Do not initialize ff_cos_* tables again in rdft_init, they are already

initialized by ff_fft_init and using different code can result in slightly
different values, in addition it crashes when the tables are hardcoded.
On amd64 this slightly changes qdm2 output.


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@20237 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavcodec/dsputil.h

@@ -840,7 +840,7 @@ typedef struct {
     int sign_convention;
 
     /* pre/post rotation tables */
-    FFTSample *tcos;
+    const FFTSample *tcos;
     FFTSample *tsin;
     FFTContext fft;
 } RDFTContext;

libavcodec/rdft.c

@@ -64,7 +64,6 @@ av_cold int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans)
     s->tcos = ff_cos_tabs[nbits-4];
     s->tsin = ff_sin_tabs[nbits-4]+(trans == RDFT || trans == IRIDFT)*(n>>2);
     for (i = 0; i < (n>>2); i++) {
-        s->tcos[i] = cos(i*theta);
         s->tsin[i] = sin(i*theta);
     }
     return 0;