[FFmpeg-cvslog] r14527 - in trunk/libavcodec: ac3dec.c ac3dec_data.c ac3dec_data.h
jbr
subversion
Sun Aug 3 23:42:43 CEST 2008
Author: jbr
Date: Sun Aug 3 23:42:43 2008
New Revision: 14527
Log:
Hardcode the table for ungrouping 3 values in 5 bits. It will be reused by
the E-AC-3 decoder.
Modified:
trunk/libavcodec/ac3dec.c
trunk/libavcodec/ac3dec_data.c
trunk/libavcodec/ac3dec_data.h
Modified: trunk/libavcodec/ac3dec.c
==============================================================================
--- trunk/libavcodec/ac3dec.c (original)
+++ trunk/libavcodec/ac3dec.c Sun Aug 3 23:42:43 2008
@@ -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 */
Modified: trunk/libavcodec/ac3dec_data.c
==============================================================================
--- trunk/libavcodec/ac3dec_data.c (original)
+++ trunk/libavcodec/ac3dec_data.c Sun Aug 3 23:42:43 2008
@@ -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,
Modified: trunk/libavcodec/ac3dec_data.h
==============================================================================
--- trunk/libavcodec/ac3dec_data.h (original)
+++ trunk/libavcodec/ac3dec_data.h Sun Aug 3 23:42:43 2008
@@ -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];
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