// CorrMultiBankStrideBLAS computes the strided correlation of
// a multi-channel image with a bank of multi-channel filters.
// h_p[u, v] = sum_q (f_q corr g_pq)[stride*u, stride*v]
func CorrMultiBankStrideBLAS(f *rimg64.Multi, g *MultiBank, stride int) (*rimg64.Multi, error) {
out := ValidSizeStride(f.Size(), g.Size(), stride)
if out.X <= 0 || out.Y <= 0 {
return nil, nil
}
h := rimg64.NewMulti(out.X, out.Y, len(g.Filters))
// Size of filters.
m, n, k := g.Width, g.Height, g.Channels
// Express as dense matrix multiplication.
// h_p[u, v] = sum_q (f_q corr g_pq)[u, v]
// h = A(f) X(g)
// where A is whk by mnk
// with w = ceil[(M-m+1)/stride],
// h = ceil[(N-n+1)/stride].
a := blas.NewMat(h.Width*h.Height, m*n*k)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
var s int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
for q := 0; q < g.Channels; q++ {
a.Set(r, s, f.At(stride*u+i, stride*v+j, q))
s++
}
}
}
r++
}
}
}
x := blas.NewMat(m*n*k, h.Channels)
{
var r int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
for q := 0; q < g.Channels; q++ {
for p := 0; p < h.Channels; p++ {
x.Set(r, p, g.Filters[p].At(i, j, q))
}
r++
}
}
}
}
y := blas.MatMul(1, a, x)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
for p := 0; p < h.Channels; p++ {
h.Set(u, v, p, y.At(r, p))
}
r++
}
}
}
return h, nil
}
// CorrBankBLAS computes the correlation of an image with a bank of filters.
// h_p[u, v] = (f corr g_p)[u, v]
func CorrBankBLAS(f *rimg64.Image, g *Bank) (*rimg64.Multi, error) {
out := ValidSize(f.Size(), g.Size())
if out.X <= 0 || out.Y <= 0 {
return nil, nil
}
// Express as dense matrix multiplication.
// h_p[u, v] = (f corr g_q)[u, v]
// Y(h) = A(f) X(g)
// If the number of output channels is k, then
// A is (M-m+1)(N-n+1) x mn and
// X is mn x k, so that
// Y is (M-m+1)(N-n+1) x k.
h := rimg64.NewMulti(out.X, out.Y, len(g.Filters))
m, n, k := g.Width, g.Height, len(g.Filters)
a := blas.NewMat(out.X*out.Y, m*n)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
var s int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
a.Set(r, s, f.At(i+u, j+v))
s++
}
}
r++
}
}
}
x := blas.NewMat(m*n, k)
{
var r int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
for p := 0; p < h.Channels; p++ {
x.Set(r, p, g.Filters[p].At(i, j))
}
r++
}
}
}
y := blas.MatMul(1, a, x)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
for p := 0; p < h.Channels; p++ {
h.Set(u, v, p, y.At(r, p))
}
r++
}
}
}
return h, nil
}
// CorrMultiStrideBLAS computes the strided correlation of
// a multi-channel image with a multi-channel filter.
// h[u, v] = sum_q (f_q corr g_q)[stride*u, stride*v]
func CorrMultiStrideBLAS(f, g *rimg64.Multi, stride int) (*rimg64.Image, error) {
out := ValidSizeStride(f.Size(), g.Size(), stride)
if out.X <= 0 || out.Y <= 0 {
return nil, nil
}
h := rimg64.New(out.X, out.Y)
// Size of filters.
m, n, k := g.Width, g.Height, g.Channels
// Express as dense matrix multiplication.
// h[u, v] = sum_q (f_q corr g_q)[stride*u, stride*v]
// y(h) = A(f) x(g)
// where A is wh by mnk
// with w = ceil[(M-m+1)/stride],
// h = ceil[(N-n+1)/stride].
a := blas.NewMat(h.Width*h.Height, m*n*k)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
var s int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
for q := 0; q < g.Channels; q++ {
a.Set(r, s, f.At(stride*u+i, stride*v+j, q))
s++
}
}
}
r++
}
}
}
x := blas.NewMat(m*n*k, 1)
{
var r int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
for q := 0; q < g.Channels; q++ {
x.Set(r, 0, g.At(i, j, q))
r++
}
}
}
}
y := blas.MatMul(1, a, x)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
h.Set(u, v, y.At(r, 0))
r++
}
}
}
return h, nil
}
// CorrBLAS computes the correlation of an image with a filter.
// h[u, v] = (f corr g)[u, v]
func CorrBLAS(f, g *rimg64.Image) (*rimg64.Image, error) {
out := ValidSize(f.Size(), g.Size())
if out.X <= 0 || out.Y <= 0 {
return nil, nil
}
h := rimg64.New(out.X, out.Y)
// Size of filters.
m, n := g.Width, g.Height
// Express as dense matrix multiplication.
// h[u, v] = (f corr g)[u, v]
// y(h) = A(f) x(g)
// where A is (M-m+1)(N-n+1) by mn.
a := blas.NewMat(h.Width*h.Height, m*n)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
var s int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
a.Set(r, s, f.At(u+i, v+j))
s++
}
}
r++
}
}
}
x := blas.NewMat(m*n, 1)
{
var r int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
x.Set(r, 0, g.At(i, j))
r++
}
}
}
y := blas.MatMul(1, a, x)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
h.Set(u, v, y.At(r, 0))
r++
}
}
}
return h, nil
}
func randMat(m, n int) *blas.Mat {
a := blas.NewMat(m, n)
for i := 0; i < m; i++ {
for j := 0; j < n; j++ {
a.Set(i, j, rand.NormFloat64())
}
}
return a
}
// CorrMultiBankBLAS computes the correlation of
// a multi-channel image with a bank of multi-channel filters.
// h_p[u, v] = sum_q (f_q corr g_pq)[u, v]
func CorrMultiBankBLAS(f *rimg64.Multi, g *MultiBank) (*rimg64.Multi, error) {
out := ValidSize(f.Size(), g.Size())
if out.X <= 0 || out.Y <= 0 {
return nil, nil
}
// Express as dense matrix multiplication.
// h_p[u, v] = sum_q (f_q corr g_pq)[u, v]
// Y(h) = A(f) X(g)
// If the number of input and output channels are Q and P, then
// A is (M-m+1)(N-n+1) x mnQ and
// X is mnQ x P, so that
// Y is (M-m+1)(N-n+1) x P.
// Note that the time to build the system is therefore
// affected more by the number of input channels Q than outputs P.
h := rimg64.NewMulti(out.X, out.Y, len(g.Filters))
M, N, K := h.Width, h.Height, h.Channels
m, n, k := g.Width, g.Height, g.Channels
a := blas.NewMat(M*N, m*n*k)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
var s int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
for q := 0; q < g.Channels; q++ {
a.Set(r, s, f.At(i+u, j+v, q))
s++
}
}
}
r++
}
}
}
x := blas.NewMat(m*n*k, K)
{
var r int
for i := 0; i < g.Width; i++ {
for j := 0; j < g.Height; j++ {
for q := 0; q < g.Channels; q++ {
for p := 0; p < h.Channels; p++ {
x.Set(r, p, g.Filters[p].At(i, j, q))
}
r++
}
}
}
}
y := blas.MatMul(1, a, x)
{
var r int
for u := 0; u < h.Width; u++ {
for v := 0; v < h.Height; v++ {
for p := 0; p < h.Channels; p++ {
h.Set(u, v, p, y.At(r, p))
}
r++
}
}
}
return h, nil
}