-/*\r
-\r
- * jidctflt.c\r
-\r
- *\r
-\r
- * Copyright (C) 1994, Thomas G. Lane.\r
-\r
- * This file is part of the Independent JPEG Group's software.\r
-\r
- * For conditions of distribution and use, see the accompanying README file.\r
-\r
- *\r
-\r
- * This file contains a floating-point implementation of the\r
-\r
- * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine\r
-\r
- * must also perform dequantization of the input coefficients.\r
-\r
- *\r
-\r
- * This implementation should be more accurate than either of the integer\r
-\r
- * IDCT implementations. However, it may not give the same results on all\r
-\r
- * machines because of differences in roundoff behavior. Speed will depend\r
-\r
- * on the hardware's floating point capacity.\r
-\r
- *\r
-\r
- * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT\r
-\r
- * on each row (or vice versa, but it's more convenient to emit a row at\r
-\r
- * a time). Direct algorithms are also available, but they are much more\r
-\r
- * complex and seem not to be any faster when reduced to code.\r
-\r
- *\r
-\r
- * This implementation is based on Arai, Agui, and Nakajima's algorithm for\r
-\r
- * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in\r
-\r
- * Japanese, but the algorithm is described in the Pennebaker & Mitchell\r
-\r
- * JPEG textbook (see REFERENCES section in file README). The following code\r
-\r
- * is based directly on figure 4-8 in P&M.\r
-\r
- * While an 8-point DCT cannot be done in less than 11 multiplies, it is\r
-\r
- * possible to arrange the computation so that many of the multiplies are\r
-\r
- * simple scalings of the final outputs. These multiplies can then be\r
-\r
- * folded into the multiplications or divisions by the JPEG quantization\r
-\r
- * table entries. The AA&N method leaves only 5 multiplies and 29 adds\r
-\r
- * to be done in the DCT itself.\r
-\r
- * The primary disadvantage of this method is that with a fixed-point\r
-\r
- * implementation, accuracy is lost due to imprecise representation of the\r
-\r
- * scaled quantization values. However, that problem does not arise if\r
-\r
- * we use floating point arithmetic.\r
-\r
- */\r
-\r
-\r
-\r
-#define JPEG_INTERNALS\r
-\r
-#include "jinclude.h"\r
-\r
-#include "radiant_jpeglib.h"\r
-\r
-#include "jdct.h" /* Private declarations for DCT subsystem */\r
-\r
-\r
-\r
-#ifdef DCT_FLOAT_SUPPORTED\r
-\r
-\r
-\r
-\r
-\r
-/*\r
-\r
- * This module is specialized to the case DCTSIZE = 8.\r
-\r
- */\r
-\r
-\r
-\r
-#if DCTSIZE != 8\r
-\r
- Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */\r
-\r
-#endif\r
-\r
-\r
-\r
-\r
-\r
-/* Dequantize a coefficient by multiplying it by the multiplier-table\r
-\r
- * entry; produce a float result.\r
-\r
- */\r
-\r
-\r
-\r
-#define DEQUANTIZE(coef,quantval) (((FAST_FLOAT) (coef)) * (quantval))\r
-\r
-\r
-\r
-\r
-\r
-/*\r
-\r
- * Perform dequantization and inverse DCT on one block of coefficients.\r
-\r
- */\r
-\r
-\r
-\r
-GLOBAL void\r
-\r
-jpeg_idct_float (j_decompress_ptr cinfo, jpeg_component_info * compptr,\r
-\r
- JCOEFPTR coef_block,\r
-\r
- JSAMPARRAY output_buf, JDIMENSION output_col)\r
-\r
-{\r
-\r
- FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;\r
-\r
- FAST_FLOAT tmp10, tmp11, tmp12, tmp13;\r
-\r
- FAST_FLOAT z5, z10, z11, z12, z13;\r
-\r
- JCOEFPTR inptr;\r
-\r
- FLOAT_MULT_TYPE * quantptr;\r
-\r
- FAST_FLOAT * wsptr;\r
-\r
- JSAMPROW outptr;\r
-\r
- JSAMPLE *range_limit = IDCT_range_limit(cinfo);\r
-\r
- int ctr;\r
-\r
- FAST_FLOAT workspace[DCTSIZE2]; /* buffers data between passes */\r
-\r
- SHIFT_TEMPS\r
-\r
-\r
-\r
- /* Pass 1: process columns from input, store into work array. */\r
-\r
-\r
-\r
- inptr = coef_block;\r
-\r
- quantptr = (FLOAT_MULT_TYPE *) compptr->dct_table;\r
-\r
- wsptr = workspace;\r
-\r
- for (ctr = DCTSIZE; ctr > 0; ctr--) {\r
-\r
- /* Due to quantization, we will usually find that many of the input\r
-\r
- * coefficients are zero, especially the AC terms. We can exploit this\r
-\r
- * by short-circuiting the IDCT calculation for any column in which all\r
-\r
- * the AC terms are zero. In that case each output is equal to the\r
-\r
- * DC coefficient (with scale factor as needed).\r
-\r
- * With typical images and quantization tables, half or more of the\r
-\r
- * column DCT calculations can be simplified this way.\r
-\r
- */\r
-\r
- \r
-\r
- if ((inptr[DCTSIZE*1] | inptr[DCTSIZE*2] | inptr[DCTSIZE*3] |\r
-\r
- inptr[DCTSIZE*4] | inptr[DCTSIZE*5] | inptr[DCTSIZE*6] |\r
-\r
- inptr[DCTSIZE*7]) == 0) {\r
-\r
- /* AC terms all zero */\r
-\r
- FAST_FLOAT dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);\r
-\r
- \r
-\r
- wsptr[DCTSIZE*0] = dcval;\r
-\r
- wsptr[DCTSIZE*1] = dcval;\r
-\r
- wsptr[DCTSIZE*2] = dcval;\r
-\r
- wsptr[DCTSIZE*3] = dcval;\r
-\r
- wsptr[DCTSIZE*4] = dcval;\r
-\r
- wsptr[DCTSIZE*5] = dcval;\r
-\r
- wsptr[DCTSIZE*6] = dcval;\r
-\r
- wsptr[DCTSIZE*7] = dcval;\r
-\r
- \r
-\r
- inptr++; /* advance pointers to next column */\r
-\r
- quantptr++;\r
-\r
- wsptr++;\r
-\r
- continue;\r
-\r
- }\r
-\r
- \r
-\r
- /* Even part */\r
-\r
-\r
-\r
- tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);\r
-\r
- tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);\r
-\r
- tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);\r
-\r
- tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);\r
-\r
-\r
-\r
- tmp10 = tmp0 + tmp2; /* phase 3 */\r
-\r
- tmp11 = tmp0 - tmp2;\r
-\r
-\r
-\r
- tmp13 = tmp1 + tmp3; /* phases 5-3 */\r
-\r
- tmp12 = (tmp1 - tmp3) * ((FAST_FLOAT) 1.414213562) - tmp13; /* 2*c4 */\r
-\r
-\r
-\r
- tmp0 = tmp10 + tmp13; /* phase 2 */\r
-\r
- tmp3 = tmp10 - tmp13;\r
-\r
- tmp1 = tmp11 + tmp12;\r
-\r
- tmp2 = tmp11 - tmp12;\r
-\r
- \r
-\r
- /* Odd part */\r
-\r
-\r
-\r
- tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);\r
-\r
- tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);\r
-\r
- tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);\r
-\r
- tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);\r
-\r
-\r
-\r
- z13 = tmp6 + tmp5; /* phase 6 */\r
-\r
- z10 = tmp6 - tmp5;\r
-\r
- z11 = tmp4 + tmp7;\r
-\r
- z12 = tmp4 - tmp7;\r
-\r
-\r
-\r
- tmp7 = z11 + z13; /* phase 5 */\r
-\r
- tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562); /* 2*c4 */\r
-\r
-\r
-\r
- z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */\r
-\r
- tmp10 = ((FAST_FLOAT) 1.082392200) * z12 - z5; /* 2*(c2-c6) */\r
-\r
- tmp12 = ((FAST_FLOAT) -2.613125930) * z10 + z5; /* -2*(c2+c6) */\r
-\r
-\r
-\r
- tmp6 = tmp12 - tmp7; /* phase 2 */\r
-\r
- tmp5 = tmp11 - tmp6;\r
-\r
- tmp4 = tmp10 + tmp5;\r
-\r
-\r
-\r
- wsptr[DCTSIZE*0] = tmp0 + tmp7;\r
-\r
- wsptr[DCTSIZE*7] = tmp0 - tmp7;\r
-\r
- wsptr[DCTSIZE*1] = tmp1 + tmp6;\r
-\r
- wsptr[DCTSIZE*6] = tmp1 - tmp6;\r
-\r
- wsptr[DCTSIZE*2] = tmp2 + tmp5;\r
-\r
- wsptr[DCTSIZE*5] = tmp2 - tmp5;\r
-\r
- wsptr[DCTSIZE*4] = tmp3 + tmp4;\r
-\r
- wsptr[DCTSIZE*3] = tmp3 - tmp4;\r
-\r
-\r
-\r
- inptr++; /* advance pointers to next column */\r
-\r
- quantptr++;\r
-\r
- wsptr++;\r
-\r
- }\r
-\r
- \r
-\r
- /* Pass 2: process rows from work array, store into output array. */\r
-\r
- /* Note that we must descale the results by a factor of 8 == 2**3. */\r
-\r
-\r
-\r
- wsptr = workspace;\r
-\r
- for (ctr = 0; ctr < DCTSIZE; ctr++) {\r
-\r
- outptr = output_buf[ctr] + output_col;\r
-\r
- /* Rows of zeroes can be exploited in the same way as we did with columns.\r
-\r
- * However, the column calculation has created many nonzero AC terms, so\r
-\r
- * the simplification applies less often (typically 5% to 10% of the time).\r
-\r
- * And testing floats for zero is relatively expensive, so we don't bother.\r
-\r
- */\r
-\r
- \r
-\r
- /* Even part */\r
-\r
-\r
-\r
- tmp10 = wsptr[0] + wsptr[4];\r
-\r
- tmp11 = wsptr[0] - wsptr[4];\r
-\r
-\r
-\r
- tmp13 = wsptr[2] + wsptr[6];\r
-\r
- tmp12 = (wsptr[2] - wsptr[6]) * ((FAST_FLOAT) 1.414213562) - tmp13;\r
-\r
-\r
-\r
- tmp0 = tmp10 + tmp13;\r
-\r
- tmp3 = tmp10 - tmp13;\r
-\r
- tmp1 = tmp11 + tmp12;\r
-\r
- tmp2 = tmp11 - tmp12;\r
-\r
-\r
-\r
- /* Odd part */\r
-\r
-\r
-\r
- z13 = wsptr[5] + wsptr[3];\r
-\r
- z10 = wsptr[5] - wsptr[3];\r
-\r
- z11 = wsptr[1] + wsptr[7];\r
-\r
- z12 = wsptr[1] - wsptr[7];\r
-\r
-\r
-\r
- tmp7 = z11 + z13;\r
-\r
- tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562);\r
-\r
-\r
-\r
- z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */\r
-\r
- tmp10 = ((FAST_FLOAT) 1.082392200) * z12 - z5; /* 2*(c2-c6) */\r
-\r
- tmp12 = ((FAST_FLOAT) -2.613125930) * z10 + z5; /* -2*(c2+c6) */\r
-\r
-\r
-\r
- tmp6 = tmp12 - tmp7;\r
-\r
- tmp5 = tmp11 - tmp6;\r
-\r
- tmp4 = tmp10 + tmp5;\r
-\r
-\r
-\r
- /* Final output stage: scale down by a factor of 8 and range-limit */\r
-\r
-\r
-\r
- outptr[0] = range_limit[(int) DESCALE((INT32) (tmp0 + tmp7), 3)\r
-\r
- & RANGE_MASK];\r
-\r
- outptr[7] = range_limit[(int) DESCALE((INT32) (tmp0 - tmp7), 3)\r
-\r
- & RANGE_MASK];\r
-\r
- outptr[1] = range_limit[(int) DESCALE((INT32) (tmp1 + tmp6), 3)\r
-\r
- & RANGE_MASK];\r
-\r
- outptr[6] = range_limit[(int) DESCALE((INT32) (tmp1 - tmp6), 3)\r
-\r
- & RANGE_MASK];\r
-\r
- outptr[2] = range_limit[(int) DESCALE((INT32) (tmp2 + tmp5), 3)\r
-\r
- & RANGE_MASK];\r
-\r
- outptr[5] = range_limit[(int) DESCALE((INT32) (tmp2 - tmp5), 3)\r
-\r
- & RANGE_MASK];\r
-\r
- outptr[4] = range_limit[(int) DESCALE((INT32) (tmp3 + tmp4), 3)\r
-\r
- & RANGE_MASK];\r
-\r
- outptr[3] = range_limit[(int) DESCALE((INT32) (tmp3 - tmp4), 3)\r
-\r
- & RANGE_MASK];\r
-\r
- \r
-\r
- wsptr += DCTSIZE; /* advance pointer to next row */\r
-\r
- }\r
-\r
-}\r
-\r
-\r
-\r
-#endif /* DCT_FLOAT_SUPPORTED */\r
-\r
+/*
+
+ * jidctflt.c
+
+ *
+
+ * Copyright (C) 1994, 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 floating-point implementation of the
+
+ * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine
+
+ * must also perform dequantization of the input coefficients.
+
+ *
+
+ * This implementation should be more accurate than either of the integer
+
+ * IDCT implementations. However, it may not give the same results on all
+
+ * machines because of differences in roundoff behavior. Speed will depend
+
+ * on the hardware's floating point capacity.
+
+ *
+
+ * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT
+
+ * on each row (or vice versa, but it's more convenient to emit a row at
+
+ * a time). 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 a fixed-point
+
+ * implementation, accuracy is lost due to imprecise representation of the
+
+ * scaled quantization values. However, that problem does not arise if
+
+ * we use floating point arithmetic.
+
+ */
+
+
+
+#define JPEG_INTERNALS
+
+#include "jinclude.h"
+
+#include "radiant_jpeglib.h"
+
+#include "jdct.h" /* Private declarations for DCT subsystem */
+
+
+
+#ifdef DCT_FLOAT_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
+
+
+
+
+
+/* Dequantize a coefficient by multiplying it by the multiplier-table
+
+ * entry; produce a float result.
+
+ */
+
+
+
+#define DEQUANTIZE(coef,quantval) (((FAST_FLOAT) (coef)) * (quantval))
+
+
+
+
+
+/*
+
+ * Perform dequantization and inverse DCT on one block of coefficients.
+
+ */
+
+
+
+GLOBAL void
+
+jpeg_idct_float (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+
+ JCOEFPTR coef_block,
+
+ JSAMPARRAY output_buf, JDIMENSION output_col)
+
+{
+
+ FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
+
+ FAST_FLOAT tmp10, tmp11, tmp12, tmp13;
+
+ FAST_FLOAT z5, z10, z11, z12, z13;
+
+ JCOEFPTR inptr;
+
+ FLOAT_MULT_TYPE * quantptr;
+
+ FAST_FLOAT * wsptr;
+
+ JSAMPROW outptr;
+
+ JSAMPLE *range_limit = IDCT_range_limit(cinfo);
+
+ int ctr;
+
+ FAST_FLOAT workspace[DCTSIZE2]; /* buffers data between passes */
+
+ SHIFT_TEMPS
+
+
+
+ /* Pass 1: process columns from input, store into work array. */
+
+
+
+ inptr = coef_block;
+
+ quantptr = (FLOAT_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
+
+ * coefficients are zero, especially the AC terms. We can exploit this
+
+ * by short-circuiting the IDCT calculation for any column in which all
+
+ * the AC terms are zero. In that case each output is equal to the
+
+ * DC coefficient (with scale factor as needed).
+
+ * With typical images and quantization tables, half or more of the
+
+ * column DCT calculations can be simplified this way.
+
+ */
+
+
+
+ if ((inptr[DCTSIZE*1] | inptr[DCTSIZE*2] | inptr[DCTSIZE*3] |
+
+ inptr[DCTSIZE*4] | inptr[DCTSIZE*5] | inptr[DCTSIZE*6] |
+
+ inptr[DCTSIZE*7]) == 0) {
+
+ /* AC terms all zero */
+
+ FAST_FLOAT dcval = 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;
+
+
+
+ inptr++; /* advance pointers to next column */
+
+ quantptr++;
+
+ wsptr++;
+
+ continue;
+
+ }
+
+
+
+ /* 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]);
+
+
+
+ tmp10 = tmp0 + tmp2; /* phase 3 */
+
+ tmp11 = tmp0 - tmp2;
+
+
+
+ tmp13 = tmp1 + tmp3; /* phases 5-3 */
+
+ tmp12 = (tmp1 - tmp3) * ((FAST_FLOAT) 1.414213562) - tmp13; /* 2*c4 */
+
+
+
+ tmp0 = tmp10 + tmp13; /* phase 2 */
+
+ tmp3 = tmp10 - tmp13;
+
+ tmp1 = tmp11 + tmp12;
+
+ tmp2 = tmp11 - tmp12;
+
+
+
+ /* 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]);
+
+
+
+ z13 = tmp6 + tmp5; /* phase 6 */
+
+ z10 = tmp6 - tmp5;
+
+ z11 = tmp4 + tmp7;
+
+ z12 = tmp4 - tmp7;
+
+
+
+ tmp7 = z11 + z13; /* phase 5 */
+
+ tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562); /* 2*c4 */
+
+
+
+ z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */
+
+ tmp10 = ((FAST_FLOAT) 1.082392200) * z12 - z5; /* 2*(c2-c6) */
+
+ tmp12 = ((FAST_FLOAT) -2.613125930) * z10 + z5; /* -2*(c2+c6) */
+
+
+
+ tmp6 = tmp12 - tmp7; /* phase 2 */
+
+ tmp5 = tmp11 - tmp6;
+
+ tmp4 = tmp10 + tmp5;
+
+
+
+ wsptr[DCTSIZE*0] = tmp0 + tmp7;
+
+ wsptr[DCTSIZE*7] = tmp0 - tmp7;
+
+ wsptr[DCTSIZE*1] = tmp1 + tmp6;
+
+ wsptr[DCTSIZE*6] = tmp1 - tmp6;
+
+ wsptr[DCTSIZE*2] = tmp2 + tmp5;
+
+ wsptr[DCTSIZE*5] = tmp2 - tmp5;
+
+ wsptr[DCTSIZE*4] = tmp3 + tmp4;
+
+ wsptr[DCTSIZE*3] = tmp3 - tmp4;
+
+
+
+ inptr++; /* advance pointers to next column */
+
+ quantptr++;
+
+ wsptr++;
+
+ }
+
+
+
+ /* Pass 2: process rows from work array, store into output array. */
+
+ /* Note that we must descale the results by a factor of 8 == 2**3. */
+
+
+
+ wsptr = workspace;
+
+ for (ctr = 0; ctr < DCTSIZE; ctr++) {
+
+ outptr = output_buf[ctr] + output_col;
+
+ /* Rows of zeroes can be exploited in the same way as we did with columns.
+
+ * However, the column calculation has created many nonzero AC terms, so
+
+ * the simplification applies less often (typically 5% to 10% of the time).
+
+ * And testing floats for zero is relatively expensive, so we don't bother.
+
+ */
+
+
+
+ /* Even part */
+
+
+
+ tmp10 = wsptr[0] + wsptr[4];
+
+ tmp11 = wsptr[0] - wsptr[4];
+
+
+
+ tmp13 = wsptr[2] + wsptr[6];
+
+ tmp12 = (wsptr[2] - wsptr[6]) * ((FAST_FLOAT) 1.414213562) - tmp13;
+
+
+
+ tmp0 = tmp10 + tmp13;
+
+ tmp3 = tmp10 - tmp13;
+
+ tmp1 = tmp11 + tmp12;
+
+ tmp2 = tmp11 - tmp12;
+
+
+
+ /* Odd part */
+
+
+
+ z13 = wsptr[5] + wsptr[3];
+
+ z10 = wsptr[5] - wsptr[3];
+
+ z11 = wsptr[1] + wsptr[7];
+
+ z12 = wsptr[1] - wsptr[7];
+
+
+
+ tmp7 = z11 + z13;
+
+ tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562);
+
+
+
+ z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */
+
+ tmp10 = ((FAST_FLOAT) 1.082392200) * z12 - z5; /* 2*(c2-c6) */
+
+ tmp12 = ((FAST_FLOAT) -2.613125930) * z10 + z5; /* -2*(c2+c6) */
+
+
+
+ tmp6 = tmp12 - tmp7;
+
+ tmp5 = tmp11 - tmp6;
+
+ tmp4 = tmp10 + tmp5;
+
+
+
+ /* Final output stage: scale down by a factor of 8 and range-limit */
+
+
+
+ outptr[0] = range_limit[(int) DESCALE((INT32) (tmp0 + tmp7), 3)
+
+ & RANGE_MASK];
+
+ outptr[7] = range_limit[(int) DESCALE((INT32) (tmp0 - tmp7), 3)
+
+ & RANGE_MASK];
+
+ outptr[1] = range_limit[(int) DESCALE((INT32) (tmp1 + tmp6), 3)
+
+ & RANGE_MASK];
+
+ outptr[6] = range_limit[(int) DESCALE((INT32) (tmp1 - tmp6), 3)
+
+ & RANGE_MASK];
+
+ outptr[2] = range_limit[(int) DESCALE((INT32) (tmp2 + tmp5), 3)
+
+ & RANGE_MASK];
+
+ outptr[5] = range_limit[(int) DESCALE((INT32) (tmp2 - tmp5), 3)
+
+ & RANGE_MASK];
+
+ outptr[4] = range_limit[(int) DESCALE((INT32) (tmp3 + tmp4), 3)
+
+ & RANGE_MASK];
+
+ outptr[3] = range_limit[(int) DESCALE((INT32) (tmp3 - tmp4), 3)
+
+ & RANGE_MASK];
+
+
+
+ wsptr += DCTSIZE; /* advance pointer to next row */
+
+ }
+
+}
+
+
+
+#endif /* DCT_FLOAT_SUPPORTED */
+
projects / xonotic / netradiant.git / blobdiff