handle ushort-component pngs, throw errors on adam7 interlaced pngs for now

db4
Doug Coleman 2009-10-06 00:33:29 -05:00
parent 7c01c09f21
commit 8dff4776c6
1 changed files with 29 additions and 5 deletions

View File

@ -26,6 +26,9 @@ CONSTANT: indexed-color 3
CONSTANT: greyscale-alpha 4
CONSTANT: truecolor-alpha 6
CONSTANT: interlace-none 0
CONSTANT: interlace-adam7 1
: <loading-png> ( -- image )
loading-png new
V{ } clone >>chunks ;
@ -86,8 +89,8 @@ ERROR: unimplemented-color-type image ;
: png-bytes-per-pixel ( loading-png -- n )
dup color-type>> {
{ 2 [ scale-bit-depth 3 * ] }
{ 6 [ scale-bit-depth 4 * ] }
{ truecolor [ scale-bit-depth 3 * ] }
{ truecolor-alpha [ scale-bit-depth 4 * ] }
[ unknown-color-type ]
} case ; inline
@ -118,20 +121,41 @@ ERROR: unimplemented-color-type image ;
lines dup first length 0 <array> prefix
[ n 1 - 0 <array> prepend ] map
2 clump [
n swap first2 [ ] [ n 1 - swap nth ] [ [ 0 n 1 - ] dip set-nth ] tri
n swap first2
[ ]
[ n 1 - swap nth ]
[ [ 0 n 1 - ] dip set-nth ] tri
png-unfilter-line
] map B{ } concat-as ;
ERROR: unimplemented-interlace ;
: reverse-interlace ( byte-array loading-png -- byte-array )
{
{ interlace-none [ ] }
{ interlace-adam7 [ unimplemented-interlace ] }
[ unimplemented-interlace ]
} case ;
: png-image-bytes ( loading-png -- byte-array )
[ png-bytes-per-pixel ]
[ inflate-data ]
[ [ inflate-data ] [ interlace-method>> ] bi reverse-interlace ]
[ png-group-width ] tri group reverse-png-filter ;
ERROR: unknown-component-type n ;
: png-component ( loading-png -- obj )
bit-depth>> {
{ 8 [ ubyte-components ] }
{ 16 [ ushort-components ] }
[ unknown-component-type ]
} case ;
: loading-png>image ( loading-png -- image )
[ image new ] dip {
[ png-image-bytes >>bitmap ]
[ [ width>> ] [ height>> ] bi 2array >>dim ]
[ drop ubyte-components >>component-type ]
[ png-component >>component-type ]
} cleave ;
: decode-greyscale ( loading-png -- image )