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- #define JPEG_INTERNALS
- #include "jinclude.h"
- #include "jpeglib.h"
- #include "jdct.h"
- #ifdef DCT_FLOAT_SUPPORTED
- #if DCTSIZE != 8
- Sorry, this code only copes with 8x8 DCTs.
- #endif
- GLOBAL void
- jpeg_fdct_float (FAST_FLOAT * data)
- {
- FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
- FAST_FLOAT tmp10, tmp11, tmp12, tmp13;
- FAST_FLOAT z1, z2, z3, z4, z5, z11, z13;
- FAST_FLOAT *dataptr;
- int ctr;
-
- 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];
-
-
-
- tmp10 = tmp0 + tmp3;
- tmp13 = tmp0 - tmp3;
- tmp11 = tmp1 + tmp2;
- tmp12 = tmp1 - tmp2;
-
- dataptr[0] = tmp10 + tmp11;
- dataptr[4] = tmp10 - tmp11;
-
- z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781);
- dataptr[2] = tmp13 + z1;
- dataptr[6] = tmp13 - z1;
-
-
- tmp10 = tmp4 + tmp5;
- tmp11 = tmp5 + tmp6;
- tmp12 = tmp6 + tmp7;
-
- z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433);
- z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5;
- z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5;
- z3 = tmp11 * ((FAST_FLOAT) 0.707106781);
- z11 = tmp7 + z3;
- z13 = tmp7 - z3;
- dataptr[5] = z13 + z2;
- dataptr[3] = z13 - z2;
- dataptr[1] = z11 + z4;
- dataptr[7] = z11 - z4;
- dataptr += DCTSIZE;
- }
-
- 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];
-
-
-
- tmp10 = tmp0 + tmp3;
- tmp13 = tmp0 - tmp3;
- tmp11 = tmp1 + tmp2;
- tmp12 = tmp1 - tmp2;
-
- dataptr[DCTSIZE*0] = tmp10 + tmp11;
- dataptr[DCTSIZE*4] = tmp10 - tmp11;
-
- z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781);
- dataptr[DCTSIZE*2] = tmp13 + z1;
- dataptr[DCTSIZE*6] = tmp13 - z1;
-
-
- tmp10 = tmp4 + tmp5;
- tmp11 = tmp5 + tmp6;
- tmp12 = tmp6 + tmp7;
-
- z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433);
- z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5;
- z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5;
- z3 = tmp11 * ((FAST_FLOAT) 0.707106781);
- z11 = tmp7 + z3;
- z13 = tmp7 - z3;
- dataptr[DCTSIZE*5] = z13 + z2;
- dataptr[DCTSIZE*3] = z13 - z2;
- dataptr[DCTSIZE*1] = z11 + z4;
- dataptr[DCTSIZE*7] = z11 - z4;
- dataptr++;
- }
- }
- #endif
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