/* * Simple IDCT (Alpha optimized) * * Copyright (c) 2001 Michael Niedermayer * * based upon some outcommented C code from mpeg2dec (idct_mmx.c * written by Aaron Holtzman ) * * Alpha optimizations by Måns Rullgård * and Falk Hueffner * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavcodec/dsputil.h" #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(DCTELEM *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(DCTELEM *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(DCTELEM *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(DCTELEM *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, DCTELEM *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, DCTELEM *block) { ff_simple_idct_axp(block); add_pixels_clamped_axp_p(block, dest, line_size); }