From f9b12cc0918e1d16764f15809b8dd83fc79b82a3 Mon Sep 17 00:00:00 2001
From: "Y.Tory" <5343692+kagemomiji@users.noreply.github.com>
Date: Mon, 24 Jun 2024 12:35:28 +0000
Subject: [PATCH] kagemomiji/airsonic-advanced#512 Changed algorithm for
 risizing non square cover art

---
 .../player/controller/CoverArtController.java | 20 +++++++++-----
 .../player/service/CoverArtCreateService.java |  2 +-
 .../org/airsonic/player/util/ImageUtil.java   | 26 +++++++++++++++++++
 3 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/airsonic-main/src/main/java/org/airsonic/player/controller/CoverArtController.java b/airsonic-main/src/main/java/org/airsonic/player/controller/CoverArtController.java
index a8aea6634..5edf57b4a 100644
--- a/airsonic-main/src/main/java/org/airsonic/player/controller/CoverArtController.java
+++ b/airsonic-main/src/main/java/org/airsonic/player/controller/CoverArtController.java
@@ -62,7 +62,7 @@
  * @author Sindre Mehus
  */
 @Controller
-@RequestMapping({"/coverArt", "/ext/coverArt", "/coverArt.view", "/ext/coverArt.view"})
+@RequestMapping({ "/coverArt", "/ext/coverArt", "/coverArt.view", "/ext/coverArt.view" })
 public class CoverArtController {
 
     public static final String ALBUM_COVERART_PREFIX = "al-";
@@ -70,13 +70,20 @@ public class CoverArtController {
     public static final String PLAYLIST_COVERART_PREFIX = "pl-";
     public static final String PODCAST_COVERART_PREFIX = "pod-";
 
+    // Version of the cover art generation algorithm.
+    // Increment this if the algorithm changes.
+    private static final int COVERART_VERSION = 1;
+
     static final Logger LOG = LoggerFactory.getLogger(CoverArtController.class);
 
-    @Autowired MediaFileService mediaFileService;
-    @Autowired CoverArtService coverArtService;
+    @Autowired
+    MediaFileService mediaFileService;
+    @Autowired
+    CoverArtService coverArtService;
     @Autowired
     private SettingsService settingsService;
-    @Autowired PlaylistService playlistService;
+    @Autowired
+    PlaylistService playlistService;
     @Autowired
     private CoverArtCreateService coverArtCreateService;
     @Autowired
@@ -93,7 +100,8 @@ public void init() {
      * get last modified time epoch millisecond
      *
      * @param coverArtRequest target coverArtRequest
-     * @return last modified time in epoch milliseconds. if coverArtRequest id null, then return -1L
+     * @return last modified time in epoch milliseconds. if coverArtRequest id null,
+     *         then return -1L
      */
     /*
     private long getLastModifiedMiili(CoverArtRequest coverArtRequest) {
@@ -198,7 +206,7 @@ private void sendUnscaled(CoverArtRequest coverArtRequest, HttpServletResponse r
     }
 
     private Path getCachedImage(CoverArtRequest request, int size) throws IOException {
-        String hash = DigestUtils.md5Hex(request.getKey());
+        String hash = DigestUtils.md5Hex(request.getKey() + "-" + COVERART_VERSION);
         String encoding = request.getCoverArt() != null ? "jpeg" : "png";
         Path cachedImage = getImageCacheDirectory(size).resolve(hash + "." + encoding);
 
diff --git a/airsonic-main/src/main/java/org/airsonic/player/service/CoverArtCreateService.java b/airsonic-main/src/main/java/org/airsonic/player/service/CoverArtCreateService.java
index 9c9167efd..5875bc72b 100644
--- a/airsonic-main/src/main/java/org/airsonic/player/service/CoverArtCreateService.java
+++ b/airsonic-main/src/main/java/org/airsonic/player/service/CoverArtCreateService.java
@@ -228,7 +228,7 @@ public BufferedImage createImage(CoverArtRequest coverArtRequest, int size) {
                     if (bimg == null) {
                         reason = "ImageIO.read";
                     } else {
-                        return ImageUtil.scale(bimg, size, size);
+                        return ImageUtil.scaleToSquare(bimg, size);
                     }
                 }
                 LOG.warn("Failed to process cover art {}: {} failed", coverArt, reason);
diff --git a/airsonic-main/src/main/java/org/airsonic/player/util/ImageUtil.java b/airsonic-main/src/main/java/org/airsonic/player/util/ImageUtil.java
index bb120a3ba..0e9bf174d 100644
--- a/airsonic-main/src/main/java/org/airsonic/player/util/ImageUtil.java
+++ b/airsonic-main/src/main/java/org/airsonic/player/util/ImageUtil.java
@@ -66,4 +66,30 @@ public static BufferedImage scale(BufferedImage image, int width, int height) {
         return thumb;
     }
 
+    public static BufferedImage scaleToSquare(BufferedImage image, int size) {
+        int w = image.getWidth();
+        int h = image.getHeight();
+        int scale = Math.max(w, h);
+
+        BufferedImage squareImage = new BufferedImage(scale, scale, BufferedImage.TYPE_INT_RGB);
+        squareImage.getGraphics().drawImage(image, (scale - w) / 2, (scale - h) / 2, null);
+
+        do {
+            scale /= 2;
+            if (scale < size) {
+                scale = size;
+            }
+            BufferedImage temp = new BufferedImage(scale, scale, BufferedImage.TYPE_INT_RGB);
+            Graphics2D g2 = temp.createGraphics();
+            g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
+                    RenderingHints.VALUE_INTERPOLATION_BILINEAR);
+            g2.drawImage(squareImage, 0, 0, temp.getWidth(), temp.getHeight(), null);
+            g2.dispose();
+
+            squareImage = temp;
+        } while (scale != size);
+
+        return squareImage;
+    }
+
 }