overleaf-cep/server-ce/hotfix/6.1.2/issue_31527.patch

--- services/filestore/app/js/FileConverter.js
+++ services/filestore/app/js/FileConverter.js
@@ -22,49 +22,44 @@ export default {
 }
 
 async function convert(sourcePath, requestedFormat) {
-  const width = '600x'
+  const width = 1500
   return await _convert(sourcePath, requestedFormat, [
-    'convert',
-    '-define',
-    `pdf:fit-page=${width}`,
-    '-flatten',
-    '-density',
-    '300',
-    `${sourcePath}[0]`,
+    'pdftocairo',
+    '-png',
+    '-singlefile',
+    '-scale-to-x',
+    width.toString(),
+    '-scale-to-y',
+    '-1',
+    sourcePath,
   ])
 }
 
 async function thumbnail(sourcePath) {
-  const width = '260x'
-  return await convert(sourcePath, 'png', [
-    'convert',
-    '-flatten',
-    '-background',
-    'white',
-    '-density',
-    '300',
-    '-define',
-    `pdf:fit-page=${width}`,
-    `${sourcePath}[0]`,
-    '-resize',
-    width,
+  const width = 700
+  return await _convert(sourcePath, 'png', [
+    'pdftocairo',
+    '-png',
+    '-singlefile',
+    '-scale-to-x',
+    width.toString(),
+    '-scale-to-y',
+    '-1',
+    sourcePath,
   ])
 }
 
 async function preview(sourcePath) {
-  const width = '548x'
-  return await convert(sourcePath, 'png', [
-    'convert',
-    '-flatten',
-    '-background',
-    'white',
-    '-density',
-    '300',
-    '-define',
-    `pdf:fit-page=${width}`,
-    `${sourcePath}[0]`,
-    '-resize',
-    width,
+  const width = 1000
+  return await _convert(sourcePath, 'png', [
+    'pdftocairo',
+    '-png',
+    '-singlefile',
+    '-scale-to-x',
+    width.toString(),
+    '-scale-to-y',
+    '-1',
+    sourcePath,
   ])
 }
 
@@ -78,7 +73,8 @@ async function _convert(sourcePath, requestedFormat, command) {
   const timer = new metrics.Timer('imageConvert')
   const destPath = `${sourcePath}.${requestedFormat}`
 
-  command.push(destPath)
+  const outputBaseName = sourcePath
+  command.push(outputBaseName)
   command = Settings.commands.convertCommandPrefix.concat(command)
 
   try {