mythbuntu-bugs team mailing list archive

[Cory Maccarrone <darkstar6262@xxxxxxxxx>]

Public bug reported:

Binary package hint: mythtv

When playing videos using MythVideo on my local hard drive, the
situation frequently occurs that mythtv will set the video scan to
"Interlaced" and lock it there, causing frame stuttering and flickering.
This is in a progressive stream.

I've managed to narrow down what's happening, and it seems whenever the
stream switches from 24000/1001 to 30000/1001 frames, myth thinks the
stream is interlaced.  Problem is, when the frame rate goes back, myth
never sets the video scan back to progressive, so I end up with
deinterlacing applied to a progressive stream.

I made a quick patch to the source code that for me fixes the problem:

--- libs/libmythtv/NuppelVideoPlayer.cpp-orig	2010-04-17 12:38:32.799073334 -0700
+++ libs/libmythtv/NuppelVideoPlayer.cpp	2010-04-17 12:38:43.867081365 -0700
@@ -989,7 +989,6 @@
             {
                 VERBOSE(VB_PLAYBACK, LOC + "Locking scan to Interlaced.");
                 SetScanType(kScan_Interlaced);
-                return;
             }
         }
         m_scan_tracker++;

However, this change was implemented in revision 22121 of mythtv in
response to this mailing list post:

http://mythtv.org/pipermail/mythtv-dev/2009-October/066439.html

So, I don't imagine this is a good fix.  Better would be to fix mythtv's
handling of frame rate changes.

For reference, this is on the latest beta release of Mythbuntu 10.04.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: libmyth-0.23-0 0.23.0+fixes24158-0ubuntu1
ProcVersionSignature: Ubuntu 2.6.32-19.28-generic 2.6.32.10+drm33.1
Uname: Linux 2.6.32-19-generic i686
NonfreeKernelModules: nvidia
Architecture: i386
Date: Sat Apr 17 12:32:34 2010
InstallationMedia: Mythbuntu 10.04 "Lucid Lynx" - Beta i386 (20100318)
Installed_mythplugins-dbg: 0.0
Installed_mythtv-dbg: 0.0
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: mythtv

** Affects: mythbuntu
     Importance: Undecided
         Status: New

** Affects: mythtv (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: apport-bug i386 lucid

-- 
MythTV incorrectly detects interlaced stream on progressive content
https://bugs.launchpad.net/bugs/565557
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Bug Team, which is subscribed to mythtv in ubuntu.

Status in Mythbuntu, Ubuntu derivative focused upon MythTV: New
Status in “mythtv” package in Ubuntu: New

Bug description:
Binary package hint: mythtv

When playing videos using MythVideo on my local hard drive, the situation frequently occurs that mythtv will set the video scan to "Interlaced" and lock it there, causing frame stuttering and flickering.  This is in a progressive stream.

I've managed to narrow down what's happening, and it seems whenever the stream switches from 24000/1001 to 30000/1001 frames, myth thinks the stream is interlaced.  Problem is, when the frame rate goes back, myth never sets the video scan back to progressive, so I end up with deinterlacing applied to a progressive stream.

I made a quick patch to the source code that for me fixes the problem:

--- libs/libmythtv/NuppelVideoPlayer.cpp-orig	2010-04-17 12:38:32.799073334 -0700
+++ libs/libmythtv/NuppelVideoPlayer.cpp	2010-04-17 12:38:43.867081365 -0700
@@ -989,7 +989,6 @@
             {
                 VERBOSE(VB_PLAYBACK, LOC + "Locking scan to Interlaced.");
                 SetScanType(kScan_Interlaced);
-                return;
             }
         }
         m_scan_tracker++;

However, this change was implemented in revision 22121 of mythtv in response to this mailing list post:

http://mythtv.org/pipermail/mythtv-dev/2009-October/066439.html

So, I don't imagine this is a good fix.  Better would be to fix mythtv's handling of frame rate changes.

For reference, this is on the latest beta release of Mythbuntu 10.04.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: libmyth-0.23-0 0.23.0+fixes24158-0ubuntu1
ProcVersionSignature: Ubuntu 2.6.32-19.28-generic 2.6.32.10+drm33.1
Uname: Linux 2.6.32-19-generic i686
NonfreeKernelModules: nvidia
Architecture: i386
Date: Sat Apr 17 12:32:34 2010
InstallationMedia: Mythbuntu 10.04 "Lucid Lynx" - Beta i386 (20100318)
Installed_mythplugins-dbg: 0.0
Installed_mythtv-dbg: 0.0
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: mythtv