[FFmpeg-user] VDR recording - dvd subtitle track not decoded

[Richard F]

Hi List

I wonder if anyone can suggest a fix for a problem with ffmpeg not
decoding the subtitle stream in VDR 1.x recordings?
ffmpeg identifies the stream type as "DVD Subtitle (spu)".
If I try to process this with ffmpeg (concat, extract or transcode),
ffmpeg reports 0 bytes in the subtitle track.
There is a warning "start time for stream 3 is not set in
estimate_timings_from_pts", unsure if that's the issue

However ProjectX can extract and show the subtitles

Link below is a small 12s sample (001.vdr) with 1 subtitle in it
(towards the end - in the commercial)

https://drive.google.com/folderview?id=0B78j3Hs03x3oQU5kaWJtaUlWNkk&usp=sharing

Also the sub file extracted by ProjectX, Project X log file listing the
steams etc. and idx file etc
+ screenshot of extracted subtitle in "subtitle edit"
+ detailed output from ffprobe

My goal is to script ffmpeg to transcode hundreds of such files with
their subtitles if possible.

Thanks