1 files changed, 4 insertions, 1 deletions
diff --git a/src/bitstream.c b/src/bitstream.c
index 71a3d75..dc8109b 100644
--- a/src/bitstream.c
+++ b/src/bitstream.c
@@ -257,7 +257,10 @@ h_rewindNbits (huffdec_bitbuf * bb, guint N)
     bb->buf_bit_idx = 0;
     bits = 8 - (N % 8);
     bytes = (N + 8 + BS_ACUM_SIZE) >> 3;
-    bb->buf_byte_idx -= bytes;
+    if (bb->buf_byte_idx >= bytes)
+      bb->buf_byte_idx -= bytes;
+    else 
+      bb->buf_byte_idx = 0;
     bb->remaining += bytes;
     h_getbits (bb, bits);
   }