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Wed, May 8, 12:56
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R10977 RADIANCE Photon Map
wavelet2.c
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/*
=========================================================================
2-dimensional wavelet transform on (2^l) x (2^l) sized arrays of 3-tuples,
where l > 1.
Compile with -DWAVELET_TEST to build standalone unit tests.
Roland Schregle (roland.schregle@{hslu.ch, gmail.com})
(c) Lucerne University of Applied Sciences and Arts,
supported by the Swiss National Science Foundation
(SNSF #179067, "Light Fields for Spatio-Temporal Glare Assessment")
=========================================================================
$Id$
*/
#include "wavelet2.h"
#include <math.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#define min(a, b) ((a) < (b) ? (a) : (b))
#define coeffAvg(a) (((a) [0] + (a) [1] + (a) [2]) / 3)
#define coeffThresh(c, t) ( \
fabs((c) [0]) < (t) || fabs((c) [1]) < (t) || fabs((c) [2]) < (t) \
)
/* The following defs are const, but strict compilers pretend to be dumber
than they are, and refuse to init from a func (in this case sqrt(2)
and sqrt(3)), or other consts */
#define SQRT2 1.41421356
#define SQRT3 1.73205081
#define H4NORM (0.25 / SQRT2)
/* Haar wavelet coeffs */
static
const
WAVELET_COEFF
h2
=
1
/
SQRT2
;
/* Daubechies D4 wavelet coeffs */
static
const
WAVELET_COEFF
h4
[
4
]
=
{
H4NORM
*
(
1
+
SQRT3
),
H4NORM
*
(
3
+
SQRT3
),
H4NORM
*
(
3
-
SQRT3
),
H4NORM
*
(
1
-
SQRT3
)
};
static
const
WAVELET_COEFF
g4
[
4
]
=
{
H4NORM
*
(
1
-
SQRT3
),
-
H4NORM
*
(
3
-
SQRT3
),
H4NORM
*
(
3
+
SQRT3
),
-
H4NORM
*
(
1
+
SQRT3
)
};
/* g4 [4] = { h4 [3], -h4 [2], h4 [1], -h4 [0] }; */
WaveletMatrix
allocWaveletMatrix
(
unsigned
l
)
/*
Allocate and return a 2D coefficient array of size (2^l) x (2^l),
where l >= 1. Returns NULL if allocation failed.
*/
{
const
unsigned
len
=
1
<<
l
;
unsigned
i
;
WaveletMatrix
y
=
NULL
;
if
(
l
>=
1
)
{
if
(
!
(
y
=
calloc
(
len
,
sizeof
(
WaveletCoeff3
*
))))
return
NULL
;
for
(
i
=
0
;
i
<
len
;
i
++
)
if
(
!
(
y
[
i
]
=
calloc
(
len
,
WAVELET_COEFFSIZE
)))
return
NULL
;
}
return
y
;
}
void
freeWaveletMatrix
(
WaveletMatrix
y
,
unsigned
l
)
/*
Free previously allocated 2D coefficient array y of size (2^l) x (2^l)
*/
{
unsigned
i
,
j
;
const
unsigned
len
=
1
<<
l
;
if
(
y
)
{
for
(
i
=
0
;
i
<
len
;
i
++
)
free
(
y
[
i
]);
free
(
y
);
}
}
#ifdef WAVELET_DBG
static
void
zeroCoeffs
(
WaveletMatrix
y
,
unsigned
l
)
/* Zero output array to facilitate debugging */
{
const
unsigned
len
=
1
<<
l
;
unsigned
i
;
for
(
i
=
0
;
i
<
len
;
i
++
)
memset
(
y
[
i
],
0
,
len
*
WAVELET_COEFFSIZE
);
}
static
void
dumpCoeffs
(
const
WaveletMatrix
y
,
const
WaveletMatrix
yt
,
unsigned
l
,
float
thresh
)
/* Dump arrays y and yt side-by-side to stdout (skip yt if NULL) */
{
const
unsigned
len
=
1
<<
l
;
unsigned
i
,
j
,
k
;
for
(
i
=
0
;
i
<
len
;
i
++
)
{
for
(
j
=
0
;
j
<
len
;
j
++
)
printf
(
coeffThresh
(
y
[
i
][
j
],
thresh
)
&&
(
i
|
j
)
?
"[% 3.2f]
\t
"
:
" % 3.2f
\t
"
,
coeffAvg
(
y
[
i
][
j
])
);
if
(
yt
)
{
printf
(
" -->
\t
"
);
for
(
j
=
0
;
j
<
len
;
j
++
)
printf
(
"% 4.3f
\t
"
,
coeffAvg
(
yt
[
i
][
j
]));
}
putchar
(
'\n'
);
}
}
static
float
rmseCoeffs
(
const
WaveletMatrix
y1
,
const
WaveletMatrix
y2
,
unsigned
l
)
/* Calculate RMSE between matrices y and y0 */
{
const
unsigned
len
=
1
<<
l
;
unsigned
i
,
j
;
float
d
,
rmse
=
0
;
for
(
i
=
0
;
i
<
len
;
i
++
)
for
(
j
=
0
;
j
<
len
;
j
++
)
{
d
=
(
coeffAvg
(
y1
[
i
][
j
])
-
coeffAvg
(
y2
[
i
][
j
]))
/
coeffAvg
(
y1
[
i
][
j
]);
rmse
+=
d
*
d
;
}
return
sqrt
(
rmse
/
((
float
)
len
*
len
));
}
#endif
static
int
haarStep
(
WaveletMatrix
y
,
WaveletMatrix
yt
,
unsigned
l
)
/*
Single step of forward 2D Haar wavelet transform on array y of size
(2^l) x (2^l) containing 3-tuples, where l >= 1. The transform is
performed over y's 2nd axis (i.e. horizontally, assuming row-major
addressing as per C convention).
Note the triplets per array element are _not_ decorrelated, but
transformed independently.
The wavelet coefficients are returned in the *TRANSPOSED* output array
yt, of identical dimensions to y. The transpose arranges the generated
coefficients vertically, and prepares the array for another transform
over its 2nd axis in a subsequent call (this time as input y).
The result of a subsequent transform restores yt to y's original
orientation, in which case both horizontal and vertical axes have been
decorrelated.
Returns 0 on success, else -1.
*/
{
static
unsigned
axis
=
0
;
const
unsigned
len
=
1
<<
l
,
hlen
=
1
<<
(
l
-
1
);
unsigned
h
,
i
,
j
,
k
;
if
(
len
<
2
||
!
y
||
!
yt
)
/* Input shorter than wavelet support, or no input/output */
return
-
1
;
#ifdef WAVELET_DBG
zeroCoeffs
(
yt
,
l
);
#endif
/* NOTE: yt is transposed on the fly such that the next function call
* transforms over the alternate axis. This is done by simply swapping
* the indices during assignment */
for
(
i
=
0
;
i
<
len
;
i
++
)
{
for
(
j
=
0
;
j
<
len
;
j
+=
2
)
{
h
=
j
>>
1
;
for
(
k
=
0
;
k
<
3
;
k
++
)
{
/* Smooth/approx/avg/lowpass */
yt
[
h
]
[
i
]
[
k
]
=
h2
*
(
y
[
i
]
[
j
]
[
k
]
+
y
[
i
]
[
j
+
1
]
[
k
]
);
/* Detail/diff/highpass */
yt
[
hlen
+
h
]
[
i
]
[
k
]
=
h2
*
(
y
[
i
]
[
j
]
[
k
]
-
y
[
i
]
[
j
+
1
]
[
k
]
);
}
}
}
#ifdef WAVELET_DBG
printf
(
"%s FWD HAAR (%d x %d)
\n
"
,
axis
?
"VERT"
:
"HORIZ"
,
len
,
len
);
dumpCoeffs
(
y
,
yt
,
l
,
0
);
putchar
(
'\n'
);
axis
^=
1
;
#endif
return
0
;
}
static
int
haarInvStep
(
WaveletMatrix
y
,
WaveletMatrix
yt
,
unsigned
l
)
/*
Single step of inverse 2D Haar wavelet transform on coefficient array y
of size (2^l) x (2^l) containing 3-tuples, where l >= 1. This reverses
the forward transform above. The transform is inverted over y's 2nd axis
(i.e. horizontally, assuming row-major addressing as per C convention).
The inverted coefficients are returned in the *TRANSPOSED* output array
yt, of identical dimensions to y. The transpose arranges the inverted
coefficients vertically, and prepares the array for another inverse
transform over its 2nd axis in a subsequent call (this time as input y).
The result of a subsequent inverse transform restores yt to y's original
orientation, in which case both horizontal and vertical axes have been
inversely transformed.
Returns 0 on success, else -1.
*/
{
static
unsigned
axis
=
1
;
const
unsigned
len
=
1
<<
l
,
hlen
=
1
<<
(
l
-
1
);
unsigned
h
,
i
,
j
,
k
;
if
(
len
<
2
||
!
y
||
!
yt
)
/* Too few coeffs for reconstruction, or no input/output */
return
-
1
;
#ifdef WAVELET_DBG
zeroCoeffs
(
yt
,
l
);
#endif
/* NOTE: i, j are swapped relative to the forward transform, as axis
* order is now reversed. */
/* NOTE: yt is transposed on the fly such that the next function call
* inverts over the alternate axis. This is done by simply swapping
* the indices during assignment */
for
(
i
=
0
;
i
<
len
;
i
++
)
{
for
(
j
=
0
;
j
<
len
;
j
+=
2
)
{
h
=
j
>>
1
;
for
(
k
=
0
;
k
<
3
;
k
++
)
{
yt
[
i
]
[
j
]
[
k
]
=
h2
*
(
y
[
h
]
[
i
]
[
k
]
+
/* Avg */
y
[
hlen
+
h
]
[
i
]
[
k
]
/* Diff */
);
yt
[
i
]
[
j
+
1
]
[
k
]
=
h2
*
(
y
[
h
]
[
i
]
[
k
]
-
/* Avg */
y
[
hlen
+
h
]
[
i
]
[
k
]
/* Diff */
);
}
}
}
#ifdef WAVELET_DBG
printf
(
"%s INV HAAR (%d x %d)
\n
"
,
axis
?
"VERT"
:
"HORIZ"
,
len
,
len
);
dumpCoeffs
(
y
,
yt
,
l
,
0
);
putchar
(
'\n'
);
axis
^=
1
;
#endif
return
0
;
}
static
int
d4Step
(
WaveletMatrix
y
,
WaveletMatrix
yt
,
unsigned
l
)
/*
Single step of forward 2D Daubechies D4 wavelet transform on array y of
size (2^l) x (2^l) containing 3-tuples, where l >= 2. The transform is
performed over y's 2nd axis (i.e. horizontally, assuming row-major
addressing as per C convention).
Note the triplets per array element are _not_ decorrelated, but
transformed independently.
The wavelet coefficients are returned in the *TRANSPOSED* output array
yt, of identical dimensions to y. The transpose arranges the generated
coefficients vertically, and prepares the array for another transform
over its 2nd axis in a subsequent call (this time as input y).
The result of a subsequent transform restores yt to y's original
orientation, in which case both horizontal and vertical axes have been
decorrelated.
Returns 0 on success, else -1.
*/
{
static
unsigned
axis
=
0
;
const
unsigned
len
=
1
<<
l
,
hlen
=
1
<<
(
l
-
1
);
unsigned
h
,
i
,
j
,
k
;
if
(
len
<
4
||
!
y
||
!
yt
)
/* Input shorter than wavelet support, or no input/output */
return
-
1
;
#ifdef WAVELET_DBG
zeroCoeffs
(
yt
,
l
);
#endif
/* NOTE: yt is transposed on the fly such that the next function call
* transforms over the alternate axis. This is done by simply swapping
* the indices during assignment */
for
(
i
=
0
;
i
<
len
;
i
++
)
{
/* Transform until upper boundary */
for
(
j
=
0
;
j
<
len
-
2
;
j
+=
2
)
{
h
=
j
>>
1
;
for
(
k
=
0
;
k
<
3
;
k
++
)
{
/* Smooth/approx/avg/lowpass */
yt
[
h
]
[
i
]
[
k
]
=
h4
[
0
]
*
y
[
i
]
[
j
]
[
k
]
+
h4
[
1
]
*
y
[
i
]
[
j
+
1
]
[
k
]
+
h4
[
2
]
*
y
[
i
]
[
j
+
2
]
[
k
]
+
h4
[
3
]
*
y
[
i
]
[
j
+
3
]
[
k
];
/* Detail/diff/highpass */
yt
[
hlen
+
h
]
[
i
]
[
k
]
=
g4
[
0
]
*
y
[
i
]
[
j
]
[
k
]
+
g4
[
1
]
*
y
[
i
]
[
j
+
1
]
[
k
]
+
g4
[
2
]
*
y
[
i
]
[
j
+
2
]
[
k
]
+
g4
[
3
]
*
y
[
i
]
[
j
+
3
]
[
k
];
}
}
/* Transform at upper boundary with wraparound.
Note j is set to last index from previous loop */
h
=
j
>>
1
;
for
(
k
=
0
;
k
<
3
;
k
++
)
{
/* Smooth/approx/avg/lowpass */
yt
[
h
]
[
i
]
[
k
]
=
h4
[
0
]
*
y
[
i
]
[
j
]
[
k
]
+
h4
[
1
]
*
y
[
i
]
[
j
+
1
]
[
k
]
+
h4
[
2
]
*
y
[
i
]
[
0
]
[
k
]
+
h4
[
3
]
*
y
[
i
]
[
1
]
[
k
];
/* Detail/diff/highpass */
yt
[
hlen
+
h
]
[
i
]
[
k
]
=
g4
[
0
]
*
y
[
i
]
[
j
]
[
k
]
+
g4
[
1
]
*
y
[
i
]
[
j
+
1
]
[
k
]
+
g4
[
2
]
*
y
[
i
]
[
0
]
[
k
]
+
g4
[
3
]
*
y
[
i
]
[
1
]
[
k
];
}
}
#ifdef WAVELET_DBG
printf
(
"%s FWD D4 (%d x %d)
\n
"
,
axis
?
"VERT"
:
"HORIZ"
,
len
,
len
);
dumpCoeffs
(
y
,
yt
,
l
,
0
);
putchar
(
'\n'
);
axis
^=
1
;
#endif
return
0
;
}
static
int
d4InvStep
(
WaveletMatrix
y
,
WaveletMatrix
yt
,
unsigned
l
)
/*
Single step of inverse 2D Daubechies D4 wavelet transform on coefficient
array y of size (2^l) x (2^l) containing 3-tuples, where l >= 2. This
reverses the forward transform above. The transform is inverted over y's
2nd axis (i.e. horizontally, assuming row-major addressing as per C
convention).
The inverted coefficients are returned in the *TRANSPOSED* output array
yt, of identical dimensions to y. The transpose arranges the inverted
coefficients vertically, and prepares the array for another inverse
transform over its 2nd axis in a subsequent call (this time as input y).
The result of a subsequent inverse transform restores yt to y's original
orientation, in which case both horizontal and vertical axes have been
inversely transformed.
Returns 0 on success, else -1.
*/
{
static
unsigned
axis
=
1
;
const
unsigned
len
=
1
<<
l
,
hlen
=
1
<<
(
l
-
1
);
unsigned
h
,
i
,
j
,
k
;
if
(
len
<
4
||
!
y
||
!
yt
)
/* Too few coeffs for reconstruction, or no input/output */
return
-
1
;
#ifdef WAVELET_DBG
zeroCoeffs
(
yt
,
l
);
#endif
/* NOTE: i, j are swapped relative to the forward transform, as axis
* order is now reversed. */
/* NOTE: yt is transposed on the fly such that the next function call
* inverts over the alternate axis. This is done by simply swapping
* the indices during assignment */
for
(
i
=
0
;
i
<
len
;
i
++
)
{
/* Invert at lower boundary with wraparound */
for
(
k
=
0
;
k
<
3
;
k
++
)
{
yt
[
i
]
[
0
]
[
k
]
=
h4
[
2
]
*
y
[
hlen
-
1
]
[
i
]
[
k
]
+
/* Last avg */
g4
[
2
]
*
y
[
len
-
1
]
[
i
]
[
k
]
+
/* Last diff */
h4
[
0
]
*
y
[
0
]
[
i
]
[
k
]
+
/* First avg */
g4
[
0
]
*
y
[
hlen
]
[
i
]
[
k
];
/* First diff */
yt
[
i
]
[
1
]
[
k
]
=
h4
[
3
]
*
y
[
hlen
-
1
]
[
i
]
[
k
]
+
g4
[
3
]
*
y
[
len
-
1
]
[
i
]
[
k
]
+
h4
[
1
]
*
y
[
0
]
[
i
]
[
k
]
+
g4
[
1
]
*
y
[
hlen
]
[
i
]
[
k
];
}
/* Invert until upper boundary */
for
(
j
=
2
;
j
<
len
;
j
+=
2
)
{
h
=
(
j
>>
1
)
-
1
;
for
(
k
=
0
;
k
<
3
;
k
++
)
{
yt
[
i
]
[
j
]
[
k
]
=
h4
[
2
]
*
y
[
h
]
[
i
]
[
k
]
+
/* Avg */
g4
[
2
]
*
y
[
hlen
+
h
]
[
i
]
[
k
]
+
/* Diff */
h4
[
0
]
*
y
[
h
+
1
]
[
i
]
[
k
]
+
/* Next avg */
g4
[
0
]
*
y
[
hlen
+
h
+
1
]
[
i
]
[
k
];
/* Next diff */
yt
[
i
]
[
j
+
1
]
[
k
]
=
h4
[
3
]
*
y
[
h
]
[
i
]
[
k
]
+
g4
[
3
]
*
y
[
hlen
+
h
]
[
i
]
[
k
]
+
h4
[
1
]
*
y
[
h
+
1
]
[
i
]
[
k
]
+
g4
[
1
]
*
y
[
hlen
+
h
+
1
]
[
i
]
[
k
];
}
}
}
#ifdef WAVELET_DBG
printf
(
"%s INV D4 (%d x %d)
\n
"
,
axis
?
"VERT"
:
"HORIZ"
,
len
,
len
);
dumpCoeffs
(
y
,
yt
,
l
,
0
);
putchar
(
'\n'
);
axis
^=
1
;
#endif
return
0
;
}
int
waveletXform2
(
WaveletMatrix
y
,
WaveletMatrix
yt
,
unsigned
l
)
/*
Perform full 2D multiresolution forward wavelet transform on array y of
size (2^l) x (2^l) containing original signal as 3-tuples, where l >= 1.
Note no intra-tuple transform occurs.
The wavelet coefficients are returned in array y, containing the coarsest
approximation in y [0][0] followed by horizontal/vertical details in
order of increasing resolution/frequency.
A preallocated array yt of identical dimensions to y can be supplied as
buffer for intermediate results. If yt == NULL, a buffer is
automatically allocated and freed on demand, but this is inefficient for
frequent calls. It is recommended to preallocate yt to the maximum
expected size. The dimensions of yt are not checked; this is the
caller's responsibility.
Returns 0 on success, else -1.
*/
{
const
unsigned
len
=
1
<<
l
;
unsigned
li
;
WaveletMatrix
ytloc
=
NULL
;
/* Skip transform if input too short or missing */
if
(
l
<
1
||
!
y
)
return
-
1
;
if
(
!
yt
)
/* No buffer supplied; allocate one on demand */
if
(
!
(
yt
=
ytloc
=
allocWaveletMatrix
(
l
)))
{
fprintf
(
stderr
,
"ERROR - Failed allocating %dx%d buffer array"
" in WaveletXform2()"
,
len
,
len
);
return
-
1
;
}
for
(
li
=
l
;
li
>
1
;
li
--
)
{
/* Apply horizontal & vertical Daubechies D4 transform, swapping input
and transposed output array */
if
(
d4Step
(
y
,
yt
,
li
)
||
d4Step
(
yt
,
y
,
li
))
return
-
1
;
}
/* Apply horizontal & vertical Haar transform at coarsest resolution
(li==1) to obtain single approximation coefficient at y [0][0]; all
other coeffs are details. */
if
(
haarStep
(
y
,
yt
,
li
)
||
haarStep
(
yt
,
y
,
li
))
return
-
1
;
/* NOTE: All coefficients now in y */
if
(
ytloc
)
/* Free yt if allocated on demand */
freeWaveletMatrix
(
ytloc
,
l
);
return
0
;
}
int
waveletInvXform2
(
WaveletMatrix
y
,
WaveletMatrix
yt
,
unsigned
l
)
/*
Perform full 2D multiresolution inverse wavelet transform on array y of
size (2^l) x (2^l) containing wavelet coefficients as 3-tuples, where
l >= 1. Note no intra-tuple transform occurs.
A preallocated array yt of identical dimensions to y can be supplied as
buffer for intermediate results. If yt == NULL, a buffer is
automatically allocated and freed on demand, but this is inefficient for
frequent calls. It is recommended to preallocate yt to the maximum
expected size. The dimensions of yt are not checked; this is the
caller's responsibility.
The reconstructed signal is returned in array y.
Returns 0 on success, else -1.
*/
{
const
unsigned
len
=
1
<<
l
;
unsigned
li
;
WaveletMatrix
ytloc
=
NULL
;
/* Skip inverse transform if input too short or missing */
if
(
l
<
1
||
!
y
)
return
-
1
;
if
(
!
yt
)
/* No buffer supplied; allocate one on demand */
if
(
!
(
yt
=
ytloc
=
allocWaveletMatrix
(
l
)))
{
fprintf
(
stderr
,
"ERROR - Failed allocating %dx%d buffer array"
" in WaveletInvXform2()"
,
len
,
len
);
return
-
1
;
}
/* Invert horizontal & vertical Haar transform at coarsest level (li==1),
swapping input and transposed output array */
if
(
haarInvStep
(
y
,
yt
,
1
)
||
haarInvStep
(
yt
,
y
,
1
))
return
-
1
;
for
(
li
=
2
;
li
<=
l
;
li
++
)
{
/* Invert horizontal & vertical Daubechies D4 transform, swapping
input and transposed output arrays */
if
(
d4InvStep
(
y
,
yt
,
li
)
||
d4InvStep
(
yt
,
y
,
li
))
return
-
1
;
}
/* NOTE: Reconstructed signal now in y */
if
(
ytloc
)
/* Free yt if allocated on demand */
freeWaveletMatrix
(
ytloc
,
l
);
return
0
;
}
#ifdef WAVELET_TEST
#include <stdio.h>
int
main
(
int
argc
,
char
*
argv
[])
{
int
i
,
j
,
k
,
l
;
unsigned
len
,
numThresh
=
0
;
WaveletMatrix
y0
=
NULL
,
y
=
NULL
;
FILE
*
dataFile
=
NULL
;
float
inData
,
thresh
=
0
;
if
(
argc
<
2
)
{
fprintf
(
stderr
,
"%s <l> [threshold] [dataFile]
\n
"
,
argv
[
0
]);
fputs
(
"Missing array resolution l > 1, "
"compression threshold >= 0
\n
"
,
stderr
);
return
-
1
;
}
if
(
!
(
l
=
atoi
(
argv
[
1
]))
||
l
<
1
)
{
fputs
(
"Invalid array resolution l
\n
"
,
stderr
);
return
-
1
;
}
else
len
=
1
<<
l
;
if
(
argc
>
2
&&
(
thresh
=
atof
(
argv
[
2
]))
<
0
)
{
fprintf
(
stderr
,
"Invalid threshold %.3f
\n
"
,
thresh
);
return
-
1
;
}
/* Allocate arrays for original and reconstruction */
if
(
!
(
y0
=
allocWaveletMatrix
(
l
))
||
!
(
y
=
allocWaveletMatrix
(
l
)))
{
fprintf
(
stderr
,
"Failed allocating %dx%d array
\n
"
,
len
,
len
);
return
-
1
;
}
if
(
argc
>
3
)
{
/* Load data from file; length must not exceed allocated */
if
(
!
(
dataFile
=
fopen
(
argv
[
3
],
"r"
)))
{
fprintf
(
stderr
,
"Failed opening data file %s
\n
"
,
argv
[
3
]);
return
-
1
;
}
for
(
i
=
0
;
i
<
len
;
i
++
)
{
for
(
j
=
0
;
j
<
len
;
j
++
)
{
if
(
feof
(
dataFile
))
{
fprintf
(
stderr
,
"Premature end of file reading data from %s
\n
"
,
argv
[
2
]
);
fclose
(
dataFile
);
return
-
1
;
}
/* Read next float, skipping any leading whitespace */
if
(
fscanf
(
dataFile
,
" %f"
,
&
inData
))
{
y0
[
i
][
j
][
0
]
=
y0
[
i
][
j
][
1
]
=
y0
[
i
][
j
][
2
]
=
y
[
i
][
j
][
0
]
=
y
[
i
][
j
][
1
]
=
y
[
i
][
j
][
2
]
=
(
WAVELET_COEFF
)
inData
;
}
else
{
fprintf
(
stderr
,
"Error reading from data file %s
\n
"
,
argv
[
2
]
);
fclose
(
dataFile
);
return
-
1
;
}
}
}
fclose
(
dataFile
);
}
else
{
/* Init with random data */
srand48
(
111
);
for
(
i
=
0
;
i
<
len
;
i
++
)
for
(
j
=
0
;
j
<
len
;
j
++
)
#if 0
for (k = 0; k < 3; k++)
y0 [i][j][k] = y [i][j][k] = drand48();
#else
y0
[
i
][
j
][
0
]
=
y0
[
i
][
j
][
1
]
=
y0
[
i
][
j
][
2
]
=
y
[
i
][
j
][
0
]
=
y
[
i
][
j
][
1
]
=
y
[
i
][
j
][
2
]
=
drand48
();
#endif
}
/* Forward xform */
if
(
waveletXform2
(
y
,
NULL
,
l
))
{
fputs
(
"Forward xform failed
\n
"
,
stderr
);
return
-
1
;
}
/* Threshold coefficients; we use hard thresholding as it's easier
* to implement than soft thresholding, which requires sorting the
* coefficients */
/* NOTE: y [0][0] is omitted as it's the coarsest
* smooth/avg/approx/lowpass coefficient! */
for
(
i
=
0
;
i
<
len
;
i
++
)
for
(
j
=
0
;
j
<
len
;
j
++
)
{
if
(
coeffThresh
(
y
[
i
][
j
],
thresh
)
&&
(
i
|
j
))
{
y
[
i
][
j
][
0
]
=
y
[
i
][
j
][
1
]
=
y
[
i
][
j
][
2
]
=
0
;
numThresh
++
;
#if 0
/* Replace thresholded values with random noise in range
[-threshold, threshold] */
y [i][j][0] = y [i][j][1] = y [i][j][2] = thresh * (
2 * drand48() - 1
);
#endif
}
}
#ifdef WAVELET_DBG
/* Dump coefficients */
puts
(
"-----------------------------------------------------------
\n
"
);
if
(
numThresh
)
printf
(
"%d/%d coefficients thresholded
\n
"
,
numThresh
,
len
*
len
);
dumpCoeffs
(
y
,
NULL
,
l
,
thresh
);
puts
(
"
\n
-----------------------------------------------------------
\n
"
);
#endif
/* Inverse xform */
if
(
waveletInvXform2
(
y
,
NULL
,
l
))
{
fputs
(
"Inverse xform failed
\n
"
,
stderr
);
return
-
1
;
}
#ifdef WAVELET_DBG
puts
(
"-----------------------------------------------------------
\n
"
);
puts
(
"ORIG vs. INV XFORM"
);
dumpCoeffs
(
y0
,
y
,
l
,
0
);
#endif
printf
(
"
\n
Avg RMSE = %.2f
\n
"
,
rmseCoeffs
(
y0
,
y
,
l
));
freeWaveletMatrix
(
y0
,
l
);
freeWaveletMatrix
(
y
,
l
);
return
0
;
}
#endif
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