Hack timestamps to make them accurate

Signed-off-by: Ethan Dye <[email protected]>
ecdye · Oct 3, 2024 · 6f0db74 · 6f0db74
1 parent 757e00a
commit 6f0db74
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Showing 4 changed files with 11 additions and 27 deletions.
diff --git a/Sources/macSubtitleOCR/Subtitles/Subtitle.swift b/Sources/macSubtitleOCR/Subtitles/Subtitle.swift
@@ -17,8 +17,6 @@ class Subtitle {
     var imageYOffset: Int?
     var imageWidth: Int?
     var imageHeight: Int?
-    var imageEvenOffset: Int?
-    var imageOddOffset: Int?
     var imageData: Data?
     var imagePalette: [UInt8]?
     var imageAlpha: [UInt8]?

diff --git a/Sources/macSubtitleOCR/Subtitles/VobSub/VobSub.swift b/Sources/macSubtitleOCR/Subtitles/VobSub/VobSub.swift
@@ -47,26 +47,16 @@ class VobSub {
         }
     }
 
-    func parseIdxFile(idxData: String) -> [IdxSubtitleReference] {
+    func parseIdxFile(idxData: String) throws -> [IdxSubtitleReference] {
         var subtitles = [IdxSubtitleReference]()
         let lines = idxData.split(separator: "\n")
-        let timestampRegex: NSRegularExpression
-        let offsetRegex: NSRegularExpression
-        let dateFormatter = DateFormatter()
-        dateFormatter.dateFormat = "HH:mm:ss:SSS"
-        do {
-            timestampRegex = try NSRegularExpression(pattern: "timestamp: (\\d{2}:\\d{2}:\\d{2}:\\d{3})")
-            offsetRegex = try NSRegularExpression(pattern: "filepos: (\\w+)")
-        } catch {
-            print("Error: Failed to create regular expressions: \(error)", to: &stderr)
-            return []
-        }
+        let timestampRegex = try NSRegularExpression(pattern: "timestamp: (\\d{2}:\\d{2}:\\d{2}:\\d{3})")
+        let offsetRegex = try NSRegularExpression(pattern: "filepos: (\\w+)")
 
         for line in lines {
             if line.starts(with: "palette:") {
                 let entries = line.split(separator: ", ").map { String($0) }
                 for entry in entries {
-                    print(entry.hexToBytes)
                     idxPalette.append(contentsOf: entry.hexToBytes)
                 }
             }
@@ -133,7 +123,7 @@ class VobSub {
             print("Error: Failed to read files", to: &stderr)
             return
         }
-        let subtitles = parseIdxFile(idxData: idxData)
+        let subtitles = try parseIdxFile(idxData: idxData)
         try extractSubtitleImages(subFile: subFile, idxReference: subtitles)
     }
 }
diff --git a/Sources/macSubtitleOCR/Subtitles/VobSub/VobSubError.swift b/Sources/macSubtitleOCR/Subtitles/VobSub/VobSubError.swift
diff --git a/Sources/macSubtitleOCR/Subtitles/VobSub/VobSubParser.swift b/Sources/macSubtitleOCR/Subtitles/VobSub/VobSubParser.swift
@@ -116,6 +116,10 @@ func readSubFrame(pic: inout Subtitle, subFile: FileHandle, offset: UInt64, next
     index += 2
 
     var alphaSum = 0
+    let relativeEndTimestamp = controlHeader.value(ofType: UInt16.self, at: endOfControl - 1)! << 10
+    let endTimestamp = pic.startTimestamp! + TimeInterval(relativeEndTimestamp) / 90.0 - 9 // Not sure why we need to subtract 9 but its pretty close to accurate
+    pic.endTimestamp = endTimestamp
+    logger.debug("Display delay is \(endTimestamp)")
     while index < endOfControl {
         let command = controlHeader[index]
         index += 1
@@ -125,6 +129,9 @@ func readSubFrame(pic: inout Subtitle, subFile: FileHandle, offset: UInt64, next
             break // Set subtitle as forced
         case 1:
             break // Start display
+        case 2:
+            let displayDelay = controlHeader.value(ofType: UInt16.self, at: 0)
+            logger.debug("Display delay is \(displayDelay!)")
         case 3:
             var byte = controlHeader[index]
             index += 1