IMG2SIXEL(1)IMG2SIXEL(1)NAMEimg2sixel - image converter to DEC SIXEL graphics
SYNOPSISimg2sixel [ -options ] imagefiles
img2sixel [ -options ] < imagefiles
DESCRIPTIONimg2sixel convert JPEG/PNG images into DEC SIXEL image format.
COMMAND-LINE OPTIONS
img2sixel has the following command-line options:
-7, --7bit-mode
generate a sixel image for 7bit terminals or printers (default).
-8, --8bit-mode
generate a sixel image for 8bit terminals or printers.
-p COLORS, --colors=COLORS
specify number of colors to reduce the image to (default=256).
-m FILE, --mapfile=FILE
transform image colors to match this set of colorsspecify map.
-e, --monochrome
output monochrome sixel image. this option assumes the terminal
background color is black.
-i, --invert
assume the terminal background color is white. make sense only
when -e option is given.
-I, --high-color
output 15bpp sixel image
-u, --use-macro
use DECDMAC and DEVINVM sequences to optimize GIF animation ren‐
dering.
-n MACRONO, --macro-number=MACRONO
specify an number argument for DECDMAC and make terminal memorize
SIXEL image. No image is shown if this option is specified
-C COMPLEXIONSCORE, --complexion-score=COMPLEXIONSCORE
specify an number argument for the score of complexion correction.
COMPLEXIONSCORE must be 1 or more.
-g, --ignore-delay
render GIF animation without delay.
-S, --static
render animated GIF as a static image.
-d DIFFUSIONTYPE, --diffusion=DIFFUSIONTYPE
choose diffusion method which used with color reduction.
DIFFUSIONTYPE is one of them:
auto -> choose diffusion type automatically (default)
none -> do not diffusion
fs -> Bill Atkinson's method
atkinson -> Floyd-Steinberg method
jajuni -> Jarvis, Judice & Ninke
stucki -> Stucki's method
burkes -> Burkes' method
-f FINDTYPE, --find-largest=FINDTYPE
choose method for finding the largest dimension of median cut
boxes for splitting, make sense only when -p option (color reduc‐
tion) is specified.
FINDTYPE is one of them:
auto -> choose finding method automatically (default)
norm -> simply comparing the range in RGB space
lum -> transforming into luminosities before the comparison
-s SELECTTYPE, --select-color=SELECTTYPE
choose the method for selecting representative color from each
median-cut box, make sense only when -p option (color reduction)
is specified.
SELECTTYPE is one of them:
auto -> choose selecting method automatically (default)
center -> choose the center of the box
average -> calculate the color average into the box
histogram -> similar with average but considers color histogram
-c REGION, --crop=REGION
crop source image to fit the specified geometry.
REGION should be formatted as '%dx%d+%d+%d'.
-w WIDTH, --width=WIDTH
resize image to specified width.
WIDTH is represented by the following syntax:
auto -> preserving aspect ratio (default)
<number>% -> scale width with given percentage
<number> -> scale width with pixel counts
<number>px -> scale width with pixel counts
-h HEIGHT, --height=HEIGHT
resize image to specified height.
HEIGHT is represented by the following syntax
auto -> preserving aspect ratio (default)
<number>% -> scale height with given percentage
<number> -> scale height with pixel counts
<number>px -> scale height with pixel counts
-r RESAMPLINGTYPE, --resampling=RESAMPLINGTYPE
choose resampling method used with -w or -h option (scaling).
RESAMPLINGTYPE is one of them:
nearest -> Nearest-Neighbor method
gaussian -> Gaussian filter
hanning -> Hanning filter
hamming -> Hamming filter
bilinear -> Bilinear filter (default)
welsh -> Welsh filter
bicubic -> Bicubic filter
lanczos2 -> Lanczos-2 filter
lanczos3 -> Lanczos-3 filter
lanczos4 -> Lanczos-4 filter
-q QUALITYMODE, --quality=QUALITYMODE
select quality of color quanlization.
QUALITYMODE is one of them:
auto -> decide quality mode automatically (default)
high -> high quality and low speed mode
low -> low quality and high speed mode
full -> quality and careful speed mode
-l LOOPMODE, --loop-control=LOOPMODE
select loop control mode for GIF animation.
auto -> honer the setting of GIF header (default)
force -> always enable loop
disable -> always disable loop
-t PALETTETYPE, --palette-type=PALETTETYPE
select palette color space type.
auto -> choose palette type automatically (default)
hls -> use HLS color space
rgb -> use RGB color space
-b BUILTINPALETTE, --builtin-palette=BUILTINPALETTE
select built-in palette type
xterm16 -> X default 16 color map
xterm256 -> X default 256 color map
vt340mono -> VT340 monochrome map
vt340color -> VT340 color map
-E ENCODEPOLICY, --encode-policy=ENCODEPOLICY
select encoding policy
auto -> choose encoding policy automatically (default)
fast -> encode as fast as possible
size -> encode to as small sixel sequence as possible
-P, --penetrate
penetrate GNU Screen using DCS pass-through sequence.
-D, --pipe-mode
read source images from stdin continuously.
-v, --verbose
show debugging info.
-V, --version
show version and license info.
-H, --help
print help.
SEE ALSOsixel(5)sixel2png(1)AUTHORSimg2sixel is maintained by Hayaki Saito. We imported whole code of
stbi-1.41, written by Sean Barrett and its contributers, for loading
PNG/JPEG images, and imported some code from pnmquant.c (netpbm
library) for image quantization.
COPYRIGHT
Copyright (c) 2014 Hayaki Saito
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Soft‐
ware"), to deal in the Software without restriction, including without
limitation the rights to use, copy, modify, merge, publish, distribute,
sublicense, and/or sell copies of the Software, and to permit persons
to whom the Software is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MER‐
CHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFT‐
WARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
THANKS
This software derives from the following implementations.
stbi-1.41
This software includes stbi-1.41 (stb_image.h), a public domain
JPEG/PNG reader.
https://github.com/nothings/stb
pnmquant.c (netpbm library)
The implementation of median cut algorithm for color quantization
in quant.c is imported from pnmcolormap included in netpbm
library.
http://netpbm.sourceforge.net/
pnmcolormap was derived from ppmquant, originally by Jef
Poskanzer.
Copyright (C) 1989, 1991 by Jef Poskanzer.
Copyright (C) 2001 by Bryan Henderson.
Permission to use, copy, modify, and distribute this software and
its documentation for any purpose and without fee is hereby
granted, provided that the above copyright notice appear in all
copies and that both that copyright notice and this permission
notice appear in supporting documentation. This software is pro‐
vided "as is" without express or implied warranty.
monosixel (arakiken's tw)
The pattern dither algorithm implemented in quant.c is imported
from monosixel/main.c in arakiken's tw "sixel" branch.
https://bitbucket.org/arakiken/tw/branch/sixel
This tool is written by Araki Ken, and we regard it as a deriva‐
tive of. original tw, created by Sho Hashimoto.
Copyright (c) 2012 Sho Hashimoto
Copyright (c) 2014 Araki Ken
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without restric‐
tion, including without limitation the rights to use, copy, mod‐
ify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is fur‐
nished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGE‐
MENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
sixel 2014-3-2
some part of converters/loader.c are derived from kmiya's "sixel"
original version (2014-3-2).
http://nanno.dip.jp/softlib/man/rlogin/sixel.tar.gz
It is written by kmiya@culti.
He distributes it under very permissive license which permits use‐
ing, copying, modification, redistribution, and all other public
activities without any restrictions.
He declares this is compatible with MIT/BSD/GPL.
REFERENCES
resize.c (ImageMagick)
We added some resampling filters in reference to the line-up of
filters of MagickCore's resize.c.
http://www.imagemagick.org/api/MagickCore/resize_8c_source.html
CONTRIBUTORS
Araki Ken (@arakiken),
Iwamoto Kouichi (@ttdoda)
Kazuhiro YOSHIKAWA (@yoshikaw)
BUGS
· Send bug-reports, fixes, enhancements to user@zuse.jp.
4th Berkeley Distribution May 2014 IMG2SIXEL(1)
