shithub: libvpx

Download patch

ref: 88a4d4c5109ce53680fc5b4f5104efd7d0c1994e
parent: 3d4e032e16a9252de6ea378924f8bf678dbeafd1
author: Sami Pietila <samipietila@google.com>
date: Thu May 23 09:08:00 EDT 2013 

Residual coding to cache energy class of tokens.

Proposal for tuning the residual coding by changing how the context
from previous tokens is calculated. Storing the energy class of previous
tokens instead of the token itself eases the critical path of
HW implementations.

Change-Id: I6d71d856b84518f6c88de771ddd818436f794bab


--- a/vp9/common/vp9_entropy.c
+++ b/vp9/common/vp9_entropy.c
@@ -468,7 +468,7 @@
     } else {
       ctx = token_cache[scan[neighbors[MAX_NEIGHBORS * c + 0]]];
     }
-    return vp9_pt_energy_class[ctx];
+    return ctx;
   }
 };
 
--- a/vp9/decoder/vp9_detokenize.c
+++ b/vp9/decoder/vp9_detokenize.c
@@ -58,6 +58,8 @@
   254, 254, 254, 252, 249, 243, 230, 196, 177, 153, 140, 133, 130, 129, 0
 };
 
+DECLARE_ALIGNED(16, extern const uint8_t,
+                vp9_pt_energy_class[MAX_ENTROPY_TOKENS]);
 #define INCREMENT_COUNT(token)               \
   do {                                       \
     coef_counts[type][ref][band][pt]         \
@@ -64,7 +66,7 @@
                [token >= TWO_TOKEN ?     \
                 (token == DCT_EOB_TOKEN ? DCT_EOB_MODEL_TOKEN : TWO_TOKEN) : \
                 token]++;     \
-    token_cache[scan[c]] = token; \
+    token_cache[scan[c]] = vp9_pt_energy_class[token]; \
   } while (0)
 
 #define WRITE_COEF_CONTINUE(val, token)                  \
--- a/vp9/encoder/vp9_encodemb.c
+++ b/vp9/encoder/vp9_encodemb.c
@@ -20,6 +20,9 @@
 #include "vp9/common/vp9_systemdependent.h"
 #include "vp9_rtcd.h"
 
+DECLARE_ALIGNED(16, extern const uint8_t,
+                vp9_pt_energy_class[MAX_ENTROPY_TOKENS]);
+
 void vp9_subtract_block(int rows, int cols,
                         int16_t *diff_ptr, int diff_stride,
                         const uint8_t *src_ptr, int src_stride,
@@ -105,7 +108,7 @@
                                      uint8_t *token_cache,
                                      int pad, int l) {
   int bak = token_cache[scan[idx]], pt;
-  token_cache[scan[idx]] = token;
+  token_cache[scan[idx]] = vp9_pt_energy_class[token];
   pt = vp9_get_coef_context(scan, nb, pad, token_cache, idx + 1, l);
   token_cache[scan[idx]] = bak;
   return pt;
@@ -189,7 +192,8 @@
   *(tokens[eob] + 1) = *(tokens[eob] + 0);
   next = eob;
   for (i = 0; i < eob; i++)
-    token_cache[scan[i]] = vp9_dct_value_tokens_ptr[qcoeff_ptr[scan[i]]].token;
+    token_cache[scan[i]] = vp9_pt_energy_class[vp9_dct_value_tokens_ptr[
+        qcoeff_ptr[scan[i]]].token];
   nb = vp9_get_coef_neighbors_handle(scan, &pad);
 
   for (i = eob; i-- > i0;) {
--- a/vp9/encoder/vp9_rdopt.c
+++ b/vp9/encoder/vp9_rdopt.c
@@ -46,6 +46,9 @@
 /* Factor to weigh the rate for switchable interp filters */
 #define SWITCHABLE_INTERP_RATE_FACTOR 1
 
+DECLARE_ALIGNED(16, extern const uint8_t,
+                vp9_pt_energy_class[MAX_ENTROPY_TOKENS]);
+
 const MODE_DEFINITION vp9_mode_order[MAX_MODES] = {
   {ZEROMV,    LAST_FRAME,   NONE},
   {DC_PRED,   INTRA_FRAME,  NONE},
@@ -366,7 +369,7 @@
 
       if (!c || token_cache[scan[c - 1]])
         cost += vp9_cost_bit(coef_probs[band][pt][0], 1);
-      token_cache[scan[c]] = t;
+      token_cache[scan[c]] = vp9_pt_energy_class[t];
     }
     if (c < seg_eob) {
       if (c)
--- a/vp9/encoder/vp9_tokenize.c
+++ b/vp9/encoder/vp9_tokenize.c
@@ -36,6 +36,9 @@
 extern vp9_coeff_stats tree_update_hist_32x32[BLOCK_TYPES];
 #endif  /* ENTROPY_STATS */
 
+DECLARE_ALIGNED(16, extern const uint8_t,
+                vp9_pt_energy_class[MAX_ENTROPY_TOKENS]);
+
 static TOKENVALUE dct_value_tokens[DCT_MAX_VALUE * 2];
 const TOKENVALUE *vp9_dct_value_tokens_ptr;
 static int dct_value_cost[DCT_MAX_VALUE * 2];
@@ -228,7 +231,7 @@
       if (!t->skip_eob_node)
         ++cpi->common.fc.eob_branch_counts[tx_size][type][ref][band][pt];
     }
-    token_cache[scan[c]] = token;
+    token_cache[scan[c]] = vp9_pt_energy_class[token];
     ++t;
   } while (c < eob && ++c < seg_eob);
 
-- 
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