diff --git a/src/immichclient.cpp b/src/immichclient.cpp
index c2fac3f..6974c1d 100644
--- a/src/immichclient.cpp
+++ b/src/immichclient.cpp
@@ -5,6 +5,8 @@
 #include <QEventLoop>
 #include <QFile>
 #include <QFileInfo>
+#include <QBuffer>
+#include <QImageReader>
 #include <QJsonArray>
 #include <QJsonDocument>
 #include <QJsonObject>
@@ -17,6 +19,20 @@
 namespace {
 const int kMetadataTimeoutMs = 15000;
 const int kAssetTimeoutMs = 30000;
+QString DetectImageExtension(const QByteArray &data)
+{
+  QBuffer buffer;
+  buffer.setData(data);
+  if (!buffer.open(QIODevice::ReadOnly))
+    return "";
+  QImageReader reader(&buffer);
+  if (!reader.canRead())
+    return "";
+  QByteArray fmt = reader.format().toLower();
+  if (fmt == "jpeg")
+    fmt = "jpg";
+  return QString::fromUtf8(fmt);
+}
 }
 
 ImmichClient::ImmichClient(const ImmichConfig &configIn)
@@ -356,6 +372,11 @@ QString ImmichAssetCache::findExisting(const QString &assetId) const
   QStringList matches = dir.entryList(QStringList() << (assetId + "_*"), QDir::Files, QDir::Time);
   if (matches.isEmpty())
     return "";
+  for (const auto &match : matches)
+  {
+    if (match.endsWith(".skip"))
+      return dir.filePath(match);
+  }
   return dir.filePath(matches.first());
 }
 
@@ -418,8 +439,35 @@ QString ImmichAssetCache::getCachedPath(const QString &assetId, const QString &a
   QString existing = findExisting(assetId);
   if (!existing.isEmpty())
   {
-    Log("Immich cache hit: ", assetId.toStdString());
-    return existing;
+    if (existing.endsWith(".skip"))
+    {
+      Log("Immich skip marker: ", assetId.toStdString());
+      return "";
+    }
+    QFileInfo info(existing);
+    if (info.size() <= 0)
+    {
+      QFile::remove(existing);
+    }
+    else if (existing.endsWith(".img"))
+    {
+      QImageReader reader(existing);
+      if (!reader.canRead())
+      {
+        Log("Immich cache invalid: ", existing.toStdString());
+        QFile::remove(existing);
+      }
+      else
+      {
+        Log("Immich cache hit: ", assetId.toStdString());
+        return existing;
+      }
+    }
+    else
+    {
+      Log("Immich cache hit: ", assetId.toStdString());
+      return existing;
+    }
   }
 
   QByteArray data;
@@ -427,8 +475,31 @@ QString ImmichAssetCache::getCachedPath(const QString &assetId, const QString &a
   if (!client.downloadAsset(assetId, data, contentType))
     return "";
 
+  QString detectedExt = DetectImageExtension(data);
+  if (detectedExt.isEmpty())
+  {
+    Log("Immich download not an image for asset: ", assetId.toStdString());
+    QString skipName = assetId + "_unsupported.skip";
+    QDir dir(cacheDirPath);
+    QFile skipFile(dir.filePath(skipName));
+    if (skipFile.open(QIODevice::WriteOnly))
+    {
+      skipFile.write("unsupported");
+      skipFile.close();
+    }
+    return "";
+  }
+
   QString safeName = sanitizeFileName(assetName);
-  QString extension = extensionForContentType(contentType);
+  QString extension = detectedExt;
+  if (extension.isEmpty())
+    extension = extensionForContentType(contentType);
+  if (extension == "img")
+  {
+    QString suffix = QFileInfo(assetName).suffix().toLower();
+    if (!suffix.isEmpty())
+      extension = suffix;
+  }
   QString filename = assetId + "_" + safeName + "." + extension;
 
   QDir dir(cacheDirPath);