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-rw-r--r--libavcodec/alpha/simple_idct_alpha.c303
1 files changed, 303 insertions, 0 deletions
diff --git a/libavcodec/alpha/simple_idct_alpha.c b/libavcodec/alpha/simple_idct_alpha.c
new file mode 100644
index 0000000000..3bd1b336fe
--- /dev/null
+++ b/libavcodec/alpha/simple_idct_alpha.c
@@ -0,0 +1,303 @@
+/*
+ * Simple IDCT (Alpha optimized)
+ *
+ * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * based upon some outcommented C code from mpeg2dec (idct_mmx.c
+ * written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>)
+ *
+ * Alpha optimizations by Måns Rullgård <mans@mansr.com>
+ * and Falk Hueffner <falk@debian.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "dsputil_alpha.h"
+#include "asm.h"
+
+// cos(i * M_PI / 16) * sqrt(2) * (1 << 14)
+// W4 is actually exactly 16384, but using 16383 works around
+// accumulating rounding errors for some encoders
+#define W1 22725
+#define W2 21407
+#define W3 19266
+#define W4 16383
+#define W5 12873
+#define W6 8867
+#define W7 4520
+#define ROW_SHIFT 11
+#define COL_SHIFT 20
+
+/* 0: all entries 0, 1: only first entry nonzero, 2: otherwise */
+static inline int idct_row(int16_t *row)
+{
+ int a0, a1, a2, a3, b0, b1, b2, b3, t;
+ uint64_t l, r, t2;
+ l = ldq(row);
+ r = ldq(row + 4);
+
+ if (l == 0 && r == 0)
+ return 0;
+
+ a0 = W4 * sextw(l) + (1 << (ROW_SHIFT - 1));
+
+ if (((l & ~0xffffUL) | r) == 0) {
+ a0 >>= ROW_SHIFT;
+ t2 = (uint16_t) a0;
+ t2 |= t2 << 16;
+ t2 |= t2 << 32;
+
+ stq(t2, row);
+ stq(t2, row + 4);
+ return 1;
+ }
+
+ a1 = a0;
+ a2 = a0;
+ a3 = a0;
+
+ t = extwl(l, 4); /* row[2] */
+ if (t != 0) {
+ t = sextw(t);
+ a0 += W2 * t;
+ a1 += W6 * t;
+ a2 -= W6 * t;
+ a3 -= W2 * t;
+ }
+
+ t = extwl(r, 0); /* row[4] */
+ if (t != 0) {
+ t = sextw(t);
+ a0 += W4 * t;
+ a1 -= W4 * t;
+ a2 -= W4 * t;
+ a3 += W4 * t;
+ }
+
+ t = extwl(r, 4); /* row[6] */
+ if (t != 0) {
+ t = sextw(t);
+ a0 += W6 * t;
+ a1 -= W2 * t;
+ a2 += W2 * t;
+ a3 -= W6 * t;
+ }
+
+ t = extwl(l, 2); /* row[1] */
+ if (t != 0) {
+ t = sextw(t);
+ b0 = W1 * t;
+ b1 = W3 * t;
+ b2 = W5 * t;
+ b3 = W7 * t;
+ } else {
+ b0 = 0;
+ b1 = 0;
+ b2 = 0;
+ b3 = 0;
+ }
+
+ t = extwl(l, 6); /* row[3] */
+ if (t) {
+ t = sextw(t);
+ b0 += W3 * t;
+ b1 -= W7 * t;
+ b2 -= W1 * t;
+ b3 -= W5 * t;
+ }
+
+
+ t = extwl(r, 2); /* row[5] */
+ if (t) {
+ t = sextw(t);
+ b0 += W5 * t;
+ b1 -= W1 * t;
+ b2 += W7 * t;
+ b3 += W3 * t;
+ }
+
+ t = extwl(r, 6); /* row[7] */
+ if (t) {
+ t = sextw(t);
+ b0 += W7 * t;
+ b1 -= W5 * t;
+ b2 += W3 * t;
+ b3 -= W1 * t;
+ }
+
+ row[0] = (a0 + b0) >> ROW_SHIFT;
+ row[1] = (a1 + b1) >> ROW_SHIFT;
+ row[2] = (a2 + b2) >> ROW_SHIFT;
+ row[3] = (a3 + b3) >> ROW_SHIFT;
+ row[4] = (a3 - b3) >> ROW_SHIFT;
+ row[5] = (a2 - b2) >> ROW_SHIFT;
+ row[6] = (a1 - b1) >> ROW_SHIFT;
+ row[7] = (a0 - b0) >> ROW_SHIFT;
+
+ return 2;
+}
+
+static inline void idct_col(int16_t *col)
+{
+ int a0, a1, a2, a3, b0, b1, b2, b3;
+
+ col[0] += (1 << (COL_SHIFT - 1)) / W4;
+
+ a0 = W4 * col[8 * 0];
+ a1 = W4 * col[8 * 0];
+ a2 = W4 * col[8 * 0];
+ a3 = W4 * col[8 * 0];
+
+ if (col[8 * 2]) {
+ a0 += W2 * col[8 * 2];
+ a1 += W6 * col[8 * 2];
+ a2 -= W6 * col[8 * 2];
+ a3 -= W2 * col[8 * 2];
+ }
+
+ if (col[8 * 4]) {
+ a0 += W4 * col[8 * 4];
+ a1 -= W4 * col[8 * 4];
+ a2 -= W4 * col[8 * 4];
+ a3 += W4 * col[8 * 4];
+ }
+
+ if (col[8 * 6]) {
+ a0 += W6 * col[8 * 6];
+ a1 -= W2 * col[8 * 6];
+ a2 += W2 * col[8 * 6];
+ a3 -= W6 * col[8 * 6];
+ }
+
+ if (col[8 * 1]) {
+ b0 = W1 * col[8 * 1];
+ b1 = W3 * col[8 * 1];
+ b2 = W5 * col[8 * 1];
+ b3 = W7 * col[8 * 1];
+ } else {
+ b0 = 0;
+ b1 = 0;
+ b2 = 0;
+ b3 = 0;
+ }
+
+ if (col[8 * 3]) {
+ b0 += W3 * col[8 * 3];
+ b1 -= W7 * col[8 * 3];
+ b2 -= W1 * col[8 * 3];
+ b3 -= W5 * col[8 * 3];
+ }
+
+ if (col[8 * 5]) {
+ b0 += W5 * col[8 * 5];
+ b1 -= W1 * col[8 * 5];
+ b2 += W7 * col[8 * 5];
+ b3 += W3 * col[8 * 5];
+ }
+
+ if (col[8 * 7]) {
+ b0 += W7 * col[8 * 7];
+ b1 -= W5 * col[8 * 7];
+ b2 += W3 * col[8 * 7];
+ b3 -= W1 * col[8 * 7];
+ }
+
+ col[8 * 0] = (a0 + b0) >> COL_SHIFT;
+ col[8 * 7] = (a0 - b0) >> COL_SHIFT;
+ col[8 * 1] = (a1 + b1) >> COL_SHIFT;
+ col[8 * 6] = (a1 - b1) >> COL_SHIFT;
+ col[8 * 2] = (a2 + b2) >> COL_SHIFT;
+ col[8 * 5] = (a2 - b2) >> COL_SHIFT;
+ col[8 * 3] = (a3 + b3) >> COL_SHIFT;
+ col[8 * 4] = (a3 - b3) >> COL_SHIFT;
+}
+
+/* If all rows but the first one are zero after row transformation,
+ all rows will be identical after column transformation. */
+static inline void idct_col2(int16_t *col)
+{
+ int i;
+ uint64_t l, r;
+
+ for (i = 0; i < 8; ++i) {
+ int a0 = col[i] + (1 << (COL_SHIFT - 1)) / W4;
+
+ a0 *= W4;
+ col[i] = a0 >> COL_SHIFT;
+ }
+
+ l = ldq(col + 0 * 4); r = ldq(col + 1 * 4);
+ stq(l, col + 2 * 4); stq(r, col + 3 * 4);
+ stq(l, col + 4 * 4); stq(r, col + 5 * 4);
+ stq(l, col + 6 * 4); stq(r, col + 7 * 4);
+ stq(l, col + 8 * 4); stq(r, col + 9 * 4);
+ stq(l, col + 10 * 4); stq(r, col + 11 * 4);
+ stq(l, col + 12 * 4); stq(r, col + 13 * 4);
+ stq(l, col + 14 * 4); stq(r, col + 15 * 4);
+}
+
+void ff_simple_idct_axp(int16_t *block)
+{
+
+ int i;
+ int rowsZero = 1; /* all rows except row 0 zero */
+ int rowsConstant = 1; /* all rows consist of a constant value */
+
+ for (i = 0; i < 8; i++) {
+ int sparseness = idct_row(block + 8 * i);
+
+ if (i > 0 && sparseness > 0)
+ rowsZero = 0;
+ if (sparseness == 2)
+ rowsConstant = 0;
+ }
+
+ if (rowsZero) {
+ idct_col2(block);
+ } else if (rowsConstant) {
+ idct_col(block);
+ for (i = 0; i < 8; i += 2) {
+ uint64_t v = (uint16_t) block[0];
+ uint64_t w = (uint16_t) block[8];
+
+ v |= v << 16;
+ w |= w << 16;
+ v |= v << 32;
+ w |= w << 32;
+ stq(v, block + 0 * 4);
+ stq(v, block + 1 * 4);
+ stq(w, block + 2 * 4);
+ stq(w, block + 3 * 4);
+ block += 4 * 4;
+ }
+ } else {
+ for (i = 0; i < 8; i++)
+ idct_col(block + i);
+ }
+}
+
+void ff_simple_idct_put_axp(uint8_t *dest, int line_size, int16_t *block)
+{
+ ff_simple_idct_axp(block);
+ put_pixels_clamped_axp_p(block, dest, line_size);
+}
+
+void ff_simple_idct_add_axp(uint8_t *dest, int line_size, int16_t *block)
+{
+ ff_simple_idct_axp(block);
+ add_pixels_clamped_axp_p(block, dest, line_size);
+}
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