Replace rand() usage by av_lfg_get().

Originally committed as revision 18420 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/timefilter.c

@@ -76,9 +76,12 @@ double ff_timefilter_update(TimeFilter *self, double system_time, double period)
 }
 
 #ifdef TEST
-#undef rand
+#include "libavutil/lfg.h"
+#define LFG_MAX ((1LL << 32) - 1)
+
 int main(void)
 {
+    AVLFG prng;
     double n0,n1;
 #define SAMPLES 1000
     double ideal[SAMPLES];
@@ -96,10 +99,11 @@ int main(void)
             double bestpar1=0.001;
             int better, i;
 
-            srandom(123);
+            av_lfg_init(&prng, 123);
             for(i=0; i<SAMPLES; i++){
                 ideal[i]  = 10 + i + n1*i/(1000);
-                samples[i]= ideal[i] + n0*(rand()-RAND_MAX/2)/(RAND_MAX*10LL);
+                samples[i] = ideal[i] + n0 * (av_lfg_get(&prng) - LFG_MAX / 2)
+                                           / (LFG_MAX * 10LL);
             }
 
             do{