. +.PP +When the input is a PAM image other than a PBM, PGM, or PPM equivalent, +the JPC raster produced contains whatever the PAM raster does. It can have +any number of planes with any meanings; the planes are in the same order in +the JPC output as in the PAM input. +.PP +A JPC image has a "precision," which is the number of bits used for +each code (in Netpbm lingo, "sample"). Actually, it has a separate +precision for each component. \fBpamtojpeg2k\fP uses for the +precision of every component the least number of bits that can +represent the maxval of the input image. A JPC image does not have an +independent concept of maxval; the maxval of a JPC sample is the +maximum value that the number of bits specified by the precision can +represent in pure binary code. E.g. if the precision is 4, the maxval +is 15. \fBpamtojpeg2k\fP does of course scale the sample values from +the input maxval to the output maxval. Example: The input maxval is +99. This means JPC precision is 7 bits and the JPC maxval is 127. A +sample value of 33 in the input becomes a sample value of 43 in the +output. +.PP +\fBpamtojpeg2k\fP generates the JPC output with the +.UR http://www.ece.uvic.ca/~mdadams/jasper/ +Jasper JPEG-2000 library +.UE +\&. See documentation of the library for details on what +\fBpamtojpeg2k\fP produces. Note that the Jasper library contains +facilities for reading PNM images, but \fBpamtojpeg2k\fP does not use +those. It uses the Netpbm library instead. Note that the makers of +the Jasper library write it "JasPer," but Netpbm documentation follows +standard American English typography rules, which don't allow that +kind of capitalization. +.PP +Use \fBjpeg2ktopam\fP to convert in the other direction. +.PP +The program \fBjasper\fP, which is packaged with the Jasper +JPEG-2000 library, also converts between JPEG-2000 and PNM formats. +Because it's packaged with the library, it may exploit it better, +especially recently added features. However, since it does not use the +Netpbm library to read and write the Netpbm formats, it doesn't do as +good a job on that side. +.PP +Another format with goals similar to those of JPEG-2000 but that allows for +faster encoding and decoding, is +JPEG-LS. +.UR http://charls.codeplex.com +CharLS +.UE +\& is a package of +software for using JPEG-LS. + + +.UN options +.SH OPTIONS + +Most of the options are identical in name and function to options that the +Jasper library JPC encoder subroutine takes. See +.UR http://www.ece.uvic.ca/~mdadams/jasper/ +Jasper documentation +.UE +\& +for details. Here, we document only options that are not direct analogs +of Jasper options. + + + +.TP +\fB-compression=\fP\fIratio\fP +\fIratio\fP is a floating point number that specifies the compression +ratio. \fBpamtojpeg2k\fP will adjust quality as necessary to ensure that +you get this compression ratio. E.g. 4 means the output will be about +one fourth the size in bytes of the input file. +.sp +The ratio concerns just the raster part of the image, with the denominator +being what the raster would take if it were encoded the most naive way +possible (e.g. 3 bytes per pixel in 8-bit-per-sample RGB). It does, +however, include metadata that is part of the compressed raster. Because +of that, it may not be possible to give you your requested compression ratio +at any quality. If it isn't, \fBpamtojpeg2k\fP fails with a message +saying so. +.sp +If you don't specify this option, \fBpamtojpeg2k\fP gives you the best +compression it can without losing any quality. Because of the metadata issue +described above, this may mean, for a small image, the image actually expands. +.sp +Note that though the Jasper library takes a compression factor, this +option specifies a compression ratio. The compression factor is the +multiplicative inverse of (1 divided by) the compression ratio. +.sp +Before Netpbm 10.61 (December 2012), the default was a compression ratio +of 1, and if \fBpamtojpeg2k\fP could not make the output that small, it just +made it as small as it could, with zero quality. You know this is happening +when you see the warning message, "empty layer generated." + +.TP +\fB-verbose\fP +This option causes \fBpamtojpeg2k\fP to issue informational messages about +the conversion process. + +.TP +\fB-debuglevel\fP=\fInumber\fP +This option controls debug messages from the Jasper library. +\fBpamtojpeg2k\fP passes \fInumber\fP as the debug level to the Jasper +JPC encoder. + + + +.UN examples +.SH EXAMPLES +.PP +This example compresses losslessly. + +.nf + pamtojpeg2k myimg.ppm >myimg.jpc +.fi + +\fBjpeg2ktopam\fP will recreate myimg.ppm exactly. +.PP +This example compresses the file to one tenth its original size, throwing +away information as necessary. + +.nf + pamtojpeg2k -compression=10 myimg.pgm >myimg.jpc +.fi + + +.UN jpeg2000 +.SH ABOUT JPEG-2000 +.PP +JPEG-2000 is a format that compresses a visual image (or a similar set of +data) into a minimal number of bytes for storage or transmission. In that, +its goal is similar to JPEG. It has two main differences from JPEG. +.PP +One difference is that it does a much better job on most images of +throwing out information in order to achieve a smaller output. That +means when you reconstruct the image from the resulting compressed +file, it looks a lot closer to the image you started with +JPEG-2000 than with JPEG, for the same compressed file size. Or, looked +at another way, with JPEG-2000 you get a much smaller file than with +JPEG for the same image quality. +.PP +The second difference is that with JPEG-2000, you decide how much +compression you want and the compressor adjusts the quality to meet your +requirement, whereas with JPEG, you decide how much quality you want +and the compressor adjusts the size of the output to meet your requirement. +I.e. with JPEG-2000, the quality of the result depends on the compressibility +of the input, but with JPEG, the \fIsize\fP of the result depends on +the compressibility of the input. +.PP +With JPEG-2000, you can specify lossless compression, thus making it +compete with GIF and PNG. With standard JPEG, you always lose something. +(There are rumored to be variations of JPEG around that are lossless, +though). +.PP +JPEG is much older than JPEG-2000 and far more popular. JPEG is one of +the half dozen most popular graphics formats and virtually all graphics +facilities understand it. JPEG-2000 is virtually unknown. +.PP +There is no compatibility between JPEG and JPEG-2000. Programs that +read JPEG do not automatically read JPEG-2000 and vice versa. + + +.UN seealso +.SH SEE ALSO +.BR "jpeg2ktopam" (1)\c +\&, +.BR "pnmtojpeg" (1)\c +\&, +.BR "ppm" (5)\c +\&, +.BR "pgm" (5)\c +\&, +.BR "pbm" (5)\c +\&, +.BR "pam" (5)\c +\&, + +.SH History +.PP +\fBpamtojpeg2k\fP was added to Netpbm in Release 10.12 (November 2002). +.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/pamtojpeg2k.html +.PP
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