av1_txfm_test.cc: factorize 'dct_matrix'
Make it explicit that:
- forward tx is using the matrix
- inverse tx is using the transposed matrix
Change-Id: Ia9507f4f68397b07b6fd1868bb421bb9d5dd817d
diff --git a/test/av1_txfm_test.cc b/test/av1_txfm_test.cc
index a525cde..4545de1 100644
--- a/test/av1_txfm_test.cc
+++ b/test/av1_txfm_test.cc
@@ -66,24 +66,28 @@
double invSqrt2 = 1 / pow(2, 0.5);
+double dct_matrix(double n, double k, int size) {
+ return cos(M_PI * (2 * n + 1) * k / (2 * size));
+}
+
void reference_dct_1d(const double *in, double *out, int size) {
for (int k = 0; k < size; ++k) {
out[k] = 0;
for (int n = 0; n < size; ++n) {
- out[k] += in[n] * cos(M_PI * (2 * n + 1) * k / (2 * size));
+ out[k] += in[n] * dct_matrix(n, k, size);
}
if (k == 0) out[k] = out[k] * invSqrt2;
}
}
void reference_idct_1d(const double *in, double *out, int size) {
- for (int n = 0; n < size; ++n) {
- out[n] = 0;
- for (int k = 0; k < size; ++k) {
- if (k == 0)
- out[n] += invSqrt2 * in[k] * cos(M_PI * (2 * n + 1) * k / (2 * size));
+ for (int k = 0; k < size; ++k) {
+ out[k] = 0;
+ for (int n = 0; n < size; ++n) {
+ if (n == 0)
+ out[k] += invSqrt2 * in[n] * dct_matrix(k, n, size);
else
- out[n] += in[k] * cos(M_PI * (2 * n + 1) * k / (2 * size));
+ out[k] += in[n] * dct_matrix(k, n, size);
}
}
}
