diff --git a/av1/av1_dx_iface.c b/av1/av1_dx_iface.c
index 0c14a97..ac8d123 100644
--- a/av1/av1_dx_iface.c
+++ b/av1/av1_dx_iface.c
@@ -557,7 +557,7 @@
           (FrameWorkerData *)worker->data1;
       struct AV1Decoder *pbi = frame_worker_data->pbi;
       for (size_t j = 0; j < pbi->num_output_frames; j++) {
-        decrease_ref_count((int)pbi->output_frame_index[j], frame_bufs, pool);
+        decrease_ref_count(pbi->output_frame_index[j], frame_bufs, pool);
       }
       pbi->num_output_frames = 0;
     }
diff --git a/av1/decoder/decoder.c b/av1/decoder/decoder.c
index c0b55b6..b38d97b 100644
--- a/av1/decoder/decoder.c
+++ b/av1/decoder/decoder.c
@@ -418,7 +418,7 @@
         // Replace any existing output frame
         assert(pbi->num_output_frames == 0 || pbi->num_output_frames == 1);
         if (pbi->num_output_frames > 0) {
-          decrease_ref_count((int)pbi->output_frame_index[0], frame_bufs, pool);
+          decrease_ref_count(pbi->output_frame_index[0], frame_bufs, pool);
         }
         pbi->output_frames[0] = cur_frame;
         pbi->output_frame_index[0] = cm->new_fb_idx;
diff --git a/av1/decoder/decoder.h b/av1/decoder/decoder.h
index cc34bbe..683a094 100644
--- a/av1/decoder/decoder.h
+++ b/av1/decoder/decoder.h
@@ -195,7 +195,7 @@
   // application calls aom_codec_decode().
   int output_all_layers;
   YV12_BUFFER_CONFIG *output_frames[MAX_NUM_SPATIAL_LAYERS];
-  size_t output_frame_index[MAX_NUM_SPATIAL_LAYERS];  // Buffer pool indices
+  int output_frame_index[MAX_NUM_SPATIAL_LAYERS];  // Buffer pool indices
   size_t num_output_frames;  // How many frames are queued up so far?
 
   // In order to properly support random-access decoding, we need