| Index: jfdctint.c
|
| diff --git a/jfdctint.c b/jfdctint.c
|
| index 0a78b64aee8ffd7fc6c3469495ec577a59d44ed1..73e0b59032c90a1da7e2b8f9bfc0fd9593019587 100644
|
| --- a/jfdctint.c
|
| +++ b/jfdctint.c
|
| @@ -1,9 +1,12 @@
|
| /*
|
| * jfdctint.c
|
| *
|
| + * This file was part of the Independent JPEG Group's software.
|
| * Copyright (C) 1991-1996, 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.
|
| + * libjpeg-turbo Modifications:
|
| + * Copyright (C) 2015, D. R. Commander
|
| + * For conditions of distribution and use, see the accompanying README.ijg
|
| + * file.
|
| *
|
| * This file contains a slow-but-accurate integer implementation of the
|
| * forward DCT (Discrete Cosine Transform).
|
| @@ -26,7 +29,7 @@
|
| #define JPEG_INTERNALS
|
| #include "jinclude.h"
|
| #include "jpeglib.h"
|
| -#include "jdct.h" /* Private declarations for DCT subsystem */
|
| +#include "jdct.h" /* Private declarations for DCT subsystem */
|
|
|
| #ifdef DCT_ISLOW_SUPPORTED
|
|
|
| @@ -67,7 +70,7 @@
|
| * they are represented to better-than-integral precision. These outputs
|
| * require BITS_IN_JSAMPLE + PASS1_BITS + 3 bits; this fits in a 16-bit word
|
| * with the recommended scaling. (For 12-bit sample data, the intermediate
|
| - * array is INT32 anyway.)
|
| + * array is JLONG anyway.)
|
| *
|
| * To avoid overflow of the 32-bit intermediate results in pass 2, we must
|
| * have BITS_IN_JSAMPLE + CONST_BITS + PASS1_BITS <= 26. Error analysis
|
| @@ -79,7 +82,7 @@
|
| #define PASS1_BITS 2
|
| #else
|
| #define CONST_BITS 13
|
| -#define PASS1_BITS 1 /* lose a little precision to avoid overflow */
|
| +#define PASS1_BITS 1 /* lose a little precision to avoid overflow */
|
| #endif
|
|
|
| /* Some C compilers fail to reduce "FIX(constant)" at compile time, thus
|
| @@ -90,18 +93,18 @@
|
| */
|
|
|
| #if CONST_BITS == 13
|
| -#define FIX_0_298631336 ((INT32) 2446) /* FIX(0.298631336) */
|
| -#define FIX_0_390180644 ((INT32) 3196) /* FIX(0.390180644) */
|
| -#define FIX_0_541196100 ((INT32) 4433) /* FIX(0.541196100) */
|
| -#define FIX_0_765366865 ((INT32) 6270) /* FIX(0.765366865) */
|
| -#define FIX_0_899976223 ((INT32) 7373) /* FIX(0.899976223) */
|
| -#define FIX_1_175875602 ((INT32) 9633) /* FIX(1.175875602) */
|
| -#define FIX_1_501321110 ((INT32) 12299) /* FIX(1.501321110) */
|
| -#define FIX_1_847759065 ((INT32) 15137) /* FIX(1.847759065) */
|
| -#define FIX_1_961570560 ((INT32) 16069) /* FIX(1.961570560) */
|
| -#define FIX_2_053119869 ((INT32) 16819) /* FIX(2.053119869) */
|
| -#define FIX_2_562915447 ((INT32) 20995) /* FIX(2.562915447) */
|
| -#define FIX_3_072711026 ((INT32) 25172) /* FIX(3.072711026) */
|
| +#define FIX_0_298631336 ((JLONG) 2446) /* FIX(0.298631336) */
|
| +#define FIX_0_390180644 ((JLONG) 3196) /* FIX(0.390180644) */
|
| +#define FIX_0_541196100 ((JLONG) 4433) /* FIX(0.541196100) */
|
| +#define FIX_0_765366865 ((JLONG) 6270) /* FIX(0.765366865) */
|
| +#define FIX_0_899976223 ((JLONG) 7373) /* FIX(0.899976223) */
|
| +#define FIX_1_175875602 ((JLONG) 9633) /* FIX(1.175875602) */
|
| +#define FIX_1_501321110 ((JLONG) 12299) /* FIX(1.501321110) */
|
| +#define FIX_1_847759065 ((JLONG) 15137) /* FIX(1.847759065) */
|
| +#define FIX_1_961570560 ((JLONG) 16069) /* FIX(1.961570560) */
|
| +#define FIX_2_053119869 ((JLONG) 16819) /* FIX(2.053119869) */
|
| +#define FIX_2_562915447 ((JLONG) 20995) /* FIX(2.562915447) */
|
| +#define FIX_3_072711026 ((JLONG) 25172) /* FIX(3.072711026) */
|
| #else
|
| #define FIX_0_298631336 FIX(0.298631336)
|
| #define FIX_0_390180644 FIX(0.390180644)
|
| @@ -118,7 +121,7 @@
|
| #endif
|
|
|
|
|
| -/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result.
|
| +/* Multiply an JLONG variable by an JLONG constant to yield an JLONG result.
|
| * For 8-bit samples with the recommended scaling, all the variable
|
| * and constant values involved are no more than 16 bits wide, so a
|
| * 16x16->32 bit multiply can be used instead of a full 32x32 multiply.
|
| @@ -137,11 +140,11 @@
|
| */
|
|
|
| GLOBAL(void)
|
| -jpeg_fdct_islow (DCTELEM * data)
|
| +jpeg_fdct_islow (DCTELEM *data)
|
| {
|
| - INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
|
| - INT32 tmp10, tmp11, tmp12, tmp13;
|
| - INT32 z1, z2, z3, z4, z5;
|
| + JLONG tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
|
| + JLONG tmp10, tmp11, tmp12, tmp13;
|
| + JLONG z1, z2, z3, z4, z5;
|
| DCTELEM *dataptr;
|
| int ctr;
|
| SHIFT_TEMPS
|
| @@ -160,36 +163,36 @@ jpeg_fdct_islow (DCTELEM * data)
|
| tmp5 = dataptr[2] - dataptr[5];
|
| tmp3 = dataptr[3] + dataptr[4];
|
| tmp4 = dataptr[3] - dataptr[4];
|
| -
|
| +
|
| /* Even part per LL&M figure 1 --- note that published figure is faulty;
|
| * rotator "sqrt(2)*c1" should be "sqrt(2)*c6".
|
| */
|
| -
|
| +
|
| tmp10 = tmp0 + tmp3;
|
| tmp13 = tmp0 - tmp3;
|
| tmp11 = tmp1 + tmp2;
|
| tmp12 = tmp1 - tmp2;
|
| -
|
| - dataptr[0] = (DCTELEM) ((tmp10 + tmp11) << PASS1_BITS);
|
| - dataptr[4] = (DCTELEM) ((tmp10 - tmp11) << PASS1_BITS);
|
| -
|
| +
|
| + dataptr[0] = (DCTELEM) LEFT_SHIFT(tmp10 + tmp11, PASS1_BITS);
|
| + dataptr[4] = (DCTELEM) LEFT_SHIFT(tmp10 - tmp11, PASS1_BITS);
|
| +
|
| z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100);
|
| dataptr[2] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp13, FIX_0_765366865),
|
| - CONST_BITS-PASS1_BITS);
|
| + CONST_BITS-PASS1_BITS);
|
| dataptr[6] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp12, - FIX_1_847759065),
|
| - CONST_BITS-PASS1_BITS);
|
| -
|
| + CONST_BITS-PASS1_BITS);
|
| +
|
| /* Odd part per figure 8 --- note paper omits factor of sqrt(2).
|
| * cK represents cos(K*pi/16).
|
| * i0..i3 in the paper are tmp4..tmp7 here.
|
| */
|
| -
|
| +
|
| z1 = tmp4 + tmp7;
|
| z2 = tmp5 + tmp6;
|
| z3 = tmp4 + tmp6;
|
| z4 = tmp5 + tmp7;
|
| z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */
|
| -
|
| +
|
| tmp4 = MULTIPLY(tmp4, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
|
| tmp5 = MULTIPLY(tmp5, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
|
| tmp6 = MULTIPLY(tmp6, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
|
| @@ -198,16 +201,16 @@ jpeg_fdct_islow (DCTELEM * data)
|
| z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
|
| z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
|
| z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
|
| -
|
| +
|
| z3 += z5;
|
| z4 += z5;
|
| -
|
| +
|
| dataptr[7] = (DCTELEM) DESCALE(tmp4 + z1 + z3, CONST_BITS-PASS1_BITS);
|
| dataptr[5] = (DCTELEM) DESCALE(tmp5 + z2 + z4, CONST_BITS-PASS1_BITS);
|
| dataptr[3] = (DCTELEM) DESCALE(tmp6 + z2 + z3, CONST_BITS-PASS1_BITS);
|
| dataptr[1] = (DCTELEM) DESCALE(tmp7 + z1 + z4, CONST_BITS-PASS1_BITS);
|
| -
|
| - dataptr += DCTSIZE; /* advance pointer to next row */
|
| +
|
| + dataptr += DCTSIZE; /* advance pointer to next row */
|
| }
|
|
|
| /* Pass 2: process columns.
|
| @@ -225,36 +228,36 @@ jpeg_fdct_islow (DCTELEM * data)
|
| tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];
|
| tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];
|
| tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];
|
| -
|
| +
|
| /* Even part per LL&M figure 1 --- note that published figure is faulty;
|
| * rotator "sqrt(2)*c1" should be "sqrt(2)*c6".
|
| */
|
| -
|
| +
|
| tmp10 = tmp0 + tmp3;
|
| tmp13 = tmp0 - tmp3;
|
| tmp11 = tmp1 + tmp2;
|
| tmp12 = tmp1 - tmp2;
|
| -
|
| +
|
| dataptr[DCTSIZE*0] = (DCTELEM) DESCALE(tmp10 + tmp11, PASS1_BITS);
|
| dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(tmp10 - tmp11, PASS1_BITS);
|
| -
|
| +
|
| z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100);
|
| dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp13, FIX_0_765366865),
|
| - CONST_BITS+PASS1_BITS);
|
| + CONST_BITS+PASS1_BITS);
|
| dataptr[DCTSIZE*6] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp12, - FIX_1_847759065),
|
| - CONST_BITS+PASS1_BITS);
|
| -
|
| + CONST_BITS+PASS1_BITS);
|
| +
|
| /* Odd part per figure 8 --- note paper omits factor of sqrt(2).
|
| * cK represents cos(K*pi/16).
|
| * i0..i3 in the paper are tmp4..tmp7 here.
|
| */
|
| -
|
| +
|
| z1 = tmp4 + tmp7;
|
| z2 = tmp5 + tmp6;
|
| z3 = tmp4 + tmp6;
|
| z4 = tmp5 + tmp7;
|
| z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */
|
| -
|
| +
|
| tmp4 = MULTIPLY(tmp4, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
|
| tmp5 = MULTIPLY(tmp5, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
|
| tmp6 = MULTIPLY(tmp6, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
|
| @@ -263,20 +266,20 @@ jpeg_fdct_islow (DCTELEM * data)
|
| z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
|
| z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
|
| z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
|
| -
|
| +
|
| z3 += z5;
|
| z4 += z5;
|
| -
|
| +
|
| dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp4 + z1 + z3,
|
| - CONST_BITS+PASS1_BITS);
|
| + CONST_BITS+PASS1_BITS);
|
| dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp5 + z2 + z4,
|
| - CONST_BITS+PASS1_BITS);
|
| + CONST_BITS+PASS1_BITS);
|
| dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp6 + z2 + z3,
|
| - CONST_BITS+PASS1_BITS);
|
| + CONST_BITS+PASS1_BITS);
|
| dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp7 + z1 + z4,
|
| - CONST_BITS+PASS1_BITS);
|
| -
|
| - dataptr++; /* advance pointer to next column */
|
| + CONST_BITS+PASS1_BITS);
|
| +
|
| + dataptr++; /* advance pointer to next column */
|
| }
|
| }
|
|
|
|
|