| 1 | .\" $Header: /cvs/maptools/cvsroot/libtiff/man/rgb2ycbcr.1,v 1.3 2005/11/02 11:07:19 dron Exp $ |
| 2 | .\" |
| 3 | .\" Copyright (c) 1991-1997 Sam Leffler |
| 4 | .\" Copyright (c) 1991-1997 Silicon Graphics, Inc. |
| 5 | .\" |
| 6 | .\" Permission to use, copy, modify, distribute, and sell this software and |
| 7 | .\" its documentation for any purpose is hereby granted without fee, provided |
| 8 | .\" that (i) the above copyright notices and this permission notice appear in |
| 9 | .\" all copies of the software and related documentation, and (ii) the names of |
| 10 | .\" Sam Leffler and Silicon Graphics may not be used in any advertising or |
| 11 | .\" publicity relating to the software without the specific, prior written |
| 12 | .\" permission of Sam Leffler and Silicon Graphics. |
| 13 | .\" |
| 14 | .\" THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, |
| 15 | .\" EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY |
| 16 | .\" WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. |
| 17 | .\" |
| 18 | .\" IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR |
| 19 | .\" ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, |
| 20 | .\" OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, |
| 21 | .\" WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF |
| 22 | .\" LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE |
| 23 | .\" OF THIS SOFTWARE. |
| 24 | .\" |
| 25 | .if n .po 0 |
| 26 | .TH RGB2YCBCR 1 "November 2, 2005" "libtiff" |
| 27 | .SH NAME |
| 28 | rgb2ycbcr \- convert non-YCbCr |
| 29 | .SM TIFF |
| 30 | images to a YCbCr |
| 31 | .SM TIFF |
| 32 | image |
| 33 | .SH SYNOPSIS |
| 34 | .B rgb2ycbcr |
| 35 | [ |
| 36 | .I options |
| 37 | ] |
| 38 | .I "src1.tif src2.tif ... dst.tif" |
| 39 | .SH DESCRIPTION |
| 40 | .I rgb2ycbcr |
| 41 | converts |
| 42 | .SM RGB |
| 43 | color, greyscale, or bi-level |
| 44 | .SM TIFF |
| 45 | images to YCbCr images by transforming and sampling pixel data. If multiple |
| 46 | files are specified on the command line each source file is converted to a |
| 47 | separate directory in the destination file. |
| 48 | .PP |
| 49 | By default, chrominance samples are created by sampling |
| 50 | 2 by 2 blocks of luminance values; this can be changed with the |
| 51 | .B \-h |
| 52 | and |
| 53 | .B \-v |
| 54 | options. |
| 55 | Output data are compressed with the |
| 56 | .SM PackBits |
| 57 | compression scheme, by default; an alternate scheme can be selected with the |
| 58 | .B \-c |
| 59 | option. |
| 60 | By default, output data are compressed in strips with |
| 61 | the number of rows in each strip selected so that the |
| 62 | size of a strip is never more than 8 kilobytes; |
| 63 | the |
| 64 | .B \-r |
| 65 | option can be used to explicitly set the number of |
| 66 | rows per strip. |
| 67 | .SH OPTIONS |
| 68 | .TP |
| 69 | .B \-c |
| 70 | Specify a compression scheme to use when writing image data: |
| 71 | .B "\-c none" |
| 72 | for no compression, |
| 73 | .B "-c packbits" |
| 74 | for the PackBits compression algorithm (the default), |
| 75 | .B "-c jpeg" |
| 76 | for the JPEG compression algorithm, |
| 77 | .B "-c zip" |
| 78 | for the deflate compression algorithm, |
| 79 | and |
| 80 | .B "\-c lzw" |
| 81 | for Lempel-Ziv & Welch. |
| 82 | .TP |
| 83 | .B \-h |
| 84 | Set the horizontal sampling dimension to one of: 1, 2 (default), or 4. |
| 85 | .TP |
| 86 | .B \-r |
| 87 | Write data with a specified number of rows per strip; |
| 88 | by default the number of rows/strip is selected so that each strip |
| 89 | is approximately 8 kilobytes. |
| 90 | .TP |
| 91 | .B \-v |
| 92 | Set the vertical sampling dimension to one of: 1, 2 (default), or 4. |
| 93 | .SH "SEE ALSO" |
| 94 | .BR tiffinfo (1), |
| 95 | .BR tiffcp (1), |
| 96 | .BR libtiff (3) |
| 97 | .PP |
| 98 | Libtiff library home page: |
| 99 | .BR http://www.remotesensing.org/libtiff |