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Clean up fft_init() and mdct_init()

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Originally committed as revision 25959 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Justin Ruggles 2010-12-14 14:51:12 +00:00
parent 6a988808a4
commit b84a211bc8
1 changed files with 10 additions and 9 deletions
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19
libavcodec/ac3enc.c
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@ -93,13 +93,14 @@ typedef struct IComplex {
static av_cold void fft_init(int ln) static av_cold void fft_init(int ln)
{ {
int i, n; int i, n, n2;
float alpha; float alpha;
n = 1 << ln; n = 1 << ln;
n2 = n >> 1;
for (i = 0; i < n/2; i++) { for (i = 0; i < n2; i++) {
alpha = 2 * M_PI * (float)i / (float)n; alpha = 2.0 * M_PI * i / n;
costab[i] = FIX15(cos(alpha)); costab[i] = FIX15(cos(alpha));
sintab[i] = FIX15(sin(alpha)); sintab[i] = FIX15(sin(alpha));
} }
@ -107,15 +108,15 @@ static av_cold void fft_init(int ln)
static av_cold void mdct_init(int nbits) static av_cold void mdct_init(int nbits)
{ {
int i; int i, n, n4;
float alpha;
int n = 1 << nbits; n = 1 << nbits;
int n4 = n >> 2; n4 = n >> 2;
fft_init(nbits - 2); fft_init(nbits - 2);
for (i = 0; i < n4; i++) { for (i = 0; i < n4; i++) {
alpha = 2 * M_PI * (i + 1.0 / 8.0) / n; float alpha = 2.0 * M_PI * (i + 1.0 / 8.0) / n;
xcos1[i] = FIX15(-cos(alpha)); xcos1[i] = FIX15(-cos(alpha));
xsin1[i] = FIX15(-sin(alpha)); xsin1[i] = FIX15(-sin(alpha));
} }