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move the png filtering code to images.png

db4
Doug Coleman 2009-09-26 20:09:16 -05:00
parent 16cf080393
commit 030351ef87
2 changed files with 35 additions and 42 deletions
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42
basis/compression/inflate/inflate.factor
View File

@ -1,10 +1,9 @@
! Copyright (C) 2009 Marc Fauconneau.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors arrays assocs byte-arrays
byte-vectors combinators fry grouping hashtables
compression.huffman images io.binary kernel locals
math math.bitwise math.order math.ranges multiline sequences
sorting ;
USING: accessors arrays assocs byte-vectors combinators
compression.huffman fry hashtables io.binary kernel locals math
math.bitwise math.order math.ranges sequences sorting ;
QUALIFIED-WITH: bitstreams bs
IN: compression.inflate
QUALIFIED-WITH: bitstreams bs
@ -177,42 +176,9 @@ CONSTANT: dist-table
case
]
[ produce ] keep call suffix concat ;
! [ produce ] keep dip swap suffix
:: paeth ( a b c -- p )
a b + c - { a b c } [ [ - abs ] keep 2array ] with map
sort-keys first second ;
:: png-unfilter-line ( prev curr filter -- curr' )
prev :> c
prev 3 tail-slice :> b
curr :> a
curr 3 tail-slice :> x
x length [0,b)
filter {
{ 0 [ drop ] }
{ 1 [ [| n | n x nth n a nth + 256 wrap n x set-nth ] each ] }
{ 2 [ [| n | n x nth n b nth + 256 wrap n x set-nth ] each ] }
{ 3 [ [| n | n x nth n a nth n b nth + 2/ + 256 wrap n x set-nth ] each ] }
{ 4 [ [| n | n x nth n a nth n b nth n c nth paeth + 256 wrap n x set-nth ] each ] }
} case
curr 3 tail ;
PRIVATE>
: reverse-png-filter' ( lines -- byte-array )
[ first ] [ 1 tail ] [ map ] bi-curry@ bi nip
concat [ 128 + ] B{ } map-as ;
: reverse-png-filter ( lines -- byte-array )
dup first length 0 <array> prefix
[ { 0 0 } prepend ] map
2 clump [
first2 dup [ third ] [ [ 0 2 ] dip set-nth ] bi
png-unfilter-line
] map B{ } concat-as ;
: zlib-inflate ( bytes -- bytes )
bs:<lsb0-bit-reader>
[ check-zlib-header ] [ inflate-loop ] bi

35
basis/images/png/png.factor
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@ -1,9 +1,9 @@
! Copyright (C) 2009 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors images io io.binary io.encodings.ascii
io.encodings.binary io.encodings.string io.files io.files.info kernel
sequences io.streams.limited fry combinators arrays math checksums
checksums.crc32 compression.inflate grouping byte-arrays images.loader ;
USING: accessors arrays checksums checksums.crc32 combinators
compression.inflate fry grouping images images.loader io
io.binary io.encodings.ascii io.encodings.string kernel locals
math math.bitwise math.ranges sequences sorting ;
IN: images.png
SINGLETON: png-image
@ -90,6 +90,33 @@ ERROR: unknown-filter-method image ;
[ unknown-color-type ]
} case ;
:: paeth ( a b c -- p )
a b + c - { a b c } [ [ - abs ] keep 2array ] with map
sort-keys first second ;
:: png-unfilter-line ( prev curr filter -- curr' )
prev :> c
prev 3 tail-slice :> b
curr :> a
curr 3 tail-slice :> x
x length [0,b)
filter {
{ filter-none [ drop ] }
{ filter-sub [ [| n | n x nth n a nth + 256 wrap n x set-nth ] each ] }
{ filter-up [ [| n | n x nth n b nth + 256 wrap n x set-nth ] each ] }
{ filter-average [ [| n | n x nth n a nth n b nth + 2/ + 256 wrap n x set-nth ] each ] }
{ filter-paeth [ [| n | n x nth n a nth n b nth n c nth paeth + 256 wrap n x set-nth ] each ] }
} case
curr 3 tail ;
: reverse-png-filter ( lines -- byte-array )
dup first length 0 <array> prefix
[ { 0 0 } prepend ] map
2 clump [
first2 dup [ third ] [ [ 0 2 ] dip set-nth ] bi
png-unfilter-line
] map B{ } concat-as ;
: filter-png ( groups loading-png -- byte-array )
filter-method>> {
{ filter-none [ reverse-png-filter ] }