I'm having issues with dropped or skipped frames on 95% of my recordings.
usually every 10 or 15 sec in the recordings perhaps half a sec is missing from the recording, creating a noticeable skip. If I do 2 minute test recordings, they sometimes are only 1:48 in length (I assume this is the time lost or skipped that is reducing the output length - although I've read the timing is not 'perfect').
My workflow is record to the pi, convert to MP4 with MP4Box, then transfer to PC with WinSCP.
This is a typical command:
Code: Select all
raspivid -t 120000 -w 640 -h 360 -fps 25 -sh 70 -vf -hf -o twomin360.h264
(Writing to a USB thumb drive that holds the filesystem)
I suppose its possible the MP4Box conversion is dropping the frames.. but unlikely right?
Doing some testing tonight shows that every resolution above 640x360 is dropping frames on recording.
Originally I had the SD card holding the FS. Now I have a USB thumb drive holding the FS, but the results seem similar.
I overclocked to 950MHz earlier this evening, with no apparent improvement.
I've boosted the swap file size to 512Mb, and still no improvement. (Although the first video after doing that looked OK... seems it was a red herring!)
So.... is this what is to be expected? Am I expecting too much from the setup?
Have others had similar difficulties?
I mean its not a HUGE deal... but as I've not seen anyone discuss it before, I have just assumed skipping frames was non-existent.