diff --git a/av1/decoder/decodetxb.c b/av1/decoder/decodetxb.c
index 2317f95..f9d2f72 100644
--- a/av1/decoder/decodetxb.c
+++ b/av1/decoder/decodetxb.c
@@ -49,6 +49,21 @@
   return eob;
 }
 
+#if !CONFIG_NEW_QUANT
+static INLINE int get_dqv(const int16_t *dequant, int coeff_idx,
+                          const qm_val_t *iqmatrix) {
+  int dqv = dequant[!!coeff_idx];
+#if CONFIG_AOM_QM
+  if (iqmatrix != NULL)
+    dqv =
+        ((iqmatrix[coeff_idx] * dqv) + (1 << (AOM_QM_BITS - 1))) >> AOM_QM_BITS;
+#else
+  (void)iqmatrix;
+#endif
+  return dqv;
+}
+#endif
+
 uint8_t av1_read_coeffs_txb(const AV1_COMMON *const cm, MACROBLOCKD *const xd,
                             aom_reader *const r, const int blk_row,
                             const int blk_col, const int plane,
@@ -115,6 +130,16 @@
 #endif
   const TX_TYPE tx_type = av1_get_tx_type(plane_type, xd, blk_row, blk_col,
                                           tx_size, cm->reduced_tx_set_used);
+#if CONFIG_AOM_QM
+  const TX_SIZE qm_tx_size = av1_get_adjusted_tx_size(tx_size);
+  const qm_val_t *iqmatrix =
+      IS_2D_TRANSFORM(tx_type)
+          ? pd->seg_iqmatrix[mbmi->segment_id][qm_tx_size]
+          : cm->giqmatrix[NUM_QM_LEVELS - 1][0][qm_tx_size];
+#else
+  const qm_val_t *iqmatrix = NULL;
+#endif
+  (void)iqmatrix;
   const SCAN_ORDER *const scan_order = get_scan(cm, tx_size, tx_type, mbmi);
   const int16_t *const scan = scan_order->scan;
   int dummy;
@@ -229,7 +254,7 @@
         v = av1_dequant_abscoeff_nuq(level, dequant[!!c], dqv_val, nq_shift);
 #endif  // CONFIG_AOM_QM
 #else
-        v = level * dequant[!!c];
+        v = level * get_dqv(dequant, scan[c], iqmatrix);
         v = v >> shift;
 #endif  // CONFIG_NEW_QUANT
         tcoeffs[pos] = v;
@@ -288,7 +313,7 @@
         t = av1_dequant_abscoeff_nuq(*level, dequant[!!pos], dqv_val, nq_shift);
 #endif  // CONFIG_AOM_QM
 #else
-        t = *level * dequant[!!pos];
+        t = *level * get_dqv(dequant, pos, iqmatrix);
         t = t >> shift;
 #endif  // CONFIG_NEW_QUANT
         if (signs[pos]) t = -t;
@@ -309,7 +334,7 @@
       t = av1_dequant_abscoeff_nuq(t, dequant[!!pos], dqv_val, nq_shift);
 #endif  // CONFIG_AOM_QM
 #else
-      t = t * dequant[!!pos];
+      t = t * get_dqv(dequant, pos, iqmatrix);
       t = t >> shift;
 #endif  // CONFIG_NEW_QUANT
       if (signs[pos]) t = -t;
diff --git a/av1/encoder/encodetxb.c b/av1/encoder/encodetxb.c
index 89ebcb0..1ee5089 100644
--- a/av1/encoder/encodetxb.c
+++ b/av1/encoder/encodetxb.c
@@ -137,25 +137,30 @@
   return qc > 0 ? qc - 1 : qc + 1;
 }
 
-static INLINE tran_low_t qcoeff_to_dqcoeff(tran_low_t qc,
+static INLINE tran_low_t qcoeff_to_dqcoeff(tran_low_t qc, int coeff_idx,
 #if CONFIG_NEW_QUANT
 #if CONFIG_AOM_QM
-                                           int dq_idx, int is_ac_coeff,
+                                           int dq_idx,
 #else
                                            const tran_low_t *nq_dq,
 #endif  // CONFIG_AOM_QM
 #endif  // CONFIG_NEW_QUANT
-                                           int dqv, int shift) {
+                                           int dqv, int shift,
+                                           const qm_val_t *iqmatrix) {
   int sgn = qc < 0 ? -1 : 1;
 #if CONFIG_NEW_QUANT
 #if CONFIG_AOM_QM
+  int is_ac_coeff = coeff_idx != 0;
   int dqcoeff = av1_dequant_coeff_nuq(abs(qc), dqv, dq_idx, is_ac_coeff, shift);
 #else
+  (void)coeff_idx;
   int dqcoeff = av1_dequant_coeff_nuq(abs(qc), dqv, nq_dq, shift);
 #endif  // CONFIG_AOM_QM
   return sgn * dqcoeff;
 #endif  // CONFIG_NEW_QUANT
-
+  if (iqmatrix != NULL)
+    dqv =
+        ((iqmatrix[coeff_idx] * dqv) + (1 << (AOM_QM_BITS - 1))) >> AOM_QM_BITS;
   return sgn * ((abs(qc) * dqv) >> shift);
 }
 
@@ -299,27 +304,29 @@
     stats->rate = qc_cost;
     return;
   } else {
-    const tran_low_t dqc = qcoeff_to_dqcoeff(qc,
+    const tran_low_t dqc =
+        qcoeff_to_dqcoeff(qc, coeff_idx,
 #if CONFIG_NEW_QUANT
 #if CONFIG_AOM_QM
-                                             dq_idx, coeff_idx != 0,
+                          dq_idx,
 #else
-                                             nq_dequant_val,
+                          nq_dequant_val,
 #endif  // CONFIG_AOM_QM
 #endif  // CONFIG_NEW_QUANT
-                                             dqv, txb_info->shift);
+                          dqv, txb_info->shift, txb_info->iqmatrix);
     const int64_t dqc_dist = get_coeff_dist(tqc, dqc, txb_info->shift);
 
     // distortion difference when coefficient is quantized to 0
-    const tran_low_t dqc0 = qcoeff_to_dqcoeff(0,
+    const tran_low_t dqc0 =
+        qcoeff_to_dqcoeff(0, coeff_idx,
 #if CONFIG_NEW_QUANT
 #if CONFIG_AOM_QM
-                                              dq_idx, coeff_idx != 0,
+                          dq_idx,
 #else
-                                              nq_dequant_val,
+                          nq_dequant_val,
 #endif  // CONFIG_AOM_QM
 #endif  // CONFIG_NEW_QUANT
-                                              dqv, txb_info->shift);
+                          dqv, txb_info->shift, txb_info->iqmatrix);
 
     stats->dist0 = get_coeff_dist(tqc, dqc0, txb_info->shift);
     stats->dist = dqc_dist - stats->dist0;
@@ -336,15 +343,16 @@
     if (stats->low_qc == 0) {
       stats->dist_low = 0;
     } else {
-      stats->low_dqc = qcoeff_to_dqcoeff(stats->low_qc,
+      stats->low_dqc =
+          qcoeff_to_dqcoeff(stats->low_qc, coeff_idx,
 #if CONFIG_NEW_QUANT
 #if CONFIG_AOM_QM
-                                         dq_idx, coeff_idx != 0,
+                            dq_idx,
 #else
-                                         nq_dequant_val,
+                            nq_dequant_val,
 #endif  // CONFIG_AOM_QM
 #endif  // CONFIG_NEW_QUANT
-                                         dqv, txb_info->shift);
+                            dqv, txb_info->shift, txb_info->iqmatrix);
       const int64_t low_dqc_dist =
           get_coeff_dist(tqc, stats->low_dqc, txb_info->shift);
       stats->dist_low = low_dqc_dist - stats->dist0;
@@ -392,15 +400,16 @@
   const tran_low_t *nq_dequant_val = txb_info->nq_dequant_vals[coeff_idx != 0];
 #endif  // CONFIG_AOM_QM
 #endif  // CONFIG_NEW_QUANT
-  txb_info->dqcoeff[coeff_idx] = qcoeff_to_dqcoeff(qc,
+  txb_info->dqcoeff[coeff_idx] =
+      qcoeff_to_dqcoeff(qc, coeff_idx,
 #if CONFIG_NEW_QUANT
 #if CONFIG_AOM_QM
-                                                   dq_idx, coeff_idx != 0,
+                        dq_idx,
 #else
-                                                   nq_dequant_val,
+                        nq_dequant_val,
 #endif  // CONFIG_AOM_QM
 #endif  // CONFIG_NEW_QUANT
-                                                   dqv, txb_info->shift);
+                        dqv, txb_info->shift, txb_info->iqmatrix);
 }
 
 static INLINE void av1_txb_init_levels(const tran_low_t *const coeff,
@@ -2065,7 +2074,15 @@
       2;
   uint8_t levels_buf[TX_PAD_2D];
   uint8_t *const levels = set_levels(levels_buf, width);
-
+#if CONFIG_AOM_QM
+  const TX_SIZE qm_tx_size = av1_get_adjusted_tx_size(tx_size);
+  const qm_val_t *iqmatrix =
+      IS_2D_TRANSFORM(tx_type)
+          ? pd->seg_iqmatrix[mbmi->segment_id][qm_tx_size]
+          : cm->giqmatrix[NUM_QM_LEVELS - 1][0][qm_tx_size];
+#else
+  const qm_val_t *iqmatrix = NULL;
+#endif
   assert(width == (1 << bwl));
   TxbInfo txb_info = {
     qcoeff,
@@ -2092,7 +2109,8 @@
     scan_order,
     txb_ctx,
     rdmult,
-    &cm->coeff_ctx_table
+    &cm->coeff_ctx_table,
+    iqmatrix,
   };
 
   // Hash based trellis (hbt) speed feature: avoid expensive optimize_txb calls
diff --git a/av1/encoder/encodetxb.h b/av1/encoder/encodetxb.h
index 714b16c..ec4d04f 100644
--- a/av1/encoder/encodetxb.h
+++ b/av1/encoder/encodetxb.h
@@ -49,6 +49,7 @@
   TXB_CTX *txb_ctx;
   int64_t rdmult;
   const LV_MAP_CTX_TABLE *coeff_ctx_table;
+  const qm_val_t *iqmatrix;
 } TxbInfo;
 
 typedef struct TxbCache {