deim31:
As Andrew said, it is there in "flags" (at least for mp4 and mov) but with the video I tried, I saw no difference. Steps to get flag "bitexact":
1) bring up render menu and set your File Format as usual to FFMPEG/mp4 or mov (have not tried others)
2) click on the Video wrench, then click on box in Video Options "view" which brings up a menu
3) in the 2nd line on the top right is the box Kind which is set to codec; use the arrow to set to "ffmpeg"
4) on the left side scroll down in the option area and look for "flags" and highlight that
5) above the option header is now the word "flags" with a down arrow; click on arrow and you see "bitexact" which you should click on and you will see the value switch from 0x0 to 0x00800000 (I lost count of zeros but you get it)
6 ) click on Apply box below the Kind box and click OK button in menu
Please let us know if this actually works.