diff --git a/libavformat/pnm.c b/libavformat/pnm.c
index a831e212d2b5fe5eaf724f151864a150c5ab39ce..fb4d3d2ad36ab40c01cbd2dc416d6d303a92b7e1 100644
--- a/libavformat/pnm.c
+++ b/libavformat/pnm.c
@@ -394,7 +394,7 @@ static int pnm_probe(AVProbeData *pd)
     if (pd->buf_size >= 8 &&
         p[0] == 'P' &&
         p[1] >= '4' && p[1] <= '6' &&
-        p[2] == '\n')
+        pnm_space(p[2]) )
         return AVPROBE_SCORE_MAX - 1; /* to permit pgmyuv probe */
     else
         return 0;