pibuf purpose is to record in memory the last (mega)bytes of an H.264 raw stream produced by raspivid.

It is very similar to tail -c (which keep the last bytes of any stream), except:

• it keeps the H.264 headers
• it ignores garbage until the next NAL

input:   hhp11111p22222p33p444444p555p6666p77
tail -c:                     XXXXXXXXXXXXXXXX
pibuf:   XX                  ....XXXXXXXXXXXX

with:

• h: headers
• p: NAL start_prefix (0x00000001)
• 1-7: NALs
• .: garbage ignored
• X: included in output

Usage

pibuf <size>

k and m size suffixes are accepted (respectively for Kb and Mb).

For instance:

raspivid … | pibuf 10m > record.h264

record.h264 can then be read by omxplayer (or vlc).