ffmpeg's subtitle decoder internally converts the packet pts to
AV_TIME_BASE units based on AVCodecContext.pkt_timebase. If
pkt_timebase is not set, the PGS subtitle decoder only returns
AV_NOPTS_VALUE for timestamps. So setting pkt_timebase in decpgssub.c
fixes PGS subtitle decoding.
Confusingly, the subtitle decoder does not convert the pts *back* to the
input timebase, but instead leaves them in AV_TIME_BASE units upon
returning a decoded subtitle.
To get a head start on fixing any other such issues that might arrise, I
have also set pkt_timebase in all other avcodec decoders.
projects / handbrake / commit