ffmpeg online logging : FFmpeg

Dear forum,

I am trying to acquire process information at the frame level. I am encoding from a batch of still images, so my goal is to give a frame to ffmpeg , and then check the progress information to see if it is done encoding the frame or not.

I could get this information offline using -vstats_file or -vstats and the file that is created looks like this:

frame=     1 q= 1.0 f_size=  34754 s_size=       34kB time= 0.040 br=  6950.8kbits/s avg_br=  6950.8kbits/s type= I

frame=     2 q= 1.0 f_size=   6775 s_size=       41kB time= 0.080 br=  1355.0kbits/s avg_br=  4152.9kbits/s type= P

frame=     3 q= 1.0 f_size=   5974 s_size=       46kB time= 0.120 br=  1194.8kbits/s avg_br=  3166.9kbits/s type= P

frame=     4 q= 1.0 f_size=   7406 s_size=       54kB time= 0.160 br=  1481.2kbits/s avg_br=  2745.4kbits/s type= P

frame=     5 q= 1.0 f_size=   5955 s_size=       59kB time= 0.200 br=  1191.0kbits/s avg_br=  2434.6kbits/s type= P

My ffmpeg call:

ffmpeg -f image2 -r 25 -y -s vga -pix_fmt rgb24 -i RGB/im%5d.ppm -an -vcodec mpeg4 -qscale 1 rgb.mov -vstats_file log.txt

How do I get this information in real time, i.e. every time a frame is processed ? I tried to read from the file, but ffmpeg seems to be writing chunks.

I hope someone can help me ! Best regards,

Laurent