Sony Ziris Canvas BZSQ-VW001, Инструкция по установке и эксплуатации

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Known Issues
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Known Issues
Maximum Bit Rates for Video
The maximum bit rates specified in the Supported Media
Formats section are the average bit rate limits enforced by
Ziris Create for video items playing at the same time
within a presentation. There are several circumstances not
enforced by Ziris Create when the bit rate may be allowed
to exceed the capabilities of Ziris View.
• During the 4 second initialisation period before a video
starts to play.
• When one presentation ends (or at the point it is
interrupted in the case of default content) with video at a
high bit rate and the next presentation starts with video
at high bit rate.
• Video for Ziris View is normally encoded using variable
bit rate but Ziris Create enforces the limit based on the
average bit rate. There may be spikes where the bit rate
exceeds the maximum.
It is always recommended to preview your presentations
and schedule on a 'preview' Ziris View channel before
uploading to a 'live' channel, at least until you are familiar
with the capabilities and limits of Ziris View on
PLAYSTATION®3. If it is not possible to decode video
fast enough, Ziris View may stop displaying a particular
video item and log an error message such as:
ERROR Video "../ingest_videos/myvideo.mpg" stopped
after too many failures to get correct picture for display
It is not recommended to encode all your content at the
maximum supported bit rate. For example, 20-25 Mbit/s is
probably sufficient for full screen 1080p HD video. Lower
resolution video requires less bit rate. Higher bit rates will
take longer to download, require more disk space and
increase the chance of playout problems. At some point,
depending on the resolution and original quality of the
source video, using higher bit rates will not necessarily
improve the visual quality on the display.
Change of current presentation is
not synchronized
If you upload new scheduled or default content to a Ziris
View PS3 channel, the download is unlikely to complete
and take effect at the same time on different PS3's.
Therefore, if the update results in a change to the current
playing presentation, multi-screen presentations will not
appear synchronised until all PS3's have downloaded the
update.
If multi-screen synchronization is required at all times, it is
recommended to always schedule new content sufficiently
in advance to allow time for Ziris View to download the
content before its play time. When changing default
content, a presentation can be scheduled while the new
content is being downloaded so that all Ziris View PS3's
starts playing the new default content at the time the
scheduled presentation ends. The old default presentation
could be scheduled to play at the same time as it would
play as default content if required.
Although default content is not given an explicit time to
play, Ziris View implicitly schedules it based on the
previous scheduled item end time in order to synchronise
multiple players. Therefore, removing the last presentation
scheduled before the current time may affect the play time
of any current playing default content and force Ziris View
to be re-schedule it.
Deleting large files (> 2GB) may
interfere with playout.
When a large file is deleted from the PLAYSTATION®3
hard disk, there is a significant impact on the read
performance for other files being read at the same time.
This is particularly a problem when playing high bit rate
video. Ziris View periodically deletes expired media,
downloads new media and waits the specified Content
Download Interval (see Settings) before checking again.
By default, Ziris Create sets the delete times automatically
based on when media is scheduled to play. This means that
Ziris View may delete files at any time of day. When a
large file is deleted, you may get an error for a current
playing video such as:
ERROR Video "../ingest_videos/myvideo.mpg" stopped
after too many failures to get correct picture for display.
If possible, it is recommended to encode your longer
duration content as several shorter clips (e.g. up to 10
minutes depending on bit rate) to avoid this delete issue.
Shorter files are also easier to manage and give you more
flexibility in authoring your presentations in Ziris Create.
Shorter files allow you to re-order, add or remove clips
without re-encoding large video files.
In order to give the user some control over this problem, it
is possible to specify a delete time window for Ziris Create
to ensure that media always expires at a known time of
day.
The delete time window can be set using a command line
utility on the Ziris Create server: