Implement update_txb_context for lv_map

Change-Id: I6bedc3a1a40e551ce4b3989382b7706a589c08f2

av1/encoder/encodetxb.c

diff --git a/av1/encoder/encodetxb.c b/av1/encoder/encodetxb.c
index bf0ad2a..a7e4e71 100644
--- a/av1/encoder/encodetxb.c
+++ b/av1/encoder/encodetxb.c
@@ -378,14 +378,35 @@
                                BLOCK_SIZE plane_bsize, TX_SIZE tx_size,
                                void *arg) {
   TxbParams *const args = arg;
+  const AV1_COMP *cpi = args->cpi;
+  const AV1_COMMON *cm = &cpi->common;
   ThreadData *const td = args->td;
   MACROBLOCK *const x = &td->mb;
   MACROBLOCKD *const xd = &x->e_mbd;
+  MB_MODE_INFO *mbmi = &xd->mi[0]->mbmi;
   struct macroblock_plane *p = &x->plane[plane];
   struct macroblockd_plane *pd = &xd->plane[plane];
+  const uint16_t eob = p->eobs[block];
+  const tran_low_t *qcoeff = BLOCK_OFFSET(p->qcoeff, block);
+  const PLANE_TYPE plane_type = pd->plane_type;
+  const TX_TYPE tx_type = get_tx_type(plane_type, xd, block, tx_size);
+  const SCAN_ORDER *const scan_order =
+      get_scan(cm, tx_size, tx_type, is_inter_block(mbmi));
+  const int16_t *scan = scan_order->scan;
   (void)plane_bsize;
-  av1_set_contexts(xd, pd, plane, tx_size, p->eobs[block] > 0, blk_col,
-                   blk_row);
+
+  int cul_level = 0;
+  int c;
+  for (c = 0; c < eob; ++c) {
+    cul_level += abs(qcoeff[scan[c]]);
+  }
+
+  cul_level = AOMMIN(COEFF_CONTEXT_MASK, cul_level);
+
+  // DC value
+  set_dc_sign(&cul_level, qcoeff[0]);
+
+  av1_set_contexts(xd, pd, plane, tx_size, cul_level, blk_col, blk_row);
 }
 
 static void update_and_record_txb_context(int plane, int block, int blk_row,
@@ -508,7 +529,8 @@
 
     // use 0-th order Golomb code to handle the residual level.
   }
-  cul_level = AOMMIN(63, cul_level);
+
+  cul_level = AOMMIN(COEFF_CONTEXT_MASK, cul_level);
 
   // DC value
   set_dc_sign(&cul_level, tcoeff[0]);