release pooled memory while extracting frames

Pocket Poster/Controllers/VideoHandler.swift

@@ -140,6 +140,7 @@ class VideoHandler {
 
             while let sampleBuffer = readerOutput.copyNextSampleBuffer(),
                   let imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer) {
+                try? autoreleasepool {
                     let name = "\(frameCount).jpg"
                     let filePathName = "assets/\(name)"
                     UIApplication.shared.change(title: NSLocalizedString("Generating Video...", comment: ""), body: String(format: NSLocalizedString("Creating %@...", comment: "the message for the current image that is being generated"), filePathName))
@@ -154,6 +155,7 @@ class VideoHandler {
                         }
                     }
                 }
+            }
 
         } catch {
             print("Error reading asset: \(error)")