[FFmpeg-user] need help

[Abeer Awad]

hi, i need a ffmpeg command that extracts the I,P B frames as images in the folder and i want to know the GOP pattern , and how to recognize them as inages to which type they belong(I,P,or B)? can anyone help me? i tried this
ffmpeg -i video.mpg -vf "select='eq(pict_type,I)' " -acodec copy -f mp4 -y /b
but i did not get any thing in the output folder, i need the 3 types as images in the folder and i want something to discriminate between them.
 I am a bigginer in using ffmpeg and i really need u help, these files (frames as images) will be input to my project in matlab.
i have to extract the types and depending whether it is I or P or B i will continue.... pleeeeeeeeease help