From 5aace0df055cf5e6f0b655fb6475d060971c4cf4 Mon Sep 17 00:00:00 2001 From: giraffedata Date: Sat, 15 Nov 2014 03:42:53 +0000 Subject: miscellaneous update git-svn-id: http://svn.code.sf.net/p/netpbm/code/userguide@2313 9d0c8265-081b-0410-96cb-a4ca84ce46f8 --- giftopnm.html | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) (limited to 'giftopnm.html') diff --git a/giftopnm.html b/giftopnm.html index 4e41f607..01f18e3a 100644 --- a/giftopnm.html +++ b/giftopnm.html @@ -53,18 +53,19 @@ Netpbm output image has the wrong aspect ratio. In this case,
--alphaout=alpha-filename
giftopnm creates a PBM file containing the transparency -information from the input image. This "alpha image" is the same -dimensions as the input image, and each pixel of the alpha image tells whether -the corresponding pixel of the input image is transparent. Black means -transparent; white means opaque. If you don't specify --alphaout, -giftopnm does not generate an alpha file, and if the input image has an -alpha channel, giftopnm simply discards it. +information from the input image. This transparency image is the same +dimensions as the input image, and each pixel of the transparency image tells +whether the corresponding pixel of the input image is transparent. Black +means transparent; white means opaque. If you don't +specify --alphaout, giftopnm does not generate a transparency +file, and if the input image has a transparency channel, giftopnm simply +discards it.

If you specify - as the filename, giftopnm writes the -alpha output to Standard Output and discards the image. +transparency output to Standard Output and discards the image.

See pamcomp for one way to use -the alpha output file. +the transparency output file.

-verbose -- cgit 1.4.1