SRT Subtitle has 1 frame offset with XDCAM422i50

[Rens Dijkshoorn]

Hi,

when using the command below the first subtitle is dropped, we start
on the
first frame with 00:00:00:01 with xcdam422i50.MXF as input format.

While tests with IMX50i50.MXF and DVCP...@1080i50.MXF are spot on

Command:

ffmbc -i xdca...@i50.MXF \
-vf sub=file=sub.srt:vmargin=1000:box=1:boxcolor=0x00000080 \
-aspect 16:9 -vcodec libx264 -faststart 1 -profile baseline -b 1500k -
g 25 \
-map_audio_channel 0:1:0:0:1 -map_audio_channel 0:2:0:0:1 \
-ac 2 -acodec libfaac -ab 128k file_sub.mp4

The SRT file is used to provide TC display

SRT file sub.srt

0
00:00:00,000 --> 00:00:00,001
00:00:00:00

1
00:00:00,040 --> 00:00:00,041
00:00:00:01

2
00:00:00,080 --> 00:00:00,081
00:00:00:02

etc...

any idea

Regards

Rens Dijkshoorn