calculations for target and maximum bitrate for a variety of small frame sizes are less than 0.19 Mbps. however, cs4 will not accept a setting lower than 0.19 Mbps in the export settings dialog box. except for frame size, all other settings are f4v default. how do i produce f4v output with a bitrate lower than 0.19 Mbps? --david
Your calculations must be wrong, unless your resolution is around 1 x 1. The alternative is to just export a black frame.
the bitrate calculation is a formula published by adobe's kush amerashinghe at
w * h * fps * mr * 0.07 = bps
width and height in pixels
fps frames per second - i'm using 15
mr is motion rank - i'm using 2
the resulting playback quality from a web site is good in six frame sizes tested so far, smallest being
192x144 and 128x72 and largest 768x432. 90-minute movies must work with a dial-up connection.
for the smaller frames, the 0.19 limit is making f4v file sizes larger than necessary.