- Fake Video Capture * or * FSR Video Capture *
fidcap
is designed to work with the FSR172X
ISP
/CCDC
raw data acquisition module for OMAP3530
.
The FSR
, or Fidcap Stream Recorder connects to a raw data acquisition unit which streams data
uses all 12-bits available on the CCDC interface. It can be thought of as a RAW12 movie camera.
The fsr172x
kernel module is not complete, hence fidcap
mmap
s some registers to set them directly.
The RAW12 data is mostly captured (about 99.4% of it) and written out to fsr.raw12
.
./fidcap
analyze ./fsr.raw12
rm ./fsr.raw12 # because fidcap appends forever
To make the system freezes more apparent and consistent you can log to memory or stop logging:
To log to memory:
ln -sf /dev/shm/fsr.raw12 ./fsr.raw12
# remember to `rm /dev/shm/fsr.raw12` after each run
To turn off logging:
ln -sf /dev/null ./fsr.raw12
During data acquisition the rest of the system is entirely unusable.
Notice that a simple loop in another process which should take 100ms takes 1 second each time capture is happening.
make
./loop-100ms
fsr_buffer_get
calls fsr_dqbuf
which calls ioctl(fsr_fd, VIDIOC_DQBUF, &v4l2_buf)
which does magic in the driver
which causes the system to freeze for the duration of the capture