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Splits wavelet_mul into two parts. And fixes a lot of warnings.

master
Joshua Moerman 10 years ago
parent
a4bf3adb7d
commit
edd9a03456
1 changed files with 21 additions and 12 deletions
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  1. 33
      wavelet/wavelet2.hpp

33
wavelet/wavelet2.hpp
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@ -22,19 +22,28 @@ namespace wvlt{
return x[0] * coef[0] + x[stride] * coef[1] + x[2*stride] * coef[2] + x[3*stride] * coef[3];
}
// will overwrite x, x1 and x2 are next elements, or wrap around
// will calculate part of wavelete transform (in place!)
// size is size of vector x (so x[size-1] is valid)
inline void wavelet_mul(double* x, double x1, double x2, unsigned int size, unsigned int stride){
assert(is_pow_of_two(size) && is_pow_of_two(stride) && 4*stride <= size);
// does not calculate "last two" elements (it does not assume periodicity)
// calculates size/stride - 2 elements of the output
inline void wavelet_mul_base(double* x, unsigned int size, unsigned int stride){
assert(x && is_even(size) && is_pow_of_two(stride) && 4*stride <= size);
for(int i = 0; i < size - 2*stride; i += 2*stride){
for(unsigned int i = 0; i < size - 2*stride; i += 2*stride){
double y1 = inner_product(x + i, evn_coef, stride);
double y2 = inner_product(x + i, odd_coef, stride);
x[i] = y1;
x[i+stride] = y2;
}
}
// x1 and x2 are next elements, or wrap around
// calculates size/stride elements of the output
inline void wavelet_mul(double* x, double x1, double x2, unsigned int size, unsigned int stride){
assert(x && is_even(size) && is_pow_of_two(stride) && 4*stride <= size);
wavelet_mul_base(x, size, stride);
int i = size - 2*stride;
unsigned int i = size - 2*stride;
double y1 = x[i] * evn_coef[0] + x[i+stride] * evn_coef[1] + x1 * evn_coef[2] + x2 * evn_coef[3];
double y2 = x[i] * odd_coef[0] + x[i+stride] * odd_coef[1] + x1 * odd_coef[2] + x2 * odd_coef[3];
x[i] = y1;
@ -44,16 +53,16 @@ namespace wvlt{
// will overwrite x, x2 and x1 are previous elements, or wrap around
// size is size of vector x (so x[size-1] is valid)
inline void wavelet_inv(double* x, double x1, double x2, unsigned int size, unsigned int stride){
assert(is_pow_of_two(size) && is_pow_of_two(stride) && 4*stride <= size);
assert(x && is_even(size) && is_pow_of_two(stride) && 4*stride <= size);
for(int i = size - 2*stride; i >= 2*stride; i -= 2*stride){
for(unsigned int i = size - 2*stride; i >= 2*stride; i -= 2*stride){
double y1 = inner_product(x + i - 2*stride, evn_coef_inv, stride);
double y2 = inner_product(x + i - 2*stride, odd_coef_inv, stride);
x[i] = y1;
x[i+stride] = y2;
}
int i = 0;
unsigned int i = 0;
double y1 = x2 * evn_coef_inv[0] + x1 * evn_coef_inv[1] + x[i] * evn_coef_inv[2] + x[i+stride] * evn_coef_inv[3];
double y2 = x2 * odd_coef_inv[0] + x1 * odd_coef_inv[1] + x[i] * odd_coef_inv[2] + x[i+stride] * odd_coef_inv[3];
x[i] = y1;
@ -61,15 +70,15 @@ namespace wvlt{
}
inline void wavelet(double* x, unsigned int size){
assert(is_pow_of_two(size) && size >= 4);
for(int i = 1; i <= size / 4; i <<= 1){
assert(x && is_pow_of_two(size) && size >= 4);
for(unsigned int i = 1; i <= size / 4; i <<= 1){
wavelet_mul(x, x[0], x[i], size, i);
}
}
inline void unwavelet(double* x, unsigned int size){
assert(is_pow_of_two(size) && size >= 4);
for(int i = size / 4; i >= 1; i >>= 1){
assert(x && is_pow_of_two(size) && size >= 4);
for(unsigned int i = size / 4; i >= 1; i >>= 1){
wavelet_inv(x, x[size-i], x[size-2*i], size, i);
}
}