diff options
Diffstat (limited to 'converter/ppm/ppmtompeg/mfwddct.c')
| -rw-r--r-- | converter/ppm/ppmtompeg/mfwddct.c | 180 |
1 files changed, 94 insertions, 86 deletions
diff --git a/converter/ppm/ppmtompeg/mfwddct.c b/converter/ppm/ppmtompeg/mfwddct.c index 4643bf25..75c3a718 100644 --- a/converter/ppm/ppmtompeg/mfwddct.c +++ b/converter/ppm/ppmtompeg/mfwddct.c @@ -122,33 +122,68 @@ #define OSIN_5_16 OCOS_3_16 #define OCOS_5_16 OSIN_3_16 -/* Prototypes */ -void reference_fwd_dct _ANSI_ARGS_((Block block, Block dest)); -void mp_fwd_dct_fast _ANSI_ARGS_((Block data2d, Block dest2d)); -void init_fdct _ANSI_ARGS_((void)); -/* - * -------------------------------------------------------------- - * - * mp_fwd_dct_block2 -- - * - * Select the appropriate mp_fwd_dct routine - * - * Results: None - * - * Side effects: None - * - * -------------------------------------------------------------- - */ -extern boolean pureDCT; -void -mp_fwd_dct_block2(data, dest) - Block data, dest; +static double trans_coef[8][8]; /* transform coefficients */ + + + +static void reference_fwd_dct(block, dest) +Block block, dest; { - if (pureDCT) reference_fwd_dct(data, dest); - else mp_fwd_dct_fast(data, dest); + int i, j, k; + double s; + double tmp[64]; + + if (DoLaplace) { + LaplaceNum++; + } + + for (i=0; i<8; i++) + for (j=0; j<8; j++) + { + s = 0.0; + + for (k=0; k<8; k++) + s += trans_coef[j][k] * block[i][k]; + + tmp[8*i+j] = s; + } + + for (i=0; i<8; i++) + for (j=0; j<8; j++) + { + s = 0.0; + + for (k=0; k<8; k++) + s += trans_coef[i][k] * tmp[8*k+j]; + + if (collect_quant) { + fprintf(collect_quant_fp, "%d %f\n", 8*i+j, s); + } + if (DoLaplace) { + L1[LaplaceCnum][i*8+j] += s*s; + L2[LaplaceCnum][i*8+j] += s; + } + + + dest[i][j] = (int)floor(s+0.499999); + /* + * reason for adding 0.499999 instead of 0.5: + * s is quite often x.5 (at least for i and/or j = 0 or 4) + * and setting the rounding threshold exactly to 0.5 leads to an + * extremely high arithmetic implementation dependency of the result; + * s being between x.5 and x.500001 (which is now incorrectly rounded + * downwards instead of upwards) is assumed to occur less often + * (if at all) + */ + } } + + +static void +mp_fwd_dct_fast(data2d, dest2d) + Block data2d, dest2d; /* * -------------------------------------------------------------- * @@ -166,9 +201,6 @@ mp_fwd_dct_block2(data, dest) * -------------------------------------------------------------- */ -void -mp_fwd_dct_fast(data2d, dest2d) - Block data2d, dest2d; { int16 *data = (int16 *) data2d; /* this algorithm wants * a 1-d array */ @@ -236,10 +268,12 @@ mp_fwd_dct_fast(data2d, dest2d) tmp13 = tmp0 - tmp3; outptr[0] = (int16) UNFIXH((tmp10 + tmp11) * SIN_1_4); - outptr[DCTSIZE * 4] = (int16) UNFIXH((tmp10 - tmp11) * COS_1_4); - - outptr[DCTSIZE * 2] = (int16) UNFIXH(tmp13 * COS_1_8 + tmp12 * SIN_1_8); - outptr[DCTSIZE * 6] = (int16) UNFIXH(tmp13 * SIN_1_8 - tmp12 * COS_1_8); + outptr[DCTSIZE * 4] = + (int16) UNFIXH((tmp10 - tmp11) * COS_1_4); + outptr[DCTSIZE * 2] = + (int16) UNFIXH(tmp13 * COS_1_8 + tmp12 * SIN_1_8); + outptr[DCTSIZE * 6] = + (int16) UNFIXH(tmp13 * SIN_1_8 - tmp12 * COS_1_8); tmp16 = UNFIXO((tmp6 + tmp5) * SIN_1_4); tmp15 = UNFIXO((tmp6 - tmp5) * COS_1_4); @@ -257,10 +291,14 @@ mp_fwd_dct_fast(data2d, dest2d) tmp26 = tmp7 - tmp16; tmp17 = tmp7 + tmp16; - outptr[DCTSIZE] = (int16) UNFIXH(tmp17 * OCOS_1_16 + tmp14 * OSIN_1_16); - outptr[DCTSIZE * 7] = (int16) UNFIXH(tmp17 * OCOS_7_16 - tmp14 * OSIN_7_16); - outptr[DCTSIZE * 5] = (int16) UNFIXH(tmp26 * OCOS_5_16 + tmp25 * OSIN_5_16); - outptr[DCTSIZE * 3] = (int16) UNFIXH(tmp26 * OCOS_3_16 - tmp25 * OSIN_3_16); + outptr[DCTSIZE] = + (int16) UNFIXH(tmp17 * OCOS_1_16 + tmp14 * OSIN_1_16); + outptr[DCTSIZE * 7] = + (int16) UNFIXH(tmp17 * OCOS_7_16 - tmp14 * OSIN_7_16); + outptr[DCTSIZE * 5] = + (int16) UNFIXH(tmp26 * OCOS_5_16 + tmp25 * OSIN_5_16); + outptr[DCTSIZE * 3] = + (int16) UNFIXH(tmp26 * OCOS_3_16 - tmp25 * OSIN_3_16); inptr += DCTSIZE; /* advance inptr to next row */ outptr++; /* advance outptr to next column */ @@ -285,6 +323,28 @@ mp_fwd_dct_fast(data2d, dest2d) } +extern boolean pureDCT; +void +mp_fwd_dct_block2(data, dest) + DCTBLOCK_2D data, dest; +/* + * -------------------------------------------------------------- + * + * mp_fwd_dct_block2 -- + * + * Select the appropriate mp_fwd_dct routine + * + * Results: None + * + * Side effects: None + * + * -------------------------------------------------------------- + */ +{ + if (pureDCT) reference_fwd_dct(data, dest); + else mp_fwd_dct_fast(data, dest); +} + /* Modifies from the MPEG2 verification coder */ /* fdctref.c, forward discrete cosine transform, double precision */ @@ -323,9 +383,6 @@ mp_fwd_dct_fast(data2d, dest2d) #endif #endif -/* private data */ -static double trans_coef[8][8]; /* transform coefficients */ - void init_fdct() { int i, j; @@ -340,54 +397,5 @@ void init_fdct() } } -void reference_fwd_dct(block, dest) -Block block, dest; -{ - int i, j, k; - double s; - double tmp[64]; - - if (DoLaplace) { - LaplaceNum++; - } - - for (i=0; i<8; i++) - for (j=0; j<8; j++) - { - s = 0.0; - - for (k=0; k<8; k++) - s += trans_coef[j][k] * block[i][k]; - tmp[8*i+j] = s; - } - for (i=0; i<8; i++) - for (j=0; j<8; j++) - { - s = 0.0; - - for (k=0; k<8; k++) - s += trans_coef[i][k] * tmp[8*k+j]; - - if (collect_quant) { - fprintf(collect_quant_fp, "%d %f\n", 8*i+j, s); - } - if (DoLaplace) { - L1[LaplaceCnum][i*8+j] += s*s; - L2[LaplaceCnum][i*8+j] += s; - } - - - dest[i][j] = (int)floor(s+0.499999); - /* - * reason for adding 0.499999 instead of 0.5: - * s is quite often x.5 (at least for i and/or j = 0 or 4) - * and setting the rounding threshold exactly to 0.5 leads to an - * extremely high arithmetic implementation dependency of the result; - * s being between x.5 and x.500001 (which is now incorrectly rounded - * downwards instead of upwards) is assumed to occur less often - * (if at all) - */ - } -} |