diff options
| author | Michael Niedermayer <michaelni@gmx.at> | 2005-02-03 03:28:27 +0000 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2005-02-03 03:28:27 +0000 |
| commit | 44f1698a3824836d32708ae93e78ac1f2310a07e (patch) | |
| tree | 029a9f8bd6c0dd3bbb2fc72481cdb83a4e1c05d8 | |
| parent | 125d624610b77ea11dae166305c96c2ae6e665a9 (diff) | |
merge a few shifts into the dequantization, faster and more accurate, lets hope it doesnt overflow
Originally committed as revision 3930 to svn://svn.ffmpeg.org/ffmpeg/trunk
| -rw-r--r-- | libavcodec/mpegaudiodec.c | 35 |
1 files changed, 18 insertions, 17 deletions
diff --git a/libavcodec/mpegaudiodec.c b/libavcodec/mpegaudiodec.c index c3e9946290..aad6a9a627 100644 --- a/libavcodec/mpegaudiodec.c +++ b/libavcodec/mpegaudiodec.c @@ -405,7 +405,7 @@ static int decode_init(AVCodecContext * avctx) f = pow((double)(i/4), 4.0 / 3.0) * pow(2, (i&3)*0.25); fm = frexp(f, &e); m = FIXHR(fm*0.5); - e+= FRAC_BITS - 31; + e+= FRAC_BITS - 31 + 5; /* normalized to FRAC_BITS */ table_4_3_value[i] = m; @@ -951,12 +951,13 @@ static const int icos36[9] = { static void imdct12(int *out, int *in) { int in0, in1, in2, in3, in4, in5, t1, t2; - in0= in[0*3]<<5; - in1= (in[1*3] + in[0*3])<<5; - in2= (in[2*3] + in[1*3])<<5; - in3= (in[3*3] + in[2*3])<<5; - in4= (in[4*3] + in[3*3])<<5; - in5= (in[5*3] + in[4*3])<<5; + + in0= in[0*3]; + in1= in[1*3] + in[0*3]; + in2= in[2*3] + in[1*3]; + in3= in[3*3] + in[2*3]; + in4= in[4*3] + in[3*3]; + in5= in[5*3] + in[4*3]; in5 += in3; in3 += in1; @@ -1082,15 +1083,15 @@ static void imdct36(int *out, int *buf, int *in, int *win) s1 = MULL(t3 + t2, icos36[j]); s3 = MULL(t3 - t2, icos36[8 - j]); - t0 = (s0 + s1) << 5; - t1 = (s0 - s1) << 5; + t0 = s0 + s1; + t1 = s0 - s1; out[(9 + j)*SBLIMIT] = MULH(t1, win[9 + j]) + buf[9 + j]; out[(8 - j)*SBLIMIT] = MULH(t1, win[8 - j]) + buf[8 - j]; buf[9 + j] = MULH(t0, win[18 + 9 + j]); buf[8 - j] = MULH(t0, win[18 + 8 - j]); - t0 = (s2 + s3) << 5; - t1 = (s2 - s3) << 5; + t0 = s2 + s3; + t1 = s2 - s3; out[(9 + 8 - j)*SBLIMIT] = MULH(t1, win[9 + 8 - j]) + buf[9 + 8 - j]; out[( j)*SBLIMIT] = MULH(t1, win[ j]) + buf[ j]; buf[9 + 8 - j] = MULH(t0, win[18 + 9 + 8 - j]); @@ -1100,8 +1101,8 @@ static void imdct36(int *out, int *buf, int *in, int *win) s0 = tmp[16]; s1 = MULL(tmp[17], icos36[4]); - t0 = (s0 + s1) << 5; - t1 = (s0 - s1) << 5; + t0 = s0 + s1; + t1 = s0 - s1; out[(9 + 4)*SBLIMIT] = MULH(t1, win[9 + 4]) + buf[9 + 4]; out[(8 - 4)*SBLIMIT] = MULH(t1, win[8 - 4]) + buf[8 - 4]; buf[9 + 4] = MULH(t0, win[18 + 9 + 4]); @@ -1920,11 +1921,11 @@ static void compute_antialias_integer(MPADecodeContext *s, int tmp0, tmp1, tmp2; csa = &csa_table[0][0]; #define INT_AA(j) \ - tmp0 = 4*(ptr[-1-j]);\ - tmp1 = 4*(ptr[ j]);\ + tmp0 = ptr[-1-j];\ + tmp1 = ptr[ j];\ tmp2= MULH(tmp0 + tmp1, csa[0+4*j]);\ - ptr[-1-j] = tmp2 - MULH(tmp1, csa[2+4*j]);\ - ptr[ j] = tmp2 + MULH(tmp0, csa[3+4*j]); + ptr[-1-j] = 4*(tmp2 - MULH(tmp1, csa[2+4*j]));\ + ptr[ j] = 4*(tmp2 + MULH(tmp0, csa[3+4*j])); INT_AA(0) INT_AA(1) |