H.261

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H.261

(networking, standard)
A video compression standard developed by ITU-T before 1992 to work with integrated service digital network. Data is compressed at the rate of 64P kilobits per second, where P can range from 1 to 30 depending on the number of ISDN channels used. This standard was developed primarily to support video phones and video conferencing.

See also ivs.

http://crs4.it/~luigi/MPEG/mpeggloss-h.html#H.261.

H.261

An ITU standard for compressing an H.320 video transmission. The algorithm can be implemented in hardware or software and uses intraframe and interframe compression. It uses one or more 64 Kbps ISDN channels (Px64). H.261 supports CIF and QCIF resolutions. See H.323, CIF and codec.
References in periodicals archive ?
In addition, H261 is positioned to accept a proton from the attacking 4'-hydroxyl of lipid A disaccharide, and D99, which is hydrogen-bonded to H261, likely serves to increase its [pK.sub.a] [70].
Distances for hydrogen-bond and salt-bridge interactions are shown with distances in [Angstrom]ngstroms as follows: 3.0 from adenine N6 to Q240 O[epsilon] and 3.5 to R206 N[eta]1,3.0 from adenine N7 to Q240 N[epsilon], 2.8 from ribose 3'-hydroxyl to T52 O[gamma], 2.9 from [beta]-phosphate to S49 N and 3.1 to K51 N and 2.7 to T52 N and 2.6 to T52 O[gamma], 3.0 from [alpha]-phosphate to G50 N and 2.6 to Y187 O[eta], 3.4 from ribose 2'-hydroxyl to K280 N 2.8 from D99 O51 to H261 N5, 3.0 from K51 N[zeta] to D139 O[delta]1 and 2.7 to [gamma]-phosphate, 2.9 and 2.8 from [gamma]-phosphate to E100 O[epsilon]2/1, 3.2 from K280 N[zeta] to water, and 2.2, 3.0, and 3.0 from this water to the phosphates.
H261. "Allah has sent down the disease and the cure, and for