From c4b9c582705079e8ae8cf4a716ae75575e55e939 Mon Sep 17 00:00:00 2001
From: Klaus Schmidinger <vdr@tvdr.de>
Date: Sat, 26 Apr 2003 15:11:17 +0200
Subject: [PATCH] Now setting the 'broken link' flag for GOPs at the beginning
 of a new video sequence

---
 CONTRIBUTORS |  2 ++
 HISTORY      |  2 ++
 cutter.c     |  9 ++++++++-
 remux.c      | 18 +++++++++++++++++-
 remux.h      |  3 ++-
 5 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index c7939fc3..196bf0cd 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -169,6 +169,8 @@ Stefan Huelswitt <huels@iname.com>
  for adapting VDR to 'libdtv' version 0.0.5
  for reporting a bug in handling of Ca parameters with values <= MAXDEVICES, which
  don't indicate an actual encrypted channel
+ for implementing setting the "broken link" flag for GOPs at the beginning of a new
+ video sequence, which avoids artefacts when cutting
 
 Ulrich Röder <roeder@efr-net.de>
  for pointing out that there are channels that have a symbol rate higher than
diff --git a/HISTORY b/HISTORY
index d5a6c198..05b0de13 100644
--- a/HISTORY
+++ b/HISTORY
@@ -2067,3 +2067,5 @@ Video Disk Recorder Revision History
   dated 2003-04-27 or higher (setting the PCR PID didn't work in earlier versions).
 - Fixed deleting the last recording in the "Recordings" menu, which started pausing
   live video (thanks to Christoph Friederich for reporting this one).
+- Now setting the "broken link" flag for GOPs at the beginning of a new video
+  sequence, which avoids artefacts when cutting (thanks to Stefan Huelswitt).
diff --git a/cutter.c b/cutter.c
index 234201cd..5ce0a2c4 100644
--- a/cutter.c
+++ b/cutter.c
@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: cutter.c 1.2 2002/08/11 11:09:23 kls Exp $
+ * $Id: cutter.c 1.3 2003/04/26 15:11:17 kls Exp $
  */
 
 #include "cutter.h"
@@ -77,6 +77,7 @@ void cCuttingThread::Action(void)
      toMarks.Add(0);
      toMarks.Save();
      uchar buffer[MAXFRAMESIZE];
+     bool cutIn = true;
      while (active) {
            uchar FileNumber;
            int FileOffset, Length;
@@ -126,6 +127,11 @@ void cCuttingThread::Action(void)
                  FileSize = 0;
                  }
               LastIFrame = 0;
+
+              if (cutIn) {
+                 cRemux::SetBrokenLink(buffer, Length);
+                 cutIn = false;
+                 }
               }
            if (safe_write(toFile, buffer, Length) < 0) {
               error = "safe_write";
@@ -151,6 +157,7 @@ void cCuttingThread::Action(void)
                  Index = Mark->position;
                  Mark = fromMarks.Next(Mark);
                  CurrentFileNumber = 0; // triggers SetOffset before reading next frame
+                 cutIn = true;
                  if (Setup.SplitEditedFiles) {
                     toFile = toFileName->NextFile();
                     if (toFile < 0) {
diff --git a/remux.c b/remux.c
index 097b4a55..c2ded246 100644
--- a/remux.c
+++ b/remux.c
@@ -8,7 +8,7 @@
  * the Linux DVB driver's 'tuxplayer' example and were rewritten to suit
  * VDR's needs.
  *
- * $Id: remux.c 1.14 2003/01/24 17:22:29 kls Exp $
+ * $Id: remux.c 1.15 2003/04/26 15:07:41 kls Exp $
  */
 
 /* The calling interface of the 'cRemux::Process()' function is defined
@@ -621,6 +621,7 @@ XXX*/
                         else if (!synced) {
                            if (pt == I_FRAME) {
                               resultDelivered = i; // will drop everything before this position
+                              SetBrokenLink(resultBuffer + i, l);
                               synced = true;
                               }
                            else {
@@ -667,3 +668,18 @@ XXX*/
   return NULL; // no useful data found, wait for more
 }
 
+void cRemux::SetBrokenLink(uchar *Data, int Length)
+{
+  if (Length > 9 && Data[0] == 0 && Data[1] == 0 && Data[2] == 1 && (Data[3] & VIDEO_STREAM_S) == VIDEO_STREAM_S) {
+     for (int i = Data[8] + 9; i < Length - 7; i++) { // +9 to skip video packet header
+         if (Data[i] == 0 && Data[i + 1] == 0 && Data[i + 2] == 1 && Data[i + 3] == 0xB8) {
+            if (!(Data[i + 7] & 0x40)) // set flag only if GOP is not closed
+               Data[i + 7] |= 0x20;
+            return;
+            }
+         }
+     dsyslog("SetBrokenLink: no GOP header found in video packet");
+     }
+  else
+     dsyslog("SetBrokenLink: no video packet in frame");
+}
diff --git a/remux.h b/remux.h
index 638a3f9e..e953001d 100644
--- a/remux.h
+++ b/remux.h
@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: remux.h 1.9 2002/11/01 10:06:46 kls Exp $
+ * $Id: remux.h 1.10 2003/04/26 14:13:11 kls Exp $
  */
 
 #ifndef __REMUX_H
@@ -44,6 +44,7 @@ public:
   cRemux(int VPid, int APid1, int APid2, int DPid1, int DPid2, bool ExitOnFailure = false);
   ~cRemux();
   uchar *Process(const uchar *Data, int &Count, int &Result, uchar *PictureType = NULL);
+  static void SetBrokenLink(uchar *Data, int Length);
   };
 
 #endif // __REMUX_H