* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1994-1998, Thomas G. Lane.
* libjpeg-turbo Modifications:
- * Copyright (C) 2015, D. R. Commander.
+ * Copyright (C) 2015, 2022, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
* The dequantized coefficients are not integers because the AA&N scaling
* factors have been incorporated. We represent them scaled up by PASS1_BITS,
* so that the first and second IDCT rounds have the same input scaling.
- * For 8-bit JSAMPLEs, we choose IFAST_SCALE_BITS = PASS1_BITS so as to
+ * For 8-bit samples, we choose IFAST_SCALE_BITS = PASS1_BITS so as to
* avoid a descaling shift; this compromises accuracy rather drastically
* for small quantization table entries, but it saves a lot of shifts.
- * For 12-bit JSAMPLEs, there's no hope of using 16x16 multiplies anyway,
+ * For 12-bit samples, there's no hope of using 16x16 multiplies anyway,
* so we use a much larger scaling factor to preserve accuracy.
*
* A final compromise is to represent the multiplicative constants to only
*/
#if CONST_BITS == 8
-#define FIX_1_082392200 ((JLONG) 277) /* FIX(1.082392200) */
-#define FIX_1_414213562 ((JLONG) 362) /* FIX(1.414213562) */
-#define FIX_1_847759065 ((JLONG) 473) /* FIX(1.847759065) */
-#define FIX_2_613125930 ((JLONG) 669) /* FIX(2.613125930) */
+#define FIX_1_082392200 ((JLONG)277) /* FIX(1.082392200) */
+#define FIX_1_414213562 ((JLONG)362) /* FIX(1.414213562) */
+#define FIX_1_847759065 ((JLONG)473) /* FIX(1.847759065) */
+#define FIX_2_613125930 ((JLONG)669) /* FIX(2.613125930) */
#else
#define FIX_1_082392200 FIX(1.082392200)
#define FIX_1_414213562 FIX(1.414213562)
#ifndef USE_ACCURATE_ROUNDING
#undef DESCALE
-#define DESCALE(x,n) RIGHT_SHIFT(x, n)
+#define DESCALE(x, n) RIGHT_SHIFT(x, n)
#endif
* descale to yield a DCTELEM result.
*/
-#define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS))
+#define MULTIPLY(var, const) ((DCTELEM)DESCALE((var) * (const), CONST_BITS))
/* Dequantize a coefficient by multiplying it by the multiplier-table
*/
#if BITS_IN_JSAMPLE == 8
-#define DEQUANTIZE(coef,quantval) (((IFAST_MULT_TYPE) (coef)) * (quantval))
+#define DEQUANTIZE(coef, quantval) (((IFAST_MULT_TYPE)(coef)) * (quantval))
#else
-#define DEQUANTIZE(coef,quantval) \
- DESCALE((coef)*(quantval), IFAST_SCALE_BITS-PASS1_BITS)
+#define DEQUANTIZE(coef, quantval) \
+ DESCALE((coef) * (quantval), IFAST_SCALE_BITS - PASS1_BITS)
#endif
#else
#define DCTELEMBITS 32 /* DCTELEM must be 32 bits */
#endif
-#define IRIGHT_SHIFT(x,shft) \
- ((ishift_temp = (x)) < 0 ? \
- (ishift_temp >> (shft)) | ((~((DCTELEM) 0)) << (DCTELEMBITS-(shft))) : \
- (ishift_temp >> (shft)))
+#define IRIGHT_SHIFT(x, shft) \
+ ((ishift_temp = (x)) < 0 ? \
+ (ishift_temp >> (shft)) | ((~((DCTELEM)0)) << (DCTELEMBITS - (shft))) : \
+ (ishift_temp >> (shft)))
#else
#define ISHIFT_TEMPS
-#define IRIGHT_SHIFT(x,shft) ((x) >> (shft))
+#define IRIGHT_SHIFT(x, shft) ((x) >> (shft))
#endif
#ifdef USE_ACCURATE_ROUNDING
-#define IDESCALE(x,n) ((int) IRIGHT_SHIFT((x) + (1 << ((n)-1)), n))
+#define IDESCALE(x, n) ((int)IRIGHT_SHIFT((x) + (1 << ((n) - 1)), n))
#else
-#define IDESCALE(x,n) ((int) IRIGHT_SHIFT(x, n))
+#define IDESCALE(x, n) ((int)IRIGHT_SHIFT(x, n))
#endif
*/
GLOBAL(void)
-jpeg_idct_ifast (j_decompress_ptr cinfo, jpeg_component_info *compptr,
- JCOEFPTR coef_block,
- JSAMPARRAY output_buf, JDIMENSION output_col)
+_jpeg_idct_ifast(j_decompress_ptr cinfo, jpeg_component_info *compptr,
+ JCOEFPTR coef_block, _JSAMPARRAY output_buf,
+ JDIMENSION output_col)
{
DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
DCTELEM tmp10, tmp11, tmp12, tmp13;
JCOEFPTR inptr;
IFAST_MULT_TYPE *quantptr;
int *wsptr;
- JSAMPROW outptr;
- JSAMPLE *range_limit = IDCT_range_limit(cinfo);
+ _JSAMPROW outptr;
+ _JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[DCTSIZE2]; /* buffers data between passes */
SHIFT_TEMPS /* for DESCALE */
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
- quantptr = (IFAST_MULT_TYPE *) compptr->dct_table;
+ quantptr = (IFAST_MULT_TYPE *)compptr->dct_table;
wsptr = workspace;
for (ctr = DCTSIZE; ctr > 0; ctr--) {
/* Due to quantization, we will usually find that many of the input
* column DCT calculations can be simplified this way.
*/
- if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
- inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
- inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
- inptr[DCTSIZE*7] == 0) {
+ if (inptr[DCTSIZE * 1] == 0 && inptr[DCTSIZE * 2] == 0 &&
+ inptr[DCTSIZE * 3] == 0 && inptr[DCTSIZE * 4] == 0 &&
+ inptr[DCTSIZE * 5] == 0 && inptr[DCTSIZE * 6] == 0 &&
+ inptr[DCTSIZE * 7] == 0) {
/* AC terms all zero */
- int dcval = (int) DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
+ int dcval = (int)DEQUANTIZE(inptr[DCTSIZE * 0], quantptr[DCTSIZE * 0]);
- wsptr[DCTSIZE*0] = dcval;
- wsptr[DCTSIZE*1] = dcval;
- wsptr[DCTSIZE*2] = dcval;
- wsptr[DCTSIZE*3] = dcval;
- wsptr[DCTSIZE*4] = dcval;
- wsptr[DCTSIZE*5] = dcval;
- wsptr[DCTSIZE*6] = dcval;
- wsptr[DCTSIZE*7] = dcval;
+ wsptr[DCTSIZE * 0] = dcval;
+ wsptr[DCTSIZE * 1] = dcval;
+ wsptr[DCTSIZE * 2] = dcval;
+ wsptr[DCTSIZE * 3] = dcval;
+ wsptr[DCTSIZE * 4] = dcval;
+ wsptr[DCTSIZE * 5] = dcval;
+ wsptr[DCTSIZE * 6] = dcval;
+ wsptr[DCTSIZE * 7] = dcval;
inptr++; /* advance pointers to next column */
quantptr++;
/* Even part */
- tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
- tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
- tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
- tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
+ tmp0 = DEQUANTIZE(inptr[DCTSIZE * 0], quantptr[DCTSIZE * 0]);
+ tmp1 = DEQUANTIZE(inptr[DCTSIZE * 2], quantptr[DCTSIZE * 2]);
+ tmp2 = DEQUANTIZE(inptr[DCTSIZE * 4], quantptr[DCTSIZE * 4]);
+ tmp3 = DEQUANTIZE(inptr[DCTSIZE * 6], quantptr[DCTSIZE * 6]);
tmp10 = tmp0 + tmp2; /* phase 3 */
tmp11 = tmp0 - tmp2;
/* Odd part */
- tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
- tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
- tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
- tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
+ tmp4 = DEQUANTIZE(inptr[DCTSIZE * 1], quantptr[DCTSIZE * 1]);
+ tmp5 = DEQUANTIZE(inptr[DCTSIZE * 3], quantptr[DCTSIZE * 3]);
+ tmp6 = DEQUANTIZE(inptr[DCTSIZE * 5], quantptr[DCTSIZE * 5]);
+ tmp7 = DEQUANTIZE(inptr[DCTSIZE * 7], quantptr[DCTSIZE * 7]);
z13 = tmp6 + tmp5; /* phase 6 */
z10 = tmp6 - tmp5;
z5 = MULTIPLY(z10 + z12, FIX_1_847759065); /* 2*c2 */
tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */
- tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; /* -2*(c2+c6) */
+ tmp12 = MULTIPLY(z10, -FIX_2_613125930) + z5; /* -2*(c2+c6) */
tmp6 = tmp12 - tmp7; /* phase 2 */
tmp5 = tmp11 - tmp6;
tmp4 = tmp10 + tmp5;
- wsptr[DCTSIZE*0] = (int) (tmp0 + tmp7);
- wsptr[DCTSIZE*7] = (int) (tmp0 - tmp7);
- wsptr[DCTSIZE*1] = (int) (tmp1 + tmp6);
- wsptr[DCTSIZE*6] = (int) (tmp1 - tmp6);
- wsptr[DCTSIZE*2] = (int) (tmp2 + tmp5);
- wsptr[DCTSIZE*5] = (int) (tmp2 - tmp5);
- wsptr[DCTSIZE*4] = (int) (tmp3 + tmp4);
- wsptr[DCTSIZE*3] = (int) (tmp3 - tmp4);
+ wsptr[DCTSIZE * 0] = (int)(tmp0 + tmp7);
+ wsptr[DCTSIZE * 7] = (int)(tmp0 - tmp7);
+ wsptr[DCTSIZE * 1] = (int)(tmp1 + tmp6);
+ wsptr[DCTSIZE * 6] = (int)(tmp1 - tmp6);
+ wsptr[DCTSIZE * 2] = (int)(tmp2 + tmp5);
+ wsptr[DCTSIZE * 5] = (int)(tmp2 - tmp5);
+ wsptr[DCTSIZE * 4] = (int)(tmp3 + tmp4);
+ wsptr[DCTSIZE * 3] = (int)(tmp3 - tmp4);
inptr++; /* advance pointers to next column */
quantptr++;
if (wsptr[1] == 0 && wsptr[2] == 0 && wsptr[3] == 0 && wsptr[4] == 0 &&
wsptr[5] == 0 && wsptr[6] == 0 && wsptr[7] == 0) {
/* AC terms all zero */
- JSAMPLE dcval = range_limit[IDESCALE(wsptr[0], PASS1_BITS+3)
- & RANGE_MASK];
+ _JSAMPLE dcval =
+ range_limit[IDESCALE(wsptr[0], PASS1_BITS + 3) & RANGE_MASK];
outptr[0] = dcval;
outptr[1] = dcval;
/* Even part */
- tmp10 = ((DCTELEM) wsptr[0] + (DCTELEM) wsptr[4]);
- tmp11 = ((DCTELEM) wsptr[0] - (DCTELEM) wsptr[4]);
+ tmp10 = ((DCTELEM)wsptr[0] + (DCTELEM)wsptr[4]);
+ tmp11 = ((DCTELEM)wsptr[0] - (DCTELEM)wsptr[4]);
- tmp13 = ((DCTELEM) wsptr[2] + (DCTELEM) wsptr[6]);
- tmp12 = MULTIPLY((DCTELEM) wsptr[2] - (DCTELEM) wsptr[6], FIX_1_414213562)
- - tmp13;
+ tmp13 = ((DCTELEM)wsptr[2] + (DCTELEM)wsptr[6]);
+ tmp12 =
+ MULTIPLY((DCTELEM)wsptr[2] - (DCTELEM)wsptr[6], FIX_1_414213562) - tmp13;
tmp0 = tmp10 + tmp13;
tmp3 = tmp10 - tmp13;
/* Odd part */
- z13 = (DCTELEM) wsptr[5] + (DCTELEM) wsptr[3];
- z10 = (DCTELEM) wsptr[5] - (DCTELEM) wsptr[3];
- z11 = (DCTELEM) wsptr[1] + (DCTELEM) wsptr[7];
- z12 = (DCTELEM) wsptr[1] - (DCTELEM) wsptr[7];
+ z13 = (DCTELEM)wsptr[5] + (DCTELEM)wsptr[3];
+ z10 = (DCTELEM)wsptr[5] - (DCTELEM)wsptr[3];
+ z11 = (DCTELEM)wsptr[1] + (DCTELEM)wsptr[7];
+ z12 = (DCTELEM)wsptr[1] - (DCTELEM)wsptr[7];
tmp7 = z11 + z13; /* phase 5 */
tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); /* 2*c4 */
z5 = MULTIPLY(z10 + z12, FIX_1_847759065); /* 2*c2 */
tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */
- tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; /* -2*(c2+c6) */
+ tmp12 = MULTIPLY(z10, -FIX_2_613125930) + z5; /* -2*(c2+c6) */
tmp6 = tmp12 - tmp7; /* phase 2 */
tmp5 = tmp11 - tmp6;
/* Final output stage: scale down by a factor of 8 and range-limit */
- outptr[0] = range_limit[IDESCALE(tmp0 + tmp7, PASS1_BITS+3)
- & RANGE_MASK];
- outptr[7] = range_limit[IDESCALE(tmp0 - tmp7, PASS1_BITS+3)
- & RANGE_MASK];
- outptr[1] = range_limit[IDESCALE(tmp1 + tmp6, PASS1_BITS+3)
- & RANGE_MASK];
- outptr[6] = range_limit[IDESCALE(tmp1 - tmp6, PASS1_BITS+3)
- & RANGE_MASK];
- outptr[2] = range_limit[IDESCALE(tmp2 + tmp5, PASS1_BITS+3)
- & RANGE_MASK];
- outptr[5] = range_limit[IDESCALE(tmp2 - tmp5, PASS1_BITS+3)
- & RANGE_MASK];
- outptr[4] = range_limit[IDESCALE(tmp3 + tmp4, PASS1_BITS+3)
- & RANGE_MASK];
- outptr[3] = range_limit[IDESCALE(tmp3 - tmp4, PASS1_BITS+3)
- & RANGE_MASK];
+ outptr[0] =
+ range_limit[IDESCALE(tmp0 + tmp7, PASS1_BITS + 3) & RANGE_MASK];
+ outptr[7] =
+ range_limit[IDESCALE(tmp0 - tmp7, PASS1_BITS + 3) & RANGE_MASK];
+ outptr[1] =
+ range_limit[IDESCALE(tmp1 + tmp6, PASS1_BITS + 3) & RANGE_MASK];
+ outptr[6] =
+ range_limit[IDESCALE(tmp1 - tmp6, PASS1_BITS + 3) & RANGE_MASK];
+ outptr[2] =
+ range_limit[IDESCALE(tmp2 + tmp5, PASS1_BITS + 3) & RANGE_MASK];
+ outptr[5] =
+ range_limit[IDESCALE(tmp2 - tmp5, PASS1_BITS + 3) & RANGE_MASK];
+ outptr[4] =
+ range_limit[IDESCALE(tmp3 + tmp4, PASS1_BITS + 3) & RANGE_MASK];
+ outptr[3] =
+ range_limit[IDESCALE(tmp3 - tmp4, PASS1_BITS + 3) & RANGE_MASK];
wsptr += DCTSIZE; /* advance pointer to next row */
}
projects / platform / upstream / libjpeg-turbo.git / blobdiff