mp4 mux: avoid unnecessary conversion

modules/mux/mp4.c

@@ -1152,9 +1152,8 @@ static bo_t *GetStblBox(sout_mux_t *p_mux, mp4_stream_t *p_stream)
         i_timescale = CLOCK_FREQ;
 
     /* first, create quantified length */
-    int64_t i_dts = 0, i_dts_q = 0;
+    int64_t i_dts = 0, i_dts_deq = 0;
     for (unsigned i = 0 ; i < p_stream->i_entry_count; i++) {
-        int64_t i_dts_deq = i_dts_q * CLOCK_FREQ / (int64_t)i_timescale;
         int64_t i_delta = p_stream->entry[i].i_length + i_dts - i_dts_deq;
 
         i_dts += p_stream->entry[i].i_length;
@@ -1162,7 +1161,7 @@ static bo_t *GetStblBox(sout_mux_t *p_mux, mp4_stream_t *p_stream)
         p_stream->entry[i].i_length =
             i_delta * (int64_t)i_timescale / CLOCK_FREQ;
 
-        i_dts_q += p_stream->entry[i].i_length;
+        i_dts_deq += i_delta;
     }
     /* then write encoded table */
     unsigned i_index = 0;