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libavcodec/ppc/mpegaudiodec_altivec.c

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00001 /*
00002  * Altivec optimized MP3 decoding functions
00003  * Copyright (c) 2010 Vitor Sessak
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "dsputil_altivec.h"
00023 #include "util_altivec.h"
00024 #include "libavcodec/dsputil.h"
00025 #include "libavcodec/mpegaudiodsp.h"
00026 
00027 #define MACS(rt, ra, rb) rt+=(ra)*(rb)
00028 #define MLSS(rt, ra, rb) rt-=(ra)*(rb)
00029 
00030 #define SUM8(op, sum, w, p)               \
00031 {                                         \
00032     op(sum, (w)[0 * 64], (p)[0 * 64]);    \
00033     op(sum, (w)[1 * 64], (p)[1 * 64]);    \
00034     op(sum, (w)[2 * 64], (p)[2 * 64]);    \
00035     op(sum, (w)[3 * 64], (p)[3 * 64]);    \
00036     op(sum, (w)[4 * 64], (p)[4 * 64]);    \
00037     op(sum, (w)[5 * 64], (p)[5 * 64]);    \
00038     op(sum, (w)[6 * 64], (p)[6 * 64]);    \
00039     op(sum, (w)[7 * 64], (p)[7 * 64]);    \
00040 }
00041 
00042 static void apply_window(const float *buf, const float *win1,
00043                          const float *win2, float *sum1, float *sum2, int len)
00044 {
00045     const vector float *win1a = (const vector float *) win1;
00046     const vector float *win2a = (const vector float *) win2;
00047     const vector float *bufa  = (const vector float *) buf;
00048     vector float *sum1a = (vector float *) sum1;
00049     vector float *sum2a = (vector float *) sum2;
00050     vector float av_uninit(v0), av_uninit(v4);
00051     vector float v1, v2, v3;
00052 
00053     len = len >> 2;
00054 
00055 #define MULT(a, b)                         \
00056     {                                      \
00057         v1 = vec_ld(a, win1a);             \
00058         v2 = vec_ld(b, win2a);             \
00059         v3 = vec_ld(a, bufa);              \
00060         v0 = vec_madd(v3, v1, v0);         \
00061         v4 = vec_madd(v2, v3, v4);         \
00062     }
00063 
00064     while (len--) {
00065         v0 = vec_xor(v0, v0);
00066         v4 = vec_xor(v4, v4);
00067 
00068         MULT(   0,   0);
00069         MULT( 256,  64);
00070         MULT( 512, 128);
00071         MULT( 768, 192);
00072         MULT(1024, 256);
00073         MULT(1280, 320);
00074         MULT(1536, 384);
00075         MULT(1792, 448);
00076 
00077         vec_st(v0, 0, sum1a);
00078         vec_st(v4, 0, sum2a);
00079         sum1a++;
00080         sum2a++;
00081         win1a++;
00082         win2a++;
00083         bufa++;
00084     }
00085 }
00086 
00087 static void apply_window_mp3(float *in, float *win, int *unused, float *out,
00088                              int incr)
00089 {
00090     LOCAL_ALIGNED_16(float, suma, [17]);
00091     LOCAL_ALIGNED_16(float, sumb, [17]);
00092     LOCAL_ALIGNED_16(float, sumc, [17]);
00093     LOCAL_ALIGNED_16(float, sumd, [17]);
00094 
00095     float sum;
00096     int j;
00097     float *out2 = out + 32 * incr;
00098 
00099     /* copy to avoid wrap */
00100     memcpy(in + 512, in, 32 * sizeof(*in));
00101 
00102     apply_window(in + 16, win     , win + 512, suma, sumc, 16);
00103     apply_window(in + 32, win + 48, win + 640, sumb, sumd, 16);
00104 
00105     SUM8(MLSS, suma[0], win + 32, in + 48);
00106 
00107     sumc[ 0] = 0;
00108     sumb[16] = 0;
00109     sumd[16] = 0;
00110 
00111     out[0  ]  = suma[   0];
00112     out += incr;
00113     out2 -= incr;
00114     for(j=1;j<16;j++) {
00115         *out  =  suma[   j] - sumd[16-j];
00116         *out2 = -sumb[16-j] - sumc[   j];
00117         out  += incr;
00118         out2 -= incr;
00119     }
00120 
00121     sum = 0;
00122     SUM8(MLSS, sum, win + 16 + 32, in + 32);
00123     *out = sum;
00124 }
00125 
00126 void ff_mpadsp_init_altivec(MPADSPContext *s)
00127 {
00128     s->apply_window_float = apply_window_mp3;
00129 }
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