diff --git a/libavcodec/exr.c b/libavcodec/exr.c
index 87e971d19c..77c0b24f39 100644
--- a/libavcodec/exr.c
+++ b/libavcodec/exr.c
@@ -1485,7 +1485,8 @@ static int decode_block(AVCodecContext *avctx, void *tdata,
                 }
 
                 // Zero out the end if xmax+1 is not w
-                memset(ptr_x, 0, axmax);
+                if (s->desc->flags & AV_PIX_FMT_FLAG_PLANAR || !c)
+                    memset(ptr_x, 0, axmax);
                 channel_buffer[c] += td->channel_line_size;
             }
         }