Subject: High speed real-time streaming playback
Date: Wed, 13 Jun 2007 19:12:34 -0700
From: David Burg <daviburg@windows.microsoft.com>
To: <mtfuji5@avc-pioneer.com>
CC: T10 Reflector <t10@t10.org>
X-Message-Number: 7850
Formatted message: HTML-formatted message

Hello,
I would like to better understand the high speed real-time streaming
playback proposal.
The presentation material from last week's meeting claims that
"Currently, Real-Time Stream model is designed only for 1x speed."
However the current section 8 on real-time streaming in Mt Fuji is
generic and does not make any mention of 1x speed.
Also, this presentation material shows a graph of data rate on radius
with the data rate dropping below the "3x" data rate. There is however
already in Mt Fuji the possibility for both the host to request the
logical unit to exactly match the requested performance (exact bit of
set performance) and for the logical unit to return performance
descriptors to describe the same data rate on radius (get performance
type field 00h). Accordingly it seems that in the sample sequence from
the presentation step 2 is not necessary and all other steps can already
be performed today:
"1. The host reads data on the media.
2. If the data requires high speed Real-Time Stream playback, the host
checks the ability by checking HSSR bit setting in Real-Time
Streaming Feature.
3. The host sets the minimum data rate by using SET STREAMING
command.
4. The host checks the minimum data rate by using GET
PERFORMANCE command.
5. The host issues READ (12) with Streaming bit = 1."
Best regards,
David Burg.