The Independent JPEG Group's JPEG software v9b

This commit is contained in:
Guido Vollbeding
2016-01-17 00:00:00 +00:00
committed by DRC
parent fc11193e7a
commit a560e4b423
53 changed files with 7614 additions and 5008 deletions

23
djpeg.1
View File

@@ -1,4 +1,4 @@
.TH DJPEG 1 "23 November 2013"
.TH DJPEG 1 "26 July 2015"
.SH NAME
djpeg \- decompress a JPEG file to an image file
.SH SYNOPSIS
@@ -55,11 +55,16 @@ default options are chosen for highest quality output.) Currently, this is
equivalent to \fB\-dct fast \-nosmooth \-onepass \-dither ordered\fR.
.TP
.B \-grayscale
Force gray-scale output even if JPEG file is color. Useful for viewing on
monochrome displays; also,
Force grayscale output even if JPEG file is color.
Useful for viewing on monochrome displays; also,
.B djpeg
runs noticeably faster in this mode.
.TP
.B \-rgb
Force RGB output even if JPEG file is grayscale.
This is provided to support applications that don't
want to cope with grayscale as a separate case.
.TP
.BI \-scale " M/N"
Scale the output image by a factor M/N. Currently supported scale factors are
M/N with all M from 1 to 16, where N is the source DCT size, which is 8 for
@@ -76,7 +81,7 @@ emitted if
.B \-colors
or
.B \-grayscale
is specified, or if the JPEG file is gray-scale; otherwise, 24-bit full-color
is specified, or if the JPEG file is grayscale; otherwise, 24-bit full-color
format is emitted.
.TP
.B \-gif
@@ -90,12 +95,12 @@ emitted if
.B \-colors
or
.B \-grayscale
is specified, or if the JPEG file is gray-scale; otherwise, 24-bit full-color
is specified, or if the JPEG file is grayscale; otherwise, 24-bit full-color
format is emitted.
.TP
.B \-pnm
Select PBMPLUS (PPM/PGM) output format (this is the default format).
PGM is emitted if the JPEG file is gray-scale or if
PGM is emitted if the JPEG file is grayscale or if
.B \-grayscale
is specified; otherwise PPM is emitted.
.TP
@@ -103,8 +108,8 @@ is specified; otherwise PPM is emitted.
Select RLE output format. (Requires URT library.)
.TP
.B \-targa
Select Targa output format. Gray-scale format is emitted if the JPEG file is
gray-scale or if
Select Targa output format. Grayscale format is emitted if the JPEG file is
grayscale or if
.B \-grayscale
is specified; otherwise, colormapped format is emitted if
.B \-colors
@@ -162,7 +167,7 @@ faster and needs less memory, but it produces a lower-quality image.
is ignored unless you also say
.B \-colors
.IR N .
Also, the one-pass method is always used for gray-scale output (the two-pass
Also, the one-pass method is always used for grayscale output (the two-pass
method is no improvement then).
.TP
.BI \-maxmemory " N"