diff --git a/pack-vid b/pack-vid
index 78878e9..6d7a6a7 100755
--- a/pack-vid
+++ b/pack-vid
@@ -13,7 +13,7 @@ $args = $_SERVER['argv'];
 $self = array_shift( $args );
 
 $maxBytes = 4000 * 1000; // fit in 4MB
-$maxBytes = $maxBytes * 7 / 8; // leave some headroom
+$maxBytes = $maxBytes * 15 / 16; // leave some headroom
 
 $options = [
     'letterbox' => false,
@@ -148,7 +148,7 @@ function convert( $src, $dest, $options ) {
     }
 
     $mbits = 1000 * 1000;
-    if ( $bitrate < $mbits || $height < 480 ) {
+    if ( $bitrate < 1 * $mbits || $height < 480 ) {
         $frameWidth = 640;
         $frameHeight = 360;
     } elseif ( $bitrate < 2 * $mbits || $height < 720) {