| Index: third_party/libjpeg/jfdctfst.c
|
| diff --git a/third_party/libjpeg/jfdctfst.c b/third_party/libjpeg/jfdctfst.c
|
| deleted file mode 100644
|
| index ccb378a3b45339e05167514a038cc2db616e8fe7..0000000000000000000000000000000000000000
|
| --- a/third_party/libjpeg/jfdctfst.c
|
| +++ /dev/null
|
| @@ -1,224 +0,0 @@
|
| -/*
|
| - * jfdctfst.c
|
| - *
|
| - * Copyright (C) 1994-1996, Thomas G. Lane.
|
| - * This file is part of the Independent JPEG Group's software.
|
| - * For conditions of distribution and use, see the accompanying README file.
|
| - *
|
| - * This file contains a fast, not so accurate integer implementation of the
|
| - * forward DCT (Discrete Cosine Transform).
|
| - *
|
| - * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT
|
| - * on each column. Direct algorithms are also available, but they are
|
| - * much more complex and seem not to be any faster when reduced to code.
|
| - *
|
| - * This implementation is based on Arai, Agui, and Nakajima's algorithm for
|
| - * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in
|
| - * Japanese, but the algorithm is described in the Pennebaker & Mitchell
|
| - * JPEG textbook (see REFERENCES section in file README). The following code
|
| - * is based directly on figure 4-8 in P&M.
|
| - * While an 8-point DCT cannot be done in less than 11 multiplies, it is
|
| - * possible to arrange the computation so that many of the multiplies are
|
| - * simple scalings of the final outputs. These multiplies can then be
|
| - * folded into the multiplications or divisions by the JPEG quantization
|
| - * table entries. The AA&N method leaves only 5 multiplies and 29 adds
|
| - * to be done in the DCT itself.
|
| - * The primary disadvantage of this method is that with fixed-point math,
|
| - * accuracy is lost due to imprecise representation of the scaled
|
| - * quantization values. The smaller the quantization table entry, the less
|
| - * precise the scaled value, so this implementation does worse with high-
|
| - * quality-setting files than with low-quality ones.
|
| - */
|
| -
|
| -#define JPEG_INTERNALS
|
| -#include "jinclude.h"
|
| -#include "jpeglib.h"
|
| -#include "jdct.h" /* Private declarations for DCT subsystem */
|
| -
|
| -#ifdef DCT_IFAST_SUPPORTED
|
| -
|
| -
|
| -/*
|
| - * This module is specialized to the case DCTSIZE = 8.
|
| - */
|
| -
|
| -#if DCTSIZE != 8
|
| - Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */
|
| -#endif
|
| -
|
| -
|
| -/* Scaling decisions are generally the same as in the LL&M algorithm;
|
| - * see jfdctint.c for more details. However, we choose to descale
|
| - * (right shift) multiplication products as soon as they are formed,
|
| - * rather than carrying additional fractional bits into subsequent additions.
|
| - * This compromises accuracy slightly, but it lets us save a few shifts.
|
| - * More importantly, 16-bit arithmetic is then adequate (for 8-bit samples)
|
| - * everywhere except in the multiplications proper; this saves a good deal
|
| - * of work on 16-bit-int machines.
|
| - *
|
| - * Again to save a few shifts, the intermediate results between pass 1 and
|
| - * pass 2 are not upscaled, but are represented only to integral precision.
|
| - *
|
| - * A final compromise is to represent the multiplicative constants to only
|
| - * 8 fractional bits, rather than 13. This saves some shifting work on some
|
| - * machines, and may also reduce the cost of multiplication (since there
|
| - * are fewer one-bits in the constants).
|
| - */
|
| -
|
| -#define CONST_BITS 8
|
| -
|
| -
|
| -/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus
|
| - * causing a lot of useless floating-point operations at run time.
|
| - * To get around this we use the following pre-calculated constants.
|
| - * If you change CONST_BITS you may want to add appropriate values.
|
| - * (With a reasonable C compiler, you can just rely on the FIX() macro...)
|
| - */
|
| -
|
| -#if CONST_BITS == 8
|
| -#define FIX_0_382683433 ((INT32) 98) /* FIX(0.382683433) */
|
| -#define FIX_0_541196100 ((INT32) 139) /* FIX(0.541196100) */
|
| -#define FIX_0_707106781 ((INT32) 181) /* FIX(0.707106781) */
|
| -#define FIX_1_306562965 ((INT32) 334) /* FIX(1.306562965) */
|
| -#else
|
| -#define FIX_0_382683433 FIX(0.382683433)
|
| -#define FIX_0_541196100 FIX(0.541196100)
|
| -#define FIX_0_707106781 FIX(0.707106781)
|
| -#define FIX_1_306562965 FIX(1.306562965)
|
| -#endif
|
| -
|
| -
|
| -/* We can gain a little more speed, with a further compromise in accuracy,
|
| - * by omitting the addition in a descaling shift. This yields an incorrectly
|
| - * rounded result half the time...
|
| - */
|
| -
|
| -#ifndef USE_ACCURATE_ROUNDING
|
| -#undef DESCALE
|
| -#define DESCALE(x,n) RIGHT_SHIFT(x, n)
|
| -#endif
|
| -
|
| -
|
| -/* Multiply a DCTELEM variable by an INT32 constant, and immediately
|
| - * descale to yield a DCTELEM result.
|
| - */
|
| -
|
| -#define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS))
|
| -
|
| -
|
| -/*
|
| - * Perform the forward DCT on one block of samples.
|
| - */
|
| -
|
| -GLOBAL(void)
|
| -jpeg_fdct_ifast (DCTELEM * data)
|
| -{
|
| - DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
|
| - DCTELEM tmp10, tmp11, tmp12, tmp13;
|
| - DCTELEM z1, z2, z3, z4, z5, z11, z13;
|
| - DCTELEM *dataptr;
|
| - int ctr;
|
| - SHIFT_TEMPS
|
| -
|
| - /* Pass 1: process rows. */
|
| -
|
| - dataptr = data;
|
| - for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
|
| - tmp0 = dataptr[0] + dataptr[7];
|
| - tmp7 = dataptr[0] - dataptr[7];
|
| - tmp1 = dataptr[1] + dataptr[6];
|
| - tmp6 = dataptr[1] - dataptr[6];
|
| - tmp2 = dataptr[2] + dataptr[5];
|
| - tmp5 = dataptr[2] - dataptr[5];
|
| - tmp3 = dataptr[3] + dataptr[4];
|
| - tmp4 = dataptr[3] - dataptr[4];
|
| -
|
| - /* Even part */
|
| -
|
| - tmp10 = tmp0 + tmp3; /* phase 2 */
|
| - tmp13 = tmp0 - tmp3;
|
| - tmp11 = tmp1 + tmp2;
|
| - tmp12 = tmp1 - tmp2;
|
| -
|
| - dataptr[0] = tmp10 + tmp11; /* phase 3 */
|
| - dataptr[4] = tmp10 - tmp11;
|
| -
|
| - z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */
|
| - dataptr[2] = tmp13 + z1; /* phase 5 */
|
| - dataptr[6] = tmp13 - z1;
|
| -
|
| - /* Odd part */
|
| -
|
| - tmp10 = tmp4 + tmp5; /* phase 2 */
|
| - tmp11 = tmp5 + tmp6;
|
| - tmp12 = tmp6 + tmp7;
|
| -
|
| - /* The rotator is modified from fig 4-8 to avoid extra negations. */
|
| - z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */
|
| - z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */
|
| - z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */
|
| - z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */
|
| -
|
| - z11 = tmp7 + z3; /* phase 5 */
|
| - z13 = tmp7 - z3;
|
| -
|
| - dataptr[5] = z13 + z2; /* phase 6 */
|
| - dataptr[3] = z13 - z2;
|
| - dataptr[1] = z11 + z4;
|
| - dataptr[7] = z11 - z4;
|
| -
|
| - dataptr += DCTSIZE; /* advance pointer to next row */
|
| - }
|
| -
|
| - /* Pass 2: process columns. */
|
| -
|
| - dataptr = data;
|
| - for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
|
| - tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];
|
| - tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];
|
| - tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];
|
| - tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];
|
| - tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];
|
| - tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];
|
| - tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];
|
| - tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];
|
| -
|
| - /* Even part */
|
| -
|
| - tmp10 = tmp0 + tmp3; /* phase 2 */
|
| - tmp13 = tmp0 - tmp3;
|
| - tmp11 = tmp1 + tmp2;
|
| - tmp12 = tmp1 - tmp2;
|
| -
|
| - dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */
|
| - dataptr[DCTSIZE*4] = tmp10 - tmp11;
|
| -
|
| - z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */
|
| - dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */
|
| - dataptr[DCTSIZE*6] = tmp13 - z1;
|
| -
|
| - /* Odd part */
|
| -
|
| - tmp10 = tmp4 + tmp5; /* phase 2 */
|
| - tmp11 = tmp5 + tmp6;
|
| - tmp12 = tmp6 + tmp7;
|
| -
|
| - /* The rotator is modified from fig 4-8 to avoid extra negations. */
|
| - z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */
|
| - z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */
|
| - z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */
|
| - z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */
|
| -
|
| - z11 = tmp7 + z3; /* phase 5 */
|
| - z13 = tmp7 - z3;
|
| -
|
| - dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */
|
| - dataptr[DCTSIZE*3] = z13 - z2;
|
| - dataptr[DCTSIZE*1] = z11 + z4;
|
| - dataptr[DCTSIZE*7] = z11 - z4;
|
| -
|
| - dataptr++; /* advance pointer to next column */
|
| - }
|
| -}
|
| -
|
| -#endif /* DCT_IFAST_SUPPORTED */
|
|
|