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Figure 11 Player with no stream
In simple applications, only one multicast stream will be visible. To start decoding the stream select the
stream and then double click it. Details relevant to each stream are presented in a tabular form in the
Stream List window.
7.4
AES Encrypted Streams
If the selected stream is AES encrypted by upstream hardware, then the user will be prompted for the
reciprocal AES key.
AES keys employed are 32 hexadecimal characters long (128 bits).
Once the key is entered, the main software decoder window is launched. The Options menu on the
decoder window presents the following choices:
Quarter Resolution. Selection of this option presents the decoded video at a quarter of its full
size.
Full resolution. Selection of this option presents the decoded video in at its full size. Full
resolution and quarter resolution options are mutually exclusive.
Decode Options. Selection of the decode options presents a further window as depicted in
Figure 12. Two options for full and partial decoding of the MPEG video streams are presented.
Note that as part of our implementation of extremely low delay encoding, GMS VETA products
do not employ the use of MPEG B frames. Therefore there is no functional difference between
the two options when using GMS encoding product. The option is left in the instance that the
GMS software decoder is used to view streams that have been encoded by hardware that
employs B frames.
Record to file. This option gives the user an option of recording the file that is being decoded
to disk. The user is prompted with a Windows standard “File Save” dialogue box. When
recording is active, this menu option is changed to “Stop Recording” which can be used to stop
writing to disk. See
Figure 13.