ref: 7630cf0c3fe44b450eeec137d9ac09796c4ef29b
parent: 1d60b6bcb5f1d92c29a753def152106a76060689
parent: aa295918ed93abb5875e3ba956c0053f5b5acbfc
author: Yunqing Wang <yunqingwang@google.com>
date: Tue Feb 12 10:52:31 EST 2013
Merge "Rewrote fdct8x8" into experimental
--- a/vp9/encoder/vp9_dct.c
+++ b/vp9/encoder/vp9_dct.c
@@ -323,6 +323,8 @@
};
#endif
+#define NEW_FDCT8x8 1
+#if !NEW_FDCT8x8
static const int xC1S7 = 16069;
static const int xC2S6 = 15137;
static const int xC3S5 = 13623;
@@ -560,6 +562,7 @@
op++;
}
}
+#endif
void vp9_short_fhaar2x2_c(short *input, short *output, int pitch) {/* [1 1; 1 -1] orthogonal transform */
@@ -835,6 +838,79 @@
vp9_short_fdct4x4_c(input, output, pitch);
vp9_short_fdct4x4_c(input + 4, output + 16, pitch);
}
+
+#if NEW_FDCT8x8
+static void fdct8_1d(int16_t *input, int16_t *output) {+ int16_t step[8];
+ int temp1, temp2;
+
+ // stage 1
+ step[0] = input[0] + input[7];
+ step[1] = input[1] + input[6];
+ step[2] = input[2] + input[5];
+ step[3] = input[3] + input[4];
+ step[4] = input[3] - input[4];
+ step[5] = input[2] - input[5];
+ step[6] = input[1] - input[6];
+ step[7] = input[0] - input[7];
+
+ fdct4_1d(step, step);
+
+ // Stage 2
+ output[4] = step[4];
+ temp1 = (-step[5] + step[6]) * cospi_16_64;
+ temp2 = (step[6] + step[5]) * cospi_16_64;
+ output[5] = dct_const_round_shift(temp1);
+ output[6] = dct_const_round_shift(temp2);
+ output[7] = step[7];
+
+ // Stage 3
+ step[4] = output[4] + output[5];
+ step[5] = -output[5] + output[4];
+ step[6] = -output[6] + output[7];
+ step[7] = output[7] + output[6];
+
+ // Stage 4
+ output[0] = step[0];
+ output[4] = step[2];
+ output[2] = step[1];
+ output[6] = step[3];
+
+ temp1 = step[4] * cospi_28_64 + step[7] * cospi_4_64;
+ temp2 = step[5] * cospi_12_64 + step[6] * cospi_20_64;
+ output[1] = dct_const_round_shift(temp1);
+ output[5] = dct_const_round_shift(temp2);
+ temp1 = step[6] * cospi_12_64 + step[5] * -cospi_20_64;
+ temp2 = step[7] * cospi_28_64 + step[4] * -cospi_4_64;
+ output[3] = dct_const_round_shift(temp1);
+ output[7] = dct_const_round_shift(temp2);
+}
+
+void vp9_short_fdct8x8_c(int16_t *input, int16_t *output, int pitch) {+ int shortpitch = pitch >> 1;
+ int i, j;
+ int16_t out[64];
+ int16_t temp_in[8], temp_out[8];
+
+ // First transform columns
+ for (i = 0; i < 8; i++) {+ for (j = 0; j < 8; j++)
+ temp_in[j] = input[j * shortpitch + i] << 2;
+ fdct8_1d(temp_in, temp_out);
+ for (j = 0; j < 8; j++)
+ out[j * 8 + i] = temp_out[j];
+ }
+
+ // Then transform rows
+ for (i = 0; i < 8; ++i) {+ for (j = 0; j < 8; ++j)
+ temp_in[j] = out[j + i * 8];
+ fdct8_1d(temp_in, temp_out);
+ for (j = 0; j < 8; ++j)
+ output[j + i * 8] = temp_out[j] >> 1;
+ }
+}
+#endif
void vp9_short_walsh4x4_c(short *input, short *output, int pitch) {int i;