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authorMichael Niedermayer <michaelni@gmx.at>2011-03-15 16:18:40 +0100
committerMichael Niedermayer <michaelni@gmx.at>2011-03-15 16:48:42 +0100
commit6947b0c42e0649f0c8355442d1732d642e467902 (patch)
treebffb2d72049108372cbe46273998f3790dc860f0 /libavcodec/ac3enc_fixed.c
parent27293b840ccae95ddb1f4d8af519e7962b0e373d (diff)
parentc76374c6db5f486672f9df223f43e4892bd655c9 (diff)
downloadffmpeg-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.c52
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]);
+ }
+ }
}