When the input duration rounds to zero in the output timebase, the
rounded EOF timestamp can equal next_pts before any frame has been
output. In that case, do not discard a buffered frame whose timestamp
matches next_pts.
Keep the selected EOF timestamp rounding, but allow this first-frame
exception to extend output by one output frame period. Preserve start_time
trimming by checking the last input frame and EOF before rounding. A frame
located at start_time remains eligible even when its duration is zero.
Document the first-frame exception and add FATE coverage for a short
single-frame input and trimming at start_time, including a frame spanning
the start and a zero-duration frame at the start.
Fixes ticket #7361.
Signed-off-by: Skanda Vyas <skandavyas20@gmail.com>
Assisted-by: Fairy
Skanda Vyas
361174e5ea