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Better error images for non-baseline JPEGs. 

bugfix: Handles more than one table per DHT chunk.
db4
Marc Fauconneau 2009-08-30 17:29:40 +09:00
parent bf15648b4d
commit 5a20dee2aa
1 changed files with 11 additions and 8 deletions
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17
basis/images/jpeg/jpeg.factor
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@ -6,7 +6,7 @@ images.processing io io.binary io.encodings.binary io.files
io.streams.byte-array kernel locals math math.bitwise
math.constants math.functions math.matrices math.order
math.ranges math.vectors memoize multiline namespaces
sequences sequences.deep images.loader ;
sequences sequences.deep images.loader io.streams.limited ;
IN: images.jpeg
QUALIFIED-WITH: bitstreams bs
@ -118,18 +118,18 @@ TUPLE: jpeg-color-info
] with-byte-reader ;
: decode-huff-table ( chunk -- )
data>>
binary
data>> [ binary <byte-reader> ] [ length ] bi
stream-throws limit
[
1 ! %fixme: Should handle multiple tables at once
[ input-stream get [ count>> ] [ limit>> ] bi < ]
[
read4/4 swap 2 * +
16 read
dup [ ] [ + ] map-reduce read
binary [ [ read [ B{ } ] unless* ] { } map-as ] with-byte-reader
swap jpeg> huff-tables>> set-nth
] times
] with-byte-reader ;
] while
] with-input-stream* ;
: decode-scan ( chunk -- )
data>>
@ -148,7 +148,10 @@ TUPLE: jpeg-color-info
: singleton-first ( seq -- elt )
[ length 1 assert= ] [ first ] bi ;
ERROR: not-a-baseline-jpeg-image ;
: baseline-parse ( -- )
jpeg> headers>> [ type>> { SOF 0 } = ] any? [ not-a-baseline-jpeg-image ] unless
jpeg> headers>>
{
[ [ type>> { SOF 0 } = ] filter singleton-first decode-frame ]
@ -221,7 +224,7 @@ MEMO: dct-matrix-blas ( -- m ) dct-matrix >float-blas-matrix ;
: V.M ( x A -- x.A ) Mtranspose swap M.V ;
: idct-blas ( b -- b' ) >float-blas-vector dct-matrix-blas V.M ;
: idct ( b -- b' ) idct-blas ;
: idct ( b -- b' ) idct-factor ;
:: draw-block ( block x,y color-id jpeg-image -- )
block dup length>> sqrt >fixnum group flip