diff --git a/pack-vid b/pack-vid
index 7ca7fa8..88f6fbd 100755
--- a/pack-vid
+++ b/pack-vid
@@ -30,6 +30,7 @@ $options = [
     'size' => $maxBytes,
     'quality' => 1.0,
     'bitrate' => 0,
+    'hdr-input' => false,
     'hdr' => false,
     'dither' => false,
     'width' => false,
@@ -71,7 +72,8 @@ if ( count ( $args ) < 2 ) {
         "  --bitrate=n      target bitrate (exclusive with --size)\n" .
         "  --size=n         target file size in bytes (exclusive with --bitrate)\n" .
         "  --quality=n      fraction of base bitrate to break on (deafult 1.0)\n" .
-        "  --hdr            force HDR input processing on\n" .
+        "  --hdr-input      force HDR input processing on\n" .
+        "  --hdr            force HDR output on (normally SDR output)\n" .
         "  --dither         enable dithering in 8-bit downconversion\n" .
         "  --width=n        override frame width in pixels\n" .
         "  --height=n       override frame height in pixels\n" .
@@ -190,9 +192,10 @@ function convert( $src, $dest, $options ) {
         $cropLeft = intval( $options['crop-left'] );
     }
     // @fixme some files are missing this? trims from qt?
-    //$hdr = $track->color_primaries === 'bt2020' || $options['hdr'];
+    //$hdrInput = $track->color_primaries === 'bt2020' || $options['hdr-input'];
     // pix_fmt: "yuv420p10le"
-    $hdr = substr( $track->pix_fmt, -5 ) === 'p10le' || $options['hdr'];
+    $hdrInput = substr( $track->pix_fmt, -5 ) === 'p10le' || $options['hdr-input'];
+    $hdr = $hdrInput && $options['hdr'];
     if ( $options['keyframe-int'] ) {
         $keyframeInt = intval( $options['keyframe-int'] );
     } else {
@@ -335,8 +338,11 @@ function convert( $src, $dest, $options ) {
         if ( $vibrance ) {
             $filters[] = "vibrance=$vibrance";
         }
+    } elseif ( $hdrInput ) {
+        $filters[] = "format=yuv420p10le";
+    } else {
+        $filters[] = "format=yuv420p";
     }
-    $filters[] = "format=yuv420p";
     if ( $crop ) {
         $filters[] = "crop=w=$frameWidth:h=$frameHeight";
     } elseif ( $letterbox ) {