ISMA Profiles - A Practical Guide to Video and Audio Compression - page 678

IP Transport of audio and video using SDP and RTP/RTSP

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Storage in MPEG-4 file format (.mp4)

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The ISMA 2.0 specification begins to look at open standards-based multimedia in the
enterprise with these work items:

Rich-media object synchronization

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Closed captioning

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Enterprise DRM

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Live server failover specification

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H.3 ISMA 1.0 Profiles 0 and 1

The Internet Streaming Media Alliance (ISMA) was formed by a group of interested com-
panies who wished to simplify the development of streaming services, servers, and play-
ers by defining some constraints on performance and bit-rate requirements. These address
the optimal service levels for modem-delivered video, broadband-delivered video, and
higher-bit-rate services on fast networks. The two profiles that have been published to
date are compared in Table H-2.
The parameters specified by these profiles are carefully chosen to be practical, given
the current technological capabilities. They are developed in consultation with other stan-
dards bodies. Note that the 3GPP mobile profile is substantially the same as ISMA profile 0
but is designed for mobile devices.

H-2 ISMA Version 1.0 Profiles

Attribute Profile 0 Profile 1

Target Narrowband and wireless Broadband. This is a superset of

applications. Profile 0 and allows a richer

browsing experience.

Codec MPEG-4 Part 2 video, Simple MPEG-4 Part 2 video, Simple

Profile, Level 1 Profile, or Advanced Simple

Profile, Level 3

Raster size 176 × 144 (QCIF) 352 × 288 (CIF)

Frame rate 15 fps 30 fps (assumed to mean 25 in

Europe)

Audio High-Quality Audio Profile at High-Quality Audio Profile at

Level 2. CELP and Level 2. CELP and low-

low-complexity AAC. complexity AAC.

Sample rate Up to 48 KHz Up to 48 KHz

Max bit rate 64 Kbps 1.5 Mbps