fix image corruption when with multi-threaded decoding.
dequant-tables were not correctly reinitialized in the slave
contexts when a PPS came with updated matrices.
Patch by Andreas Öman %andreas A olebyn P nu%
Original thread:
date: Sep 16, 2007 6:14 AM
subject: [FFmpeg-devel] Parallelized h264 image corruption bug

Originally committed as revision 10505 to svn://svn.ffmpeg.org/ffmpeg/trunk
