From 8682a9bedc4ce28bb46e9e22a2598d694cf7b88b Mon Sep 17 00:00:00 2001
From: Linty <lintydev@gmail.com>
Date: Fri, 19 Sep 2025 18:42:08 +0200
Subject: [PATCH] issue #2411 cap JPEG quality at 75 for 3XL/4XL derivatives

---
 i.php | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/i.php b/i.php
index cd80e5652..1cf683aed 100644
--- a/i.php
+++ b/i.php
@@ -598,7 +598,14 @@ if ($d_size[0]*$d_size[1] < $conf['derivatives_strip_metadata_threshold'])
   $image->strip();
 }
 
-$image->set_compression_quality( ImageStdParams::$quality );
+$compression_quality = ImageStdParams::$quality;
+
+// for big sizing never go beyond 75 quality
+if (in_array($page['derivative_type'], [IMG_4XLARGE, IMG_3XLARGE]))
+{
+  $compression_quality = min(ImageStdParams::$quality, 75);
+}
+
 $image->write( $page['derivative_path'] );
 $image->destroy();
 @chmod($page['derivative_path'], 0644);
@@ -618,5 +625,6 @@ if ($logger->severity() >= Logger::DEBUG)
     'd_size' => $d_size[0] . ' ' . $d_size[1] . ' ' . ($d_size[0]*$d_size[1]),
     'mem_usage' => function_exists('memory_get_peak_usage') ? round( memory_get_peak_usage()/(1024*1024), 1) : '',
     'timing' => $timing,
+    'quality' => $compression_quality,
     ));
 }