h261, h263 decoders: convert to RL_VLC.

Some additional optimizations in following patch.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>

1 files changed, 43 insertions, 15 deletions

diff --git a/libavcodec/ituh263dec.c b/libavcodec/ituh263dec.c
index e64c2bb769..c481621fd2 100644
--- a/libavcodec/ituh263dec.c
+++ b/libavcodec/ituh263dec.c
@@ -418,7 +418,7 @@ static void h263_decode_dquant(MpegEncContext *s){
 static int h263_decode_block(MpegEncContext * s, int16_t * block,
                              int n, int coded)
 {
-    int code, level, i, j, last, run;
+    int level, i, j, last, run;
     RLTable *rl = &ff_h263_rl_inter;
     const uint8_t *scan_table;
     GetBitContext gb= s->gb;
@@ -479,40 +479,66 @@ static int h263_decode_block(MpegEncContext * s, int16_t * block,
         return 0;
     }
 retry:
+    {
+    OPEN_READER(re, &s->gb);
     for(;;) {
-        code = get_vlc2(&s->gb, rl->vlc.table, TEX_VLC_BITS, 2);
-        if (code < 0){
+        UPDATE_CACHE(re, &s->gb);
+        GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
+        if (run == 66 && level){
             av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y);
             return -1;
         }
-        if (code == rl->n) {
+        if (run == 66) {
             /* escape */
             if (CONFIG_FLV_DECODER && s->h263_flv > 1) {
-                ff_flv2_decode_ac_esc(&s->gb, &level, &run, &last);
+                int is11 = SHOW_UBITS(re, &s->gb, 1);
+                SKIP_CACHE(re, &s->gb, 1);
+                last = SHOW_UBITS(re, &s->gb, 1);
+                SKIP_CACHE(re, &s->gb, 1);
+                run = SHOW_UBITS(re, &s->gb, 6);
+                if (is11) {
+                    SKIP_COUNTER(re, &s->gb, 6);
+                    UPDATE_CACHE(re, &s->gb);
+                    level = SHOW_SBITS(re, &s->gb, 11);
+                    SKIP_COUNTER(re, &s->gb, 1 + 1 + 6 + 11);
+                } else {
+                    SKIP_CACHE(re, &s->gb, 6);
+                    level = SHOW_SBITS(re, &s->gb, 7);
+                    SKIP_COUNTER(re, &s->gb, 1 + 1 + 6 + 7);
+                }
             } else {
-                last = get_bits1(&s->gb);
-                run = get_bits(&s->gb, 6);
-                level = (int8_t)get_bits(&s->gb, 8);
+                last = SHOW_UBITS(re, &s->gb, 1);
+                SKIP_CACHE(re, &s->gb, 1);
+                run = SHOW_UBITS(re, &s->gb, 6);
+                SKIP_CACHE(re, &s->gb, 6);
+                level = (int8_t)SHOW_UBITS(re, &s->gb, 8);
+                SKIP_COUNTER(re, &s->gb, 1 + 6 + 8);
                 if(level == -128){
+                    UPDATE_CACHE(re, &s->gb);
                     if (s->codec_id == AV_CODEC_ID_RV10) {
                         /* XXX: should patch encoder too */
-                        level = get_sbits(&s->gb, 12);
+                        level = SHOW_SBITS(re, &s->gb, 12);
+                        SKIP_COUNTER(re, &s->gb, 12);
                     }else{
-                        level = get_bits(&s->gb, 5);
-                        level |= get_sbits(&s->gb, 6)<<5;
+                        level = SHOW_UBITS(re, &s->gb, 5);
+                        SKIP_CACHE(re, &s->gb, 5);
+                        level |= SHOW_SBITS(re, &s->gb, 6)<<5;
+                        SKIP_COUNTER(re, &s->gb, 5 + 6);
                     }
                 }
             }
         } else {
-            run = rl->table_run[code];
-            level = rl->table_level[code];
-            last = code >= rl->last;
-            if (get_bits1(&s->gb))
+            run--;
+            last = run >= 192;
+            run &= 63;
+            if (SHOW_UBITS(re, &s->gb, 1))
                 level = -level;
+            SKIP_COUNTER(re, &s->gb, 1);
         }
         i += run;
         if (i >= 64){
             if(s->alt_inter_vlc && rl == &ff_h263_rl_inter && !s->mb_intra){
+                CLOSE_READER(re, &s->gb);
                 //Looks like a hack but no, it's the way it is supposed to work ...
                 rl = &ff_rl_intra_aic;
                 i = 0;
@@ -529,6 +555,8 @@ retry:
             break;
         i++;
     }
+    CLOSE_READER(re, &s->gb);
+    }
 not_coded:
     if (s->mb_intra && s->h263_aic) {
         ff_h263_pred_acdc(s, block, n);