lavc/hevcdec: Fix the parsing for use_integer_mv_flag

According to 7.3.6.1, use_integer_mv_flag should be parsed if
motion_vector_resolution_control_idc equals to 2. If not present, it
equals to motion_vector_resolution_control_idc.

Signed-off-by: Linjie Fu <linjie.justin.fu@gmail.com>
Signed-off-by: Fei Wang <fei.w.wang@intel.com>

libavcodec/hevcdec.c

@@ -839,6 +839,14 @@ static int hls_slice_header(HEVCContext *s)
                        sh->max_num_merge_cand);
                 return AVERROR_INVALIDDATA;
             }
+
+            // Syntax in 7.3.6.1
+            if (s->ps.sps->motion_vector_resolution_control_idc == 2)
+                sh->use_integer_mv_flag = get_bits1(gb);
+            else
+                // Inferred to be equal to motion_vector_resolution_control_idc if not present
+                sh->use_integer_mv_flag = s->ps.sps->motion_vector_resolution_control_idc;
+
         }
 
         sh->slice_qp_delta = get_se_golomb(gb);

libavcodec/hevcdec.h

@@ -305,6 +305,7 @@ typedef struct SliceHeader {
     int tc_offset;      ///< tc_offset_div2 * 2
 
     unsigned int max_num_merge_cand; ///< 5 - 5_minus_max_num_merge_cand
+    uint8_t use_integer_mv_flag;
 
     unsigned *entry_point_offset;
     int * offset;