avcodec/mpegvideo: Don't use ScanTable where unnecessary

For the intra_[hv]_scantables, only ScanTable.permutated
is used, so one only needs to keep that.

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Reviewed-by: Peter Ross <pross@xvid.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

8 files changed, 38 insertions, 26 deletions

diff --git a/libavcodec/ituh263dec.c b/libavcodec/ituh263dec.c
index 200de8527e..2164cd7346 100644
--- a/libavcodec/ituh263dec.c
+++ b/libavcodec/ituh263dec.c
@@ -544,9 +544,9 @@ static int h263_decode_block(MpegEncContext * s, int16_t * block,
         i = 0;
         if (s->ac_pred) {
             if (s->h263_aic_dir)
-                scan_table = s->intra_v_scantable.permutated; /* left */
+                scan_table = s->permutated_intra_v_scantable; /* left */
             else
-                scan_table = s->intra_h_scantable.permutated; /* top */
+                scan_table = s->permutated_intra_h_scantable; /* top */
         }
     } else if (s->mb_intra) {
         /* DC coef */
diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
index c4f268c534..4ab558b46f 100644
--- a/libavcodec/mpeg4videodec.c
+++ b/libavcodec/mpeg4videodec.c
@@ -1327,9 +1327,9 @@ static inline int mpeg4_decode_block(Mpeg4DecContext *ctx, int16_t *block,
         }
         if (s->ac_pred) {
             if (dc_pred_dir == 0)
-                scan_table = s->intra_v_scantable.permutated;  /* left */
+                scan_table = s->permutated_intra_v_scantable;  /* left */
             else
-                scan_table = s->intra_h_scantable.permutated;  /* top */
+                scan_table = s->permutated_intra_h_scantable;  /* top */
         } else {
             scan_table = s->intra_scantable.permutated;
         }
@@ -3258,13 +3258,17 @@ static int decode_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb,
     if (s->alternate_scan) {
         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable,   ff_alternate_vertical_scan);
         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable,   ff_alternate_vertical_scan);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
+        ff_permute_scantable(s->permutated_intra_h_scantable, ff_alternate_vertical_scan,
+                             s->idsp.idct_permutation);
+        ff_permute_scantable(s->permutated_intra_v_scantable, ff_alternate_vertical_scan,
+                             s->idsp.idct_permutation);
     } else {
         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable,   ff_zigzag_direct);
         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable,   ff_zigzag_direct);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
+        ff_permute_scantable(s->permutated_intra_h_scantable, ff_alternate_horizontal_scan,
+                             s->idsp.idct_permutation);
+        ff_permute_scantable(s->permutated_intra_v_scantable, ff_alternate_vertical_scan,
+                             s->idsp.idct_permutation);
     }
 
     /* Skip at this point when only parsing since the remaining
@@ -3432,13 +3436,17 @@ static int decode_studio_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb)
     if (s->alternate_scan) {
         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable,   ff_alternate_vertical_scan);
         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable,   ff_alternate_vertical_scan);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
+        ff_permute_scantable(s->permutated_intra_h_scantable, ff_alternate_vertical_scan,
+                             s->idsp.idct_permutation);
+        ff_permute_scantable(s->permutated_intra_v_scantable, ff_alternate_vertical_scan,
+                             s->idsp.idct_permutation);
     } else {
         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable,   ff_zigzag_direct);
         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable,   ff_zigzag_direct);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
+        ff_permute_scantable(s->permutated_intra_h_scantable, ff_alternate_horizontal_scan,
+                             s->idsp.idct_permutation);
+        ff_permute_scantable(s->permutated_intra_v_scantable, ff_alternate_vertical_scan,
+                             s->idsp.idct_permutation);
     }
 
     mpeg4_load_default_matrices(s);
diff --git a/libavcodec/mpeg4videoenc.c b/libavcodec/mpeg4videoenc.c
index 8e6e35b927..77f960a262 100644
--- a/libavcodec/mpeg4videoenc.c
+++ b/libavcodec/mpeg4videoenc.c
@@ -175,7 +175,7 @@ static inline int decide_ac_pred(MpegEncContext *s, int16_t block[6][64],
                     ac_val1[i + 8] = level;
                 }
             }
-            st[n] = s->intra_h_scantable.permutated;
+            st[n] = s->permutated_intra_h_scantable;
         } else {
             const int xy = s->mb_x - 1 + s->mb_y * s->mb_stride;
             /* left prediction */
@@ -197,7 +197,7 @@ static inline int decide_ac_pred(MpegEncContext *s, int16_t block[6][64],
                     ac_val1[i + 8] = block[n][s->idsp.idct_permutation[i]];
                 }
             }
-            st[n] = s->intra_v_scantable.permutated;
+            st[n] = s->permutated_intra_v_scantable;
         }
 
         for (i = 63; i > 0; i--)  // FIXME optimize
diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index 4326f7f9a5..c436dc8001 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -357,8 +357,10 @@ av_cold void ff_mpv_idct_init(MpegEncContext *s)
         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
     }
-    ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
-    ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
+    ff_permute_scantable(s->permutated_intra_h_scantable, ff_alternate_horizontal_scan,
+                         s->idsp.idct_permutation);
+    ff_permute_scantable(s->permutated_intra_v_scantable, ff_alternate_vertical_scan,
+                         s->idsp.idct_permutation);
 }
 
 static int init_duplicate_context(MpegEncContext *s)
diff --git a/libavcodec/mpegvideo.h b/libavcodec/mpegvideo.h
index 6adf724dac..ccec0dd75f 100644
--- a/libavcodec/mpegvideo.h
+++ b/libavcodec/mpegvideo.h
@@ -82,8 +82,8 @@ typedef struct MpegEncContext {
      *          offsets used in ASM. */
 
     ScanTable intra_scantable;
-    ScanTable intra_h_scantable;
-    ScanTable intra_v_scantable;
+    uint8_t permutated_intra_h_scantable[64];
+    uint8_t permutated_intra_v_scantable[64];
 
     struct AVCodecContext *avctx;
     /* The following pointer is intended for codecs sharing code
diff --git a/libavcodec/msmpeg4.c b/libavcodec/msmpeg4.c
index 455436e9c4..3f5dc23130 100644
--- a/libavcodec/msmpeg4.c
+++ b/libavcodec/msmpeg4.c
@@ -150,9 +150,11 @@ av_cold void ff_msmpeg4_common_init(MpegEncContext *s)
 
     if(s->msmpeg4_version>=4){
         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable,   ff_wmv1_scantable[1]);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_wmv1_scantable[2]);
-        ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_wmv1_scantable[3]);
         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable,   ff_wmv1_scantable[0]);
+        ff_permute_scantable(s->permutated_intra_h_scantable, ff_wmv1_scantable[2],
+                             s->idsp.idct_permutation);
+        ff_permute_scantable(s->permutated_intra_v_scantable, ff_wmv1_scantable[3],
+                             s->idsp.idct_permutation);
     }
     //Note the default tables are set in common_init in mpegvideo.c
 
diff --git a/libavcodec/msmpeg4dec.c b/libavcodec/msmpeg4dec.c
index 05a7ed4db6..8e12e1aab2 100644
--- a/libavcodec/msmpeg4dec.c
+++ b/libavcodec/msmpeg4dec.c
@@ -687,9 +687,9 @@ int ff_msmpeg4_decode_block(MpegEncContext * s, int16_t * block,
         }
         if (s->ac_pred) {
             if (dc_pred_dir == 0)
-                scan_table = s->intra_v_scantable.permutated; /* left */
+                scan_table = s->permutated_intra_v_scantable; /* left */
             else
-                scan_table = s->intra_h_scantable.permutated; /* top */
+                scan_table = s->permutated_intra_h_scantable; /* top */
         } else {
             scan_table = s->intra_scantable.permutated;
         }
diff --git a/libavcodec/wmv2.c b/libavcodec/wmv2.c
index 07a5d14f90..543784c813 100644
--- a/libavcodec/wmv2.c
+++ b/libavcodec/wmv2.c
@@ -36,12 +36,12 @@ av_cold void ff_wmv2_common_init(MpegEncContext *s)
                                   w->wdsp.idct_perm);
     ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable,
                       ff_wmv1_scantable[1]);
-    ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable,
-                      ff_wmv1_scantable[2]);
-    ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable,
-                      ff_wmv1_scantable[3]);
     ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable,
                       ff_wmv1_scantable[0]);
+    ff_permute_scantable(s->permutated_intra_h_scantable, ff_wmv1_scantable[2],
+                         s->idsp.idct_permutation);
+    ff_permute_scantable(s->permutated_intra_v_scantable, ff_wmv1_scantable[3],
+                         s->idsp.idct_permutation);
     s->idsp.idct_put = w->wdsp.idct_put;
     s->idsp.idct_add = w->wdsp.idct_add;
     s->idsp.idct     = NULL;