This is to accommodate output packets for both compressed
data and psnr stats. For each frame, there are at least
one packet for compressed data and one for psnr stats. For
a max lag of 25, 64 is large enough to cover all lagged
frames at the end of encoding.

Change-Id: If20787fbc86f96e1aa16a3ccf2adc93e6c1e3d5f