--- /dev/null
+! Copyright (C) 2009 Doug Coleman, Keith Lazuka
+! See http://factorcode.org/license.txt for BSD license.
+USING: accessors combinators io kernel math namespaces
+prettyprint sequences vectors ;
+QUALIFIED-WITH: bitstreams bs
+IN: compression.lzw-gif
+
+SYMBOL: clear-code
+4 clear-code set-global
+
+SYMBOL: end-of-information
+5 end-of-information set-global
+
+TUPLE: lzw input output table code old-code initial-code-size code-size ;
+
+SYMBOL: table-full
+
+: initial-uncompress-table ( -- seq )
+ end-of-information get 1 + iota [ 1vector ] V{ } map-as ;
+
+: reset-lzw-uncompress ( lzw -- lzw )
+ initial-uncompress-table >>table
+ dup initial-code-size>> >>code-size ;
+
+: <lzw-uncompress> ( code-size input -- obj )
+ lzw new
+ swap >>input
+ swap >>initial-code-size
+ dup initial-code-size>> >>code-size
+ BV{ } clone >>output
+ reset-lzw-uncompress ;
+
+ERROR: not-in-table value ;
+
+: lookup-old-code ( lzw -- vector )
+ [ old-code>> ] [ table>> ] bi nth ;
+
+: lookup-code ( lzw -- vector )
+ [ code>> ] [ table>> ] bi nth ;
+
+: code-in-table? ( lzw -- ? )
+ [ code>> ] [ table>> length ] bi < ;
+
+: code>old-code ( lzw -- lzw )
+ dup code>> >>old-code ;
+
+: write-code ( lzw -- )
+ [ lookup-code ] [ output>> ] bi push-all ;
+
+: maybe-increment-code-size ( lzw -- lzw )
+ dup [ table>> length ] [ code-size>> 2^ ] bi =
+ [ [ 1 + ] change-code-size ] when ;
+
+: add-to-table ( seq lzw -- )
+ [ table>> push ]
+ [ maybe-increment-code-size 2drop ] 2bi ;
+
+: lzw-read ( lzw -- lzw n )
+ [ ] [ code-size>> ] [ input>> ] tri bs:read ;
+
+DEFER: lzw-uncompress-char
+: handle-clear-code ( lzw -- )
+ reset-lzw-uncompress
+ lzw-read dup end-of-information get = [
+ 2drop
+ ] [
+ >>code
+ [ write-code ]
+ [ code>old-code ] bi
+ lzw-uncompress-char
+ ] if ;
+
+: handle-uncompress-code ( lzw -- lzw )
+ dup code-in-table? [
+ [ write-code ]
+ [
+ [
+ [ lookup-old-code ]
+ [ lookup-code first ] bi suffix
+ ] [ add-to-table ] bi
+ ] [ code>old-code ] tri
+ ] [
+ [
+ [ lookup-old-code dup first suffix ] keep
+ [ output>> push-all ] [ add-to-table ] 2bi
+ ] [ code>old-code ] bi
+ ] if ;
+
+: lzw-uncompress-char ( lzw -- )
+ lzw-read [
+ >>code
+ dup code>> end-of-information get = [
+ drop
+ ] [
+ dup code>> clear-code get = [
+ handle-clear-code
+ ] [
+ handle-uncompress-code
+ lzw-uncompress-char
+ ] if
+ ] if
+ ] [
+ drop
+ ] if* ;
+
+: register-special-codes ( first-code-size -- )
+ [
+ 1 - 2^ dup clear-code set
+ 1 + end-of-information set
+ ] keep ;
+
+: lzw-uncompress ( code-size seq -- byte-array )
+ [ register-special-codes ] dip
+ bs:<lsb0-bit-reader>
+ <lzw-uncompress>
+ [ lzw-uncompress-char ] [ output>> ] bi ;
! Copyright (C) 2009 Keith Lazuka.
! See http://factorcode.org/license.txt for BSD license.
-USING: accessors images.gif io io.encodings.binary io.files
-math namespaces sequences tools.test math.bitwise ;
+USING: accessors bitstreams compression.lzw-gif images.gif io
+io.encodings.binary io.files kernel math math.bitwise
+math.parser namespaces prettyprint sequences tools.test ;
+QUALIFIED-WITH: bitstreams bs
IN: images.gif.tests
: path>gif ( path -- loading-gif )
binary [ input-stream get load-gif ] with-file-reader ;
: gif-example1 ( -- loading-gif )
- "resource:extra/images/testing/symbol-word-16-colors.gif" path>gif ;
+ "resource:extra/images/testing/symbol-word.gif" path>gif ;
: gif-example2 ( -- loading-gif )
"resource:extra/images/testing/check-256-colors.gif" path>gif ;
: gif-example3 ( -- loading-gif )
"resource:extra/images/testing/monochrome.gif" path>gif ;
+: gif-example4 ( -- loading-gif )
+ "resource:extra/images/testing/noise.gif" path>gif ;
+
: declared-num-colors ( gif -- n ) flags>> 3 bits 1 + 2^ ;
: actual-num-colors ( gif -- n ) global-color-table>> length 3 /i ;
[ 2 ] [ gif-example3 actual-num-colors ] unit-test
[ 2 ] [ gif-example3 declared-num-colors ] unit-test
+
+: >index-stream ( gif -- seq )
+ [ image-descriptor>> first-code-size>> ]
+ [ compressed-bytes>> ] bi
+ lzw-uncompress ;
+
+[
+ BV{
+ 0 0 0 0 0 0
+ 1 0 0 0 0 1
+ 1 1 0 0 1 1
+ 1 1 1 1 1 1
+ 1 0 1 1 0 1
+ 1 0 0 0 0 1
+ }
+] [ gif-example3 >index-stream ] unit-test
+
+
! Copyrigt (C) 2009 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
-USING: accessors arrays combinators constructors destructors
-images images.loader io io.binary io.buffers
-io.encodings.binary io.encodings.string io.encodings.utf8
-io.files io.files.info io.ports io.streams.limited kernel make
-math math.bitwise math.functions multiline namespaces
-prettyprint sequences ;
+USING: accessors arrays assocs combinators compression.lzw-gif
+constructors destructors grouping images images.loader io
+io.binary io.buffers io.encodings.binary io.encodings.string
+io.encodings.utf8 io.files io.files.info io.ports
+io.streams.limited kernel make math math.bitwise math.functions
+multiline namespaces prettyprint sequences ;
IN: images.gif
SINGLETON: gif-image
block-terminator ;
TUPLE: image-descriptor
-left top width height flags lzw-min-code-size ;
+left top width height flags first-code-size ;
TUPLE: plain-text-extension
introducer label block-size text-grid-left text-grid-top text-grid-width
2 read le> >>width
2 read le> >>height
1 read le> >>flags
- 1 read le> >>lzw-min-code-size ;
+ 1 read le> 1 + >>first-code-size ;
: read-graphic-control-extension ( -- graphic-control-extension )
\ graphics-control-extension new
: read-global-color-table ( loading-gif -- loading-gif )
dup color-table? [
- dup color-table-size read >>global-color-table
+ dup color-table-size read 3 group >>global-color-table
] when ;
: maybe-read-local-color-table ( loading-gif -- loading-gif )
} case
] with-input-stream ;
+: decompress ( loading-gif -- indexes )
+ [ image-descriptor>> first-code-size>> ]
+ [ compressed-bytes>> ] bi
+ lzw-uncompress ;
+
+: apply-palette ( indexes palette -- bitmap )
+ [ nth 255 suffix ] curry V{ } map-as concat ;
+
+: dimensions ( loading-gif -- dim )
+ [ image-descriptor>> width>> ] [ image-descriptor>> height>> ] bi 2array ;
+
: loading-gif>image ( loading-gif -- image )
- ;
+ [ <image> ] dip
+ [ dimensions >>dim ]
+ [ drop RGBA >>component-order ubyte-components >>component-type ]
+ [
+ [ decompress ] [ global-color-table>> ] bi
+ apply-palette >>bitmap
+ ] tri ;
ERROR: loading-gif-error gif-image ;
projects / factor.git / commitdiff
