static void lrthresh(unsigned int D, const long dims[D], int llrblk, float lambda, unsigned int flags, complex float* out, const complex float* in)
{
long blkdims[MAX_LEV][D];
int levels = llr_blkdims(blkdims, ~flags, dims, llrblk);
UNUSED(levels);
const struct operator_p_s* p = lrthresh_create(dims, false, ~flags, (const long (*)[])blkdims, lambda, false, false);
operator_p_apply(p, 1., D, dims, out, D, dims, in);
operator_p_free(p);
}
void opt_reg_configure(unsigned int N, const long img_dims[N], struct opt_reg_s* ropts, const struct operator_p_s* prox_ops[NUM_REGS], const struct linop_s* trafos[NUM_REGS], unsigned int llr_blk, bool randshift, bool use_gpu)
{
float lambda = ropts->lambda;
if (-1. == lambda)
lambda = 0.;
// if no penalities specified but regularization
// parameter is given, add a l2 penalty
struct reg_s* regs = ropts->regs;
if ((0 == ropts->r) && (lambda > 0.)) {
regs[0].xform = L2IMG;
regs[0].xflags = 0u;
regs[0].jflags = 0u;
regs[0].lambda = lambda;
ropts->r = 1;
}
int nr_penalties = ropts->r;
long blkdims[MAX_LEV][DIMS];
int levels;
for (int nr = 0; nr < nr_penalties; nr++) {
// fix up regularization parameter
if (-1. == regs[nr].lambda)
regs[nr].lambda = lambda;
switch (regs[nr].xform) {
case L1WAV:
debug_printf(DP_INFO, "l1-wavelet regularization: %f\n", regs[nr].lambda);
if (0 != regs[nr].jflags)
debug_printf(DP_WARN, "joint l1-wavelet thresholding not currently supported.\n");
long minsize[DIMS] = { [0 ... DIMS - 1] = 1 };
minsize[0] = MIN(img_dims[0], 16);
minsize[1] = MIN(img_dims[1], 16);
minsize[2] = MIN(img_dims[2], 16);
unsigned int wflags = 0;
for (unsigned int i = 0; i < DIMS; i++) {
if ((1 < img_dims[i]) && MD_IS_SET(regs[nr].xflags, i)) {
wflags = MD_SET(wflags, i);
minsize[i] = MIN(img_dims[i], 16);
}
}
trafos[nr] = linop_identity_create(DIMS, img_dims);
prox_ops[nr] = prox_wavelet3_thresh_create(DIMS, img_dims, wflags, minsize, regs[nr].lambda, randshift);
break;
case TV:
debug_printf(DP_INFO, "TV regularization: %f\n", regs[nr].lambda);
trafos[nr] = linop_grad_create(DIMS, img_dims, regs[nr].xflags);
prox_ops[nr] = prox_thresh_create(DIMS + 1,
linop_codomain(trafos[nr])->dims,
regs[nr].lambda, regs[nr].jflags | MD_BIT(DIMS), use_gpu);
break;
case LLR:
debug_printf(DP_INFO, "lowrank regularization: %f\n", regs[nr].lambda);
// add locally lowrank penalty
levels = llr_blkdims(blkdims, regs[nr].jflags, img_dims, llr_blk);
assert(1 == levels);
assert(levels == img_dims[LEVEL_DIM]);
for(int l = 0; l < levels; l++)
#if 0
blkdims[l][MAPS_DIM] = img_dims[MAPS_DIM];
#else
blkdims[l][MAPS_DIM] = 1;
#endif
int remove_mean = 0;
trafos[nr] = linop_identity_create(DIMS, img_dims);
prox_ops[nr] = lrthresh_create(img_dims, randshift, regs[nr].xflags, (const long (*)[DIMS])blkdims, regs[nr].lambda, false, remove_mean, use_gpu);
break;
case MLR:
#if 0
// FIXME: multiscale low rank changes the output image dimensions
// and requires the forward linear operator. This should be decoupled...
debug_printf(DP_INFO, "multi-scale lowrank regularization: %f\n", regs[nr].lambda);
levels = multilr_blkdims(blkdims, regs[nr].jflags, img_dims, 8, 1);
img_dims[LEVEL_DIM] = levels;
max_dims[LEVEL_DIM] = levels;
for(int l = 0; l < levels; l++)
blkdims[l][MAPS_DIM] = 1;
trafos[nr] = linop_identity_create(DIMS, img_dims);
prox_ops[nr] = lrthresh_create(img_dims, randshift, regs[nr].xflags, (const long (*)[DIMS])blkdims, regs[nr].lambda, false, 0, use_gpu);
const struct linop_s* decom_op = sum_create( img_dims, use_gpu );
const struct linop_s* tmp_op = forward_op;
forward_op = linop_chain(decom_op, forward_op);
linop_free(decom_op);
linop_free(tmp_op);
#else
debug_printf(DP_WARN, "multi-scale lowrank regularization not yet supported: %f\n", regs[nr].lambda);
#endif
break;
case IMAGL1:
debug_printf(DP_INFO, "l1 regularization of imaginary part: %f\n", regs[nr].lambda);
trafos[nr] = linop_rdiag_create(DIMS, img_dims, 0, &(complex float){ 1.i });
prox_ops[nr] = prox_thresh_create(DIMS, img_dims, regs[nr].lambda, regs[nr].jflags, use_gpu);
break;
case IMAGL2:
debug_printf(DP_INFO, "l2 regularization of imaginary part: %f\n", regs[nr].lambda);
trafos[nr] = linop_rdiag_create(DIMS, img_dims, 0, &(complex float){ 1.i });
prox_ops[nr] = prox_leastsquares_create(DIMS, img_dims, regs[nr].lambda, NULL);
break;
case L1IMG:
debug_printf(DP_INFO, "l1 regularization: %f\n", regs[nr].lambda);
trafos[nr] = linop_identity_create(DIMS, img_dims);
prox_ops[nr] = prox_thresh_create(DIMS, img_dims, regs[nr].lambda, regs[nr].jflags, use_gpu);
break;
case L2IMG:
debug_printf(DP_INFO, "l2 regularization: %f\n", regs[nr].lambda);
trafos[nr] = linop_identity_create(DIMS, img_dims);
prox_ops[nr] = prox_leastsquares_create(DIMS, img_dims, regs[nr].lambda, NULL);
break;
case FTL1:
debug_printf(DP_INFO, "l1 regularization of Fourier transform: %f\n", regs[nr].lambda);
trafos[nr] = linop_fft_create(DIMS, img_dims, regs[nr].xflags);
prox_ops[nr] = prox_thresh_create(DIMS, img_dims, regs[nr].lambda, regs[nr].jflags, use_gpu);
break;
}
