diff options
Diffstat (limited to 'libavcodec/cbrt_tablegen.h')
| -rw-r--r-- | libavcodec/cbrt_tablegen.h | 61 |
1 files changed, 41 insertions, 20 deletions
diff --git a/libavcodec/cbrt_tablegen.h b/libavcodec/cbrt_tablegen.h index 60d900a..9af18d8 100644 --- a/libavcodec/cbrt_tablegen.h +++ b/libavcodec/cbrt_tablegen.h @@ -3,20 +3,20 @@ * * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de> * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * - * Libav is distributed in the hope that it will be useful, + * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public - * License along with Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -25,28 +25,49 @@ #include <stdint.h> #include <math.h> +#include "libavutil/attributes.h" +#include "libavutil/intfloat.h" +#include "libavcodec/aac_defines.h" -#if CONFIG_HARDCODED_TABLES -#define cbrt_tableinit() -#include "libavcodec/cbrt_tables.h" +#if USE_FIXED +#define CBRT(x) lrint((x) * 8192) #else -static uint32_t cbrt_tab[1 << 13]; +#define CBRT(x) av_float2int((float)(x)) +#endif -static void cbrt_tableinit(void) +uint32_t AAC_RENAME(ff_cbrt_tab)[1 << 13]; + +av_cold void AAC_RENAME(ff_cbrt_tableinit)(void) { - if (!cbrt_tab[(1<<13) - 1]) { - int i; - /* cbrtf() isn't available on all systems, so we use powf(). */ - for (i = 0; i < 1<<13; i++) { - union { - float f; - uint32_t i; - } f; - f.f = powf(i, 1.0 / 3.0) * i; - cbrt_tab[i] = f.i; + static double cbrt_tab_dbl[1 << 13]; + if (!AAC_RENAME(ff_cbrt_tab)[(1<<13) - 1]) { + int i, j, k; + double cbrt_val; + + for (i = 1; i < 1<<13; i++) + cbrt_tab_dbl[i] = 1; + + /* have to take care of non-squarefree numbers */ + for (i = 2; i < 90; i++) { + if (cbrt_tab_dbl[i] == 1) { + cbrt_val = i * cbrt(i); + for (k = i; k < 1<<13; k *= i) + for (j = k; j < 1<<13; j += k) + cbrt_tab_dbl[j] *= cbrt_val; + } } + + for (i = 91; i <= 8191; i+= 2) { + if (cbrt_tab_dbl[i] == 1) { + cbrt_val = i * cbrt(i); + for (j = i; j < 1<<13; j += i) + cbrt_tab_dbl[j] *= cbrt_val; + } + } + + for (i = 0; i < 1<<13; i++) + AAC_RENAME(ff_cbrt_tab)[i] = CBRT(cbrt_tab_dbl[i]); } } -#endif /* CONFIG_HARDCODED_TABLES */ #endif /* AVCODEC_CBRT_TABLEGEN_H */ |
