[FFmpeg-devel,v2,058/162] avcodec/mpegaudiodsp: Make initializing synth windows thread-safe

diff --git a/libavcodec/mpc.c b/libavcodec/mpc.c
index e56b608d8c..e29b823460 100644
--- a/libavcodec/mpc.c
+++ b/libavcodec/mpc.c
@@ -34,11 +34,6 @@ 
 #include "mpc.h"
 #include "mpcdata.h"
 
-av_cold void ff_mpc_init(void)
-{
-    ff_mpa_synth_init_fixed(ff_mpa_synth_window_fixed);
-}
-
 /**
  * Process decoded Musepack data and produce PCM
  */
diff --git a/libavcodec/mpc.h b/libavcodec/mpc.h
index df462af6b7..704edc9a38 100644
--- a/libavcodec/mpc.h
+++ b/libavcodec/mpc.h
@@ -70,7 +70,6 @@  typedef struct MPCContext {
     DECLARE_ALIGNED(16, int32_t, sb_samples)[MPA_MAX_CHANNELS][36][SBLIMIT];
 } MPCContext;
 
-void ff_mpc_init(void);
 void ff_mpc_dequantize_and_synth(MPCContext *c, int maxband, int16_t **out, int channels);
 
 #endif /* AVCODEC_MPC_H */
diff --git a/libavcodec/mpc7.c b/libavcodec/mpc7.c
index 0b9e6f0088..b067d77c4b 100644
--- a/libavcodec/mpc7.c
+++ b/libavcodec/mpc7.c
@@ -64,7 +64,6 @@  static av_cold int mpc7_decode_init(AVCodecContext * avctx)
     ff_bswapdsp_init(&c->bdsp);
     ff_mpadsp_init(&c->mpadsp);
     c->bdsp.bswap_buf((uint32_t *) buf, (const uint32_t *) avctx->extradata, 4);
-    ff_mpc_init();
     init_get_bits(&gb, buf, 128);
 
     c->IS = get_bits1(&gb);
@@ -109,6 +108,7 @@  static av_cold int mpc7_decode_init(AVCodecContext * avctx)
         }
     }
     vlc_initialized = 1;
+    ff_mpa_synth_init_fixed();
 
     return 0;
 }
diff --git a/libavcodec/mpc8.c b/libavcodec/mpc8.c
index b36e47ce66..c263762c8b 100644
--- a/libavcodec/mpc8.c
+++ b/libavcodec/mpc8.c
@@ -126,8 +126,6 @@  static av_cold int mpc8_decode_init(AVCodecContext * avctx)
     av_lfg_init(&c->rnd, 0xDEADBEEF);
     ff_mpadsp_init(&c->mpadsp);
 
-    ff_mpc_init();
-
     init_get_bits(&gb, avctx->extradata, 16);
 
     skip_bits(&gb, 3);//sample rate
@@ -171,6 +169,7 @@  static av_cold int mpc8_decode_init(AVCodecContext * avctx)
                       &q_syms, -((8 << j) - 1));
     }
     vlc_initialized = 1;
+    ff_mpa_synth_init_fixed();
 
     return 0;
 }
diff --git a/libavcodec/mpegaudiodec_template.c b/libavcodec/mpegaudiodec_template.c
index 12c1964446..849e3e5c09 100644
--- a/libavcodec/mpegaudiodec_template.c
+++ b/libavcodec/mpegaudiodec_template.c
@@ -289,8 +289,6 @@  static av_cold void decode_init_static(void)
                 scale_factor_mult[i][2]);
     }
 
-    RENAME(ff_mpa_synth_init)(RENAME(ff_mpa_synth_window));
-
     /* huffman decode tables */
     offset = 0;
     for (i = 1; i < 16; i++) {
@@ -408,6 +406,7 @@  static av_cold void decode_init_static(void)
         csa_table[i][3] = ca - cs;
 #endif
     }
+    RENAME(ff_mpa_synth_init)();
 }
 
 static av_cold int decode_init(AVCodecContext * avctx)
diff --git a/libavcodec/mpegaudiodsp.h b/libavcodec/mpegaudiodsp.h
index 4c9b05ebac..4577d515d9 100644
--- a/libavcodec/mpegaudiodsp.h
+++ b/libavcodec/mpegaudiodsp.h
@@ -67,8 +67,8 @@  void ff_mpadsp_init_x86_tabs(void);
 void ff_mpadsp_init_mipsfpu(MPADSPContext *s);
 void ff_mpadsp_init_mipsdsp(MPADSPContext *s);
 
-void ff_mpa_synth_init_float(float *window);
-void ff_mpa_synth_init_fixed(int32_t *window);
+void ff_mpa_synth_init_float(void);
+void ff_mpa_synth_init_fixed(void);
 
 void ff_mpadsp_apply_window_float(float *synth_buf, float *window,
                                   int *dither_state, float *samples,
diff --git a/libavcodec/mpegaudiodsp_template.c b/libavcodec/mpegaudiodsp_template.c
index f8d0870df6..c67c456e8a 100644
--- a/libavcodec/mpegaudiodsp_template.c
+++ b/libavcodec/mpegaudiodsp_template.c
@@ -22,6 +22,7 @@ 
 
 #include "libavutil/attributes.h"
 #include "libavutil/mem.h"
+#include "libavutil/thread.h"
 #include "dct32.h"
 #include "mathops.h"
 #include "mpegaudiodsp.h"
@@ -192,7 +193,7 @@  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;
 
@@ -221,6 +222,17 @@  av_cold void RENAME(ff_mpa_synth_init)(MPA_INT *window)
             window[512+128+16*i+j] = window[64*i+48-j];
 }
 
+static av_cold void mpa_synth_window_init(void)
+{
+    mpa_synth_init(RENAME(ff_mpa_synth_window));
+}
+
+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)
diff --git a/libavcodec/qdm2.c b/libavcodec/qdm2.c
index 657b2da64d..bd365739ce 100644
--- a/libavcodec/qdm2.c
+++ b/libavcodec/qdm2.c
@@ -1604,11 +1604,12 @@  static av_cold void qdm2_init_static_data(void) {
         return;
 
     qdm2_init_vlc();
-    ff_mpa_synth_init_float(ff_mpa_synth_window_float);
     softclip_table_init();
     rnd_table_init();
     init_noise_samples();
 
+    ff_mpa_synth_init_float();
+
     done = 1;
 }