From: Justin Ruggles Date: Sun, 3 Aug 2008 21:42:43 +0000 (+0000) Subject: Hardcode the table for ungrouping 3 values in 5 bits. It will be reused by X-Git-Tag: v0.5~3370 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=602116df9b5a5f905b45baa99d4990443ee934c9;p=platform%2Fupstream%2Flibav.git Hardcode the table for ungrouping 3 values in 5 bits. It will be reused by the E-AC-3 decoder. Originally committed as revision 14527 to svn://svn.ffmpeg.org/ffmpeg/trunk --- diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c index a0123fc..1f7ca8f 100644 --- a/libavcodec/ac3dec.c +++ b/libavcodec/ac3dec.c @@ -150,9 +150,9 @@ static av_cold void ac3_tables_init(void) reference: Section 7.3.5 Ungrouping of Mantissas */ for(i=0; i<32; i++) { /* bap=1 mantissas */ - b1_mantissas[i][0] = symmetric_dequant( i / 9 , 3); - b1_mantissas[i][1] = symmetric_dequant((i % 9) / 3, 3); - b1_mantissas[i][2] = symmetric_dequant((i % 9) % 3, 3); + b1_mantissas[i][0] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][0], 3); + b1_mantissas[i][1] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][1], 3); + b1_mantissas[i][2] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][2], 3); } for(i=0; i<128; i++) { /* bap=2 mantissas */ diff --git a/libavcodec/ac3dec_data.c b/libavcodec/ac3dec_data.c index 86e61aa..a04bbc0 100644 --- a/libavcodec/ac3dec_data.c +++ b/libavcodec/ac3dec_data.c @@ -27,6 +27,22 @@ #include "ac3dec_data.h" #include "ac3.h" +/** + * table used to ungroup 3 values stored in 5 bits. + * used by bap=1 mantissas and GAQ. + * ff_ac3_ungroup_3_in_5_bits_tab[i] = { i/9, (i%9)/3, (i%9)%3 } + */ +const uint8_t ff_ac3_ungroup_3_in_5_bits_tab[32][3] = { + { 0, 0, 0 }, { 0, 0, 1 }, { 0, 0, 2 }, { 0, 1, 0 }, + { 0, 1, 1 }, { 0, 1, 2 }, { 0, 2, 0 }, { 0, 2, 1 }, + { 0, 2, 2 }, { 1, 0, 0 }, { 1, 0, 1 }, { 1, 0, 2 }, + { 1, 1, 0 }, { 1, 1, 1 }, { 1, 1, 2 }, { 1, 2, 0 }, + { 1, 2, 1 }, { 1, 2, 2 }, { 2, 0, 0 }, { 2, 0, 1 }, + { 2, 0, 2 }, { 2, 1, 0 }, { 2, 1, 1 }, { 2, 1, 2 }, + { 2, 2, 0 }, { 2, 2, 1 }, { 2, 2, 2 }, { 3, 0, 0 }, + { 3, 0, 1 }, { 3, 0, 2 }, { 3, 1, 0 }, { 3, 1, 1 } +}; + const uint8_t ff_eac3_hebap_tab[64] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 9, 9, 9, 10, 10, 10, 10, 11, diff --git a/libavcodec/ac3dec_data.h b/libavcodec/ac3dec_data.h index cbab08f..19c5f46 100644 --- a/libavcodec/ac3dec_data.h +++ b/libavcodec/ac3dec_data.h @@ -24,6 +24,7 @@ #include "libavutil/common.h" +extern const uint8_t ff_ac3_ungroup_3_in_5_bits_tab[32][3]; extern const uint8_t ff_eac3_hebap_tab[64]; extern const uint8_t ff_eac3_bits_vs_hebap[20]; extern const int16_t ff_eac3_gaq_remap_1[12];