esreport -framesize reports incorrect frametypes for MPEG-2

[GoogleCodeExporter]

What steps will reproduce the problem?
1. esreport -framesize movie.es (where es file is MPEG-2)

What is the expected output? What do you see instead?

Expected
Frame sizes ranged from   343 to   19687 bytes, mean   3667.11
          I frames from 19687 to   19687 bytes, mean  19687.00
          P frames from   719 to    9439 bytes, mean   3804.33
          B frames from   343 to     409 bytes, mean    380.80

Actual
Frame sizes ranged from   343 to   19687 bytes, mean   3667.11
          Forbidden frames from 19687 to   19687 bytes, mean  19687.00
          I frames from   719 to    9439 bytes, mean   3804.33
          P frames from   343 to     409 bytes, mean    380.80

What version of the product are you using? On what operating system?

52e9e332bd628dbce0ba4ec5535a12838e14f487

Please provide any additional information below.

Diff available from
http://code.google.com/r/jenniferfreeman-tstools/source/detail?r=cc922f87d3bbe31
35a4dd7c47bf200671edea79e

Original issue reported on code.google.com by [email protected] on 15 Mar 2012 at 3:44