package libpostproc52 4:0.8.17-0ubuntu0.12.04.2 failed to install/upgrade: libpostproc52:amd64 6

Error occurred during 12.04 -> 14.04 upgrade via do-release-upgrade.

ProblemType: Package
DistroRelease: Ubuntu 14.04
Package: libpostproc52 4:0.8.17-0ubuntu0.12.04.2
ProcVersionSignature: Ubuntu 3.2.0-104.145-generic 3.2.79
Uname: Linux 3.2.0-104-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.1-0ubuntu3.21
Architecture: amd64
Date: Mon Jun 20 12:49:13 2016
Dependencies:
 gcc-4.9-base 4.9.3-0ubuntu4
 libc6 2.19-0ubuntu6.9
 libgcc1 1:4.9.3-0ubuntu4
 multiarch-support 2.19-0ubuntu6.9
DuplicateSignature: package:libpostproc52:4:0.8.17-0ubuntu0.12.04.2:libpostproc52:amd64 6
ErrorMessage: libpostproc52:amd64 6
InstallationDate: Installed on 2012-12-03 (1294 days ago)
InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120823.1)
RelatedPackageVersions:
 dpkg 1.17.5ubuntu5.6
 apt 1.0.1ubuntu2.14
SourcePackage: libav
Title: package libpostproc52 4:0.8.17-0ubuntu0.12.04.2 failed to install/upgrade: libpostproc52:amd64 6
UpgradeStatus: Upgraded to trusty on 2016-06-20 (0 days ago)