X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fmpegaudiodsp_template.c;h=97317967a20b92a1ac4f6c624802ad283de5237c;hb=30f7021aa0be2c978aefb73894b643c9bafbf51c;hp=e531f8a904b14ad2f5cc6e59ad608bfe64b50065;hpb=52b44e9d15c0ee3c118ed68a0c2c737a9eb50ae9;p=ffmpeg

diff --git a/libavcodec/mpegaudiodsp_template.c b/libavcodec/mpegaudiodsp_template.c
index e531f8a904b..97317967a20 100644
--- a/libavcodec/mpegaudiodsp_template.c
+++ b/libavcodec/mpegaudiodsp_template.c
@@ -22,6 +22,9 @@
 
 #include "libavutil/attributes.h"
 #include "libavutil/mem.h"
+#include "libavutil/mem_internal.h"
+#include "libavutil/thread.h"
+
 #include "dct32.h"
 #include "mathops.h"
 #include "mpegaudiodsp.h"
@@ -192,7 +195,7 @@ void RENAME(ff_mpa_synth_filter)(MPADSPContext *s, MPA_INT *synth_buf_ptr,
     *synth_buf_offset = offset;
 }
 
-av_cold void RENAME(ff_mpa_synth_init)(MPA_INT *window)
+static av_cold void mpa_synth_init(MPA_INT *window)
 {
     int i, j;
 
@@ -221,48 +224,17 @@ av_cold void RENAME(ff_mpa_synth_init)(MPA_INT *window)
             window[512+128+16*i+j] = window[64*i+48-j];
 }
 
-av_cold void RENAME(ff_init_mpadsp_tabs)(void)
+static av_cold void mpa_synth_window_init(void)
 {
-    int i, j;
-    /* compute mdct windows */
-    for (i = 0; i < 36; i++) {
-        for (j = 0; j < 4; j++) {
-            double d;
-
-            if (j == 2 && i % 3 != 1)
-                continue;
-
-            d = sin(M_PI * (i + 0.5) / 36.0);
-            if (j == 1) {
-                if      (i >= 30) d = 0;
-                else if (i >= 24) d = sin(M_PI * (i - 18 + 0.5) / 12.0);
-                else if (i >= 18) d = 1;
-            } else if (j == 3) {
-                if      (i <   6) d = 0;
-                else if (i <  12) d = sin(M_PI * (i -  6 + 0.5) / 12.0);
-                else if (i <  18) d = 1;
-            }
-            //merge last stage of imdct into the window coefficients
-            d *= 0.5 * IMDCT_SCALAR / cos(M_PI * (2 * i + 19) / 72);
-
-            if (j == 2)
-                RENAME(ff_mdct_win)[j][i/3] = FIXHR((d / (1<<5)));
-            else {
-                int idx = i < 18 ? i : i + (MDCT_BUF_SIZE/2 - 18);
-                RENAME(ff_mdct_win)[j][idx] = FIXHR((d / (1<<5)));
-            }
-        }
-    }
+    mpa_synth_init(RENAME(ff_mpa_synth_window));
+}
 
-    /* NOTE: we do frequency inversion adter the MDCT by changing
-        the sign of the right window coefs */
-    for (j = 0; j < 4; j++) {
-        for (i = 0; i < MDCT_BUF_SIZE; i += 2) {
-            RENAME(ff_mdct_win)[j + 4][i    ] =  RENAME(ff_mdct_win)[j][i    ];
-            RENAME(ff_mdct_win)[j + 4][i + 1] = -RENAME(ff_mdct_win)[j][i + 1];
-        }
-    }
+av_cold void RENAME(ff_mpa_synth_init)(void)
+{
+    static AVOnce init_static_once = AV_ONCE_INIT;
+    ff_thread_once(&init_static_once, mpa_synth_window_init);
 }
+
 /* cos(pi*i/18) */
 #define C1 FIXHR(0.98480775301220805936/2)
 #define C2 FIXHR(0.93969262078590838405/2)