From 64d494825cb5b891f3bfb707ffac1d212c4c30c3 Mon Sep 17 00:00:00 2001
From: Brion Vibber <brion@pobox.com>
Date: Sat, 9 Sep 2023 18:14:45 -0700
Subject: [PATCH] sizes, keyframes, default exposure

---
 pack-set |  3 ++-
 pack-vid | 51 ++++++++++++++++++++++++++++++++-------------------
 2 files changed, 34 insertions(+), 20 deletions(-)

diff --git a/pack-set b/pack-set
index b9afb7d..9d22560 100755
--- a/pack-set
+++ b/pack-set
@@ -14,7 +14,8 @@ do
 
         #COMMON="$OPTS"
         #COMMON="$OPTS --exposure=-2.5 --peak=141"
-        COMMON="$OPTS --exposure=-1 --peak=500"
+        #COMMON="$OPTS --exposure=-1 --peak=500"
+        COMMON="$OPTS --peak=1000"
         SPEED_SMALL="veryslow"
         SPEED_LARGE="slow"
 
diff --git a/pack-vid b/pack-vid
index 85161ee..3c83dcc 100755
--- a/pack-vid
+++ b/pack-vid
@@ -30,6 +30,7 @@ $options = [
     'dither' => false,
     'width' => false,
     'height' => false,
+    'keyframe-int' => 0,
 ];
 
 while ( count( $args ) > 0 && substr( $args[0], 0, 2 ) == '--' ) {
@@ -47,19 +48,20 @@ if ( count ( $args ) < 2 ) {
     die(
         "Usage: $self [options...] <srcfile.mp4> <destfile.mp4>\n" .
         "Options:\n" .
-        "  --crop         crop to 16:9\n" .
-        "  --letterbox    pad to 16:9\n" .
-        "  --no-audio     strip audio\n" .
-        "  --exposure=n   adjust exposure\n" .
-        "  --peak=n       set HDR peak nits\n" .
-        "  --preset=key   set h.264 encoding preset\n" .
-        "  --fps=n        frame rate limit\n" .
-        "  --size=n       target file size in bytes (default 3.5M)\n" .
-        "  --quality=n    fraction of base bitrate to break on (deafult 0.75)\n" .
-        "  --hdr          force HDR input processing on\n" .
-        "  --dither       enable dithering in 8-bit downconversion\n" .
-        "  --width        override frame width in pixels\n" .
-        "  --height       override frame height in pixels\n"
+        "  --crop           crop to 16:9\n" .
+        "  --letterbox      pad to 16:9\n" .
+        "  --no-audio       strip audio\n" .
+        "  --exposure=n     adjust exposure\n" .
+        "  --peak=n         set HDR peak nits\n" .
+        "  --preset=key     set h.264 encoding preset\n" .
+        "  --fps=n          frame rate limit\n" .
+        "  --size=n         target file size in bytes (default 3.5M)\n" .
+        "  --quality=n      fraction of base bitrate to break on (deafult 0.75)\n" .
+        "  --hdr            force HDR input processing on\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" .
+        "  --keyframe-int=n set keyframe interval (default 0)\n"
     );
 }
 [ $src, $dest ] = $args;
@@ -151,14 +153,18 @@ function convert( $src, $dest, $options ) {
     }
     $track = $videoTracks[0];
 
-    $duration = floatval( $track->duration );
+    $duration = floatval( $probe->format->duration );
     $width = $track->width;
     $height = $track->height;
     // @fixme some files are missing this? trims from qt?
     //$hdr = $track->color_primaries === 'bt2020' || $options['hdr'];
     // pix_fmt: "yuv420p10le"
     $hdr = substr( $track->pix_fmt, -5 ) === 'p10le' || $options['hdr'];
-    $keyframeInt = ceil( $duration * 60 );
+    if ( $options['keyframe-int'] ) {
+        $keyframeInt = intval( $options['keyframe-int'] );
+    } else {
+        $keyframeInt = intval( ceil( $duration * 60 ) );
+    }
 
     $bitrate = floor( $maxBits / $duration );
 
@@ -175,7 +181,6 @@ function convert( $src, $dest, $options ) {
     }
 
     $bitrate = max( $bitrate, 16000 );
-
     $mbits = 1000 * 1000;
     $base = intval( $mbits * floatval( $options['quality'] ) );
     if ( $bitrate < 0.125 * $base || $height < 144 ) {
@@ -206,17 +211,25 @@ function convert( $src, $dest, $options ) {
         $frameWidth = 1280;
         $frameHeight = 720;
         $bitrate = min( $bitrate, $base * 4 );
-    } else {
+    } elseif ( $bitrate < 8 * $base || $height < 1440) {
         $frameWidth = 1920;
         $frameHeight = 1080;
         $bitrate = min( $bitrate, $base * 8 );
+    } elseif ( $bitrate < 16 * $base || $height < 2160) {
+        $frameWidth = 2560;
+        $frameHeight = 1440;
+        $bitrate = min( $bitrate, $base * 16 );
+    } else {
+        $frameWidth = 3840;
+        $frameHeight = 2160;
+        $bitrate = min( $bitrate, $base * 32 );
     }
 
     $aspect = $width / $height;
     $pixels = $width * $height;
 
-    // canonical base rate is 1 megabit at 480p
-    $bitrate = min( $bitrate, 4 * $base );
+    // canonical min rate is 0.125 megabit at 144p
+    $bitrate = max( $bitrate, 0.125 * $base );
 
     /*
     $minWidth = 640;