FFmpeg Images 2 Video conversion problem ??

[lostnucleus]

I got folder full of images , number of images = 600 , I want to make a video which plays one image per second hence duration of that video gona be 600 sec i.e 10 mins . (frame rate 1per sec)

So to do this i gave

ffmpeg -i /home/user/folder/image%d.jpeg -r 1 -f avi output.avi

but ffmpeg only processed 28 images and made the output video of duration 28 sec .

and when I increased -r value to 2 it processed 56 images with output video of duration 28 sec.

somehow its making output video always of 28 sec ??
I got no clue why its doing this my ffmpeg version is 0.5 , operating system Ubuntu 9 .

Thanks in Advance.

[lostnucleus]

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