diff options
Diffstat (limited to 'apps/codecs/libmad/layer3.c')
| -rw-r--r-- | apps/codecs/libmad/layer3.c | 64 |
1 files changed, 25 insertions, 39 deletions
diff --git a/apps/codecs/libmad/layer3.c b/apps/codecs/libmad/layer3.c index 539526a93c..2b66775502 100644 --- a/apps/codecs/libmad/layer3.c +++ b/apps/codecs/libmad/layer3.c @@ -327,12 +327,11 @@ unsigned char const pretab[22] = { * table for requantization * * rq_table[x].mantissa * 2^(rq_table[x].exponent) = x^(4/3) + * + * format rq_table: bit31-27=exponent bit26-0=mantissa */ static -struct fixedfloat { - unsigned long mantissa : 27; - unsigned short exponent : 5; -} const rq_table[8207] = { +unsigned long const rq_table[8207] = { # include "rq_table.dat" }; @@ -342,8 +341,7 @@ struct fixedfloat { * * root_table[3 + x] = 2^(x/4) */ -static -mad_fixed_t const root_table[7] = { +mad_fixed_t const root_table[7] ICONST_ATTR = { MAD_F(0x09837f05) /* 2^(-3/4) == 0.59460355750136 */, MAD_F(0x0b504f33) /* 2^(-2/4) == 0.70710678118655 */, MAD_F(0x0d744fcd) /* 2^(-1/4) == 0.84089641525371 */, @@ -361,16 +359,14 @@ mad_fixed_t const root_table[7] = { * cs[i] = 1 / sqrt(1 + c[i]^2) * ca[i] = c[i] / sqrt(1 + c[i]^2) */ -static -mad_fixed_t const cs[8] = { +mad_fixed_t const cs[8] ICONST_ATTR = { +MAD_F(0x0db84a81) /* +0.857492926 */, +MAD_F(0x0e1b9d7f) /* +0.881741997 */, +MAD_F(0x0f31adcf) /* +0.949628649 */, +MAD_F(0x0fbba815) /* +0.983314592 */, +MAD_F(0x0feda417) /* +0.995517816 */, +MAD_F(0x0ffc8fc8) /* +0.999160558 */, +MAD_F(0x0fff964c) /* +0.999899195 */, +MAD_F(0x0ffff8d3) /* +0.999993155 */ }; -static -mad_fixed_t const ca[8] = { +mad_fixed_t const ca[8] ICONST_ATTR = { -MAD_F(0x083b5fe7) /* -0.514495755 */, -MAD_F(0x078c36d2) /* -0.471731969 */, -MAD_F(0x05039814) /* -0.313377454 */, -MAD_F(0x02e91dd1) /* -0.181913200 */, -MAD_F(0x0183603a) /* -0.094574193 */, -MAD_F(0x00a7cb87) /* -0.040965583 */, @@ -881,14 +877,15 @@ mad_fixed_t III_requantize(unsigned int value, signed int exp) { mad_fixed_t requantized; signed int frac; - struct fixedfloat const *power; + unsigned long power; frac = exp % 4; /* assumes sign(frac) == sign(exp) */ exp /= 4; - power = &rq_table[value]; - requantized = power->mantissa; - exp += power->exponent; + /* format rq_table: bit31-27=exponent bit26-0=mantissa */ + power = rq_table[value]; + requantized = power & 0x07ffffff; + exp += power >> 27; if (exp < 0) { if (-exp >= (signed int) (sizeof(mad_fixed_t) * CHAR_BIT)) { @@ -963,7 +960,7 @@ enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], unsigned int region, rcount; struct hufftable const *entry; union huffpair const *table; - unsigned int linbits, startbits, big_values, reqhits; + unsigned int linbits, startbits, big_values; mad_fixed_t reqcache[16]; sfbound = xrptr + *sfbwidth++; @@ -979,7 +976,9 @@ enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], expptr = &exponents[0]; exp = *expptr++; - reqhits = 0; + + /* clear cache */ + memset(reqcache, 0, sizeof(reqcache)); big_values = channel->big_values; @@ -1010,7 +1009,7 @@ enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], if (exp != *expptr) { exp = *expptr; - reqhits = 0; + memset(reqcache, 0, sizeof(reqcache)); } ++expptr; @@ -1063,12 +1062,10 @@ enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], goto x_final; default: - if (reqhits & (1 << value)) + if (reqcache[value]) requantized = reqcache[value]; - else { - reqhits |= (1 << value); + else requantized = reqcache[value] = III_requantize(value, exp); - } x_final: xrptr[0] = MASK1BIT(bitcache, cachesz--) ? @@ -1098,12 +1095,10 @@ enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], goto y_final; default: - if (reqhits & (1 << value)) + if (reqcache[value]) requantized = reqcache[value]; - else { - reqhits |= (1 << value); + else requantized = reqcache[value] = III_requantize(value, exp); - } y_final: xrptr[1] = MASK1BIT(bitcache, cachesz--) ? @@ -1118,12 +1113,10 @@ enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], if (value == 0) xrptr[0] = 0; else { - if (reqhits & (1 << value)) + if (reqcache[value]) requantized = reqcache[value]; - else { - reqhits |= (1 << value); + else requantized = reqcache[value] = III_requantize(value, exp); - } xrptr[0] = MASK1BIT(bitcache, cachesz--) ? -requantized : requantized; @@ -1136,12 +1129,10 @@ enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], if (value == 0) xrptr[1] = 0; else { - if (reqhits & (1 << value)) + if (reqcache[value]) requantized = reqcache[value]; - else { - reqhits |= (1 << value); + else requantized = reqcache[value] = III_requantize(value, exp); - } xrptr[1] = MASK1BIT(bitcache, cachesz--) ? -requantized : requantized; @@ -1257,12 +1248,7 @@ enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], # endif /* rzero */ - while (xrptr < &xr[576]) { - xrptr[0] = 0; - xrptr[1] = 0; - - xrptr += 2; - } + memset(xrptr, 0, (char*)&xr[576] - (char*)xrptr); return MAD_ERROR_NONE; } |