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author | Michael Niedermayer <michaelni@gmx.at> | 2011-03-15 16:18:40 +0100 |
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committer | Michael Niedermayer <michaelni@gmx.at> | 2011-03-15 16:48:42 +0100 |
commit | 6947b0c42e0649f0c8355442d1732d642e467902 (patch) | |
tree | bffb2d72049108372cbe46273998f3790dc860f0 /libavcodec/ac3enc_fixed.c | |
parent | 27293b840ccae95ddb1f4d8af519e7962b0e373d (diff) | |
parent | c76374c6db5f486672f9df223f43e4892bd655c9 (diff) | |
download | ffmpeg-6947b0c42e0649f0c8355442d1732d642e467902.tar.gz |
Merge remote-tracking branch 'newdev/master'
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/ac3enc_fixed.c')
-rw-r--r-- | libavcodec/ac3enc_fixed.c | 52 |
1 files changed, 21 insertions, 31 deletions
diff --git a/libavcodec/ac3enc_fixed.c b/libavcodec/ac3enc_fixed.c index 3de00ee484..d1bb429ccc 100644 --- a/libavcodec/ac3enc_fixed.c +++ b/libavcodec/ac3enc_fixed.c @@ -131,10 +131,10 @@ mdct_alloc_fail: /** Complex multiply */ -#define CMUL(pre, pim, are, aim, bre, bim) \ +#define CMUL(pre, pim, are, aim, bre, bim, rshift) \ { \ - pre = (MUL16(are, bre) - MUL16(aim, bim)) >> 15; \ - pim = (MUL16(are, bim) + MUL16(bre, aim)) >> 15; \ + pre = (MUL16(are, bre) - MUL16(aim, bim)) >> rshift; \ + pim = (MUL16(are, bim) + MUL16(bre, aim)) >> rshift; \ } @@ -195,7 +195,7 @@ static void fft(AC3MDCTContext *mdct, IComplex *z, int ln) p++; q++; for(l = nblocks; l < np2; l += nblocks) { - CMUL(tmp_re, tmp_im, mdct->costab[l], -mdct->sintab[l], q->re, q->im); + CMUL(tmp_re, tmp_im, mdct->costab[l], -mdct->sintab[l], q->re, q->im, 15); BF(p->re, p->im, q->re, q->im, p->re, p->im, tmp_re, tmp_im); p++; @@ -234,7 +234,7 @@ static void mdct512(AC3MDCTContext *mdct, int32_t *out, int16_t *in) for (i = 0; i < n4; i++) { re = ((int)rot[ 2*i] - (int)rot[ n-1-2*i]) >> 1; im = -((int)rot[n2+2*i] - (int)rot[n2-1-2*i]) >> 1; - CMUL(x[i].re, x[i].im, re, im, -mdct->xcos1[i], mdct->xsin1[i]); + CMUL(x[i].re, x[i].im, re, im, -mdct->xcos1[i], mdct->xsin1[i], 15); } fft(mdct, x, mdct->nbits - 2); @@ -243,7 +243,7 @@ static void mdct512(AC3MDCTContext *mdct, int32_t *out, int16_t *in) for (i = 0; i < n4; i++) { re = x[i].re; im = x[i].im; - CMUL(out[n2-1-2*i], out[2*i], re, im, mdct->xsin1[i], mdct->xcos1[i]); + CMUL(out[n2-1-2*i], out[2*i], re, im, mdct->xsin1[i], mdct->xcos1[i], 0); } } @@ -278,45 +278,35 @@ static int log2_tab(AC3EncodeContext *s, int16_t *src, int len) /** - * Left-shift each value in an array by a specified amount. - * @param tab input array - * @param n number of values in the array - * @param lshift left shift amount - */ -static void lshift_tab(int16_t *tab, int n, unsigned int lshift) -{ - int i; - - if (lshift > 0) { - for (i = 0; i < n; i++) - tab[i] <<= lshift; - } -} - - -/** * Normalize the input samples to use the maximum available precision. - * This assumes signed 16-bit input samples. Exponents are reduced by 9 to - * match the 24-bit internal precision for MDCT coefficients. + * This assumes signed 16-bit input samples. * * @return exponent shift */ static int normalize_samples(AC3EncodeContext *s) { int v = 14 - log2_tab(s, s->windowed_samples, AC3_WINDOW_SIZE); - lshift_tab(s->windowed_samples, AC3_WINDOW_SIZE, v); - return v - 9; + if (v > 0) + s->ac3dsp.ac3_lshift_int16(s->windowed_samples, AC3_WINDOW_SIZE, v); + /* +6 to right-shift from 31-bit to 25-bit */ + return v + 6; } /** - * Scale MDCT coefficients from float to fixed-point. + * Scale MDCT coefficients to 25-bit signed fixed-point. */ static void scale_coefficients(AC3EncodeContext *s) { - /* scaling/conversion is obviously not needed for the fixed-point encoder - since the coefficients are already fixed-point. */ - return; + int blk, ch; + + for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) { + AC3Block *block = &s->blocks[blk]; + for (ch = 0; ch < s->channels; ch++) { + s->ac3dsp.ac3_rshift_int32(block->mdct_coef[ch], AC3_MAX_COEFS, + block->coeff_shift[ch]); + } + } } |