Possible bugs with (clip ...) #64
Description
I'm getting some confusing behavior with (clip ...) -- both when I (preview ...) and when I (render ...).
Here, I expected the previewer to show me a 1-second clip that starts at the 10-second mark of my original clip and ends at the 11-second mark of the original.
#lang racket
(require video/base video/player video/render)
(define m (clip "original.mp4"
#:start 10
#:length 1))
(preview m)
Instead, it shows me a 1-second clip starting at the 0-second mark of my original.
The behavior with (render ...) is different, but also unexpected. Again, I expected the previewer to show me a 1-second clip that starts at the 10-second mark of my original clip and ends at the 11-second mark of the original.
#lang racket
(require video/base video/player video/render)
(define m (clip "original.mp4"
#:start 10
#:length 1))
(render m "out.mp4" #:width 640 #:height 480)
Instead, I get a 10 second clip that actually does start at the right spot (the 10-second mark), and it has the 1-second of footage. But it seems to be padded at the end, making the clip 10-seconds long.
> ffmpeg -i out.mp4 2>&1 | grep "Duration"
Duration: 00:00:10.96, start: 0.000000, bitrate: 25 kb/s
I should mention that I'm on the #stable branch. I'm about to retry with the most recent version.