Method and apparatus for communicating an image over a network with spatial scalability
AssigneeMagor Communications Corporation
InventorsXiaodong Huang, Mojtaba Hosseini, Patrick White
Life of this patent
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Abstract
Visual information over a network by filtering a full resolution image signal to produce a series of sub-bands, wherein at least one of the sub-bands constitutes a base sub-band representing an image of reduced resolution and wherein additional sub-bands carry higher resolution information. At least the base sub-band is transmitted to a far end endpoint to permit image reconstruction at the far end endpoint at a degree of resolution dependent on the number of sub-bands used to reconstruct the image.
Claims25
A method of transmitting video information over a network comprising:
- temporarily storing a full resolution video signal in a frame buffer;
- filtering the full resolution video signal by passing said full resolution video signal from the frame buffer through a filter bank to a series of buffers containing sub-banded video signals, said filter bank including pairs of high pass and low pass filters arranged in a cascaded arrangement, each pair of filters being followed by a downsampler, said filter bank being configured such that at least one of the sub-bands constitutes a base sub-band representing a video image of reduced resolution and additional sub-bands carry higher resolution information;
- passing the sub-band video signals through respective separate code operating independently of each other to encode the sub-bands in parallel into a series of encoded sub-bands for transmission as separate video streams over the network;
- and
- transmitting at least the encoded base sub-band to a far end endpoint to permit video reconstruction at the far end endpoint at a degree of resolution dependent on the number of sub-bands used to reconstruct the video image.
A method of receiving visual information over a network from a remote endpoint offering a full resolution image signal decomposed into a series of encoded sub-bands as separate data streams, wherein at least one of the encoded sub-bands constitutes an encoded base sub-band representing an image of reduced resolution and wherein additional encoded sub-bands carry higher resolution information, comprising:
- determining the required resolution of an image to be displayed;
- establishing two or more connections to the remote endpoint to receive at least the encoded base-band and at least one additional encoded sub-bands to reconstruct an image at the required resolution;
- decoding the received encoded sub-bands in a parallel arrangement of separate decoders operating independently of each other to produce a plurality of image signals corresponding to said respective encoded sub-bands;
- temporally aligning the parallel image signals in a collector;
- and
- passing said image signals through an inverse filter bank comprising cascaded pairs of high and low pass filters followed upsamplers to reconstruct the image at the required resolution.
An apparatus for transmitting visual information over a network comprising:
- a filter bank for filtering a full resolution image signal to produce a series of sub-bands, wherein at least one of the sub-bands constitutes a base sub-band representing an image of reduced resolution and wherein additional sub-bands carry higher resolution information;
- a plurality of separate encoders in parallel configured to operate independently of each other to encode said respective sub-bands;
- and
- one or more transmitters for transmitting at least the encoded base sub-band to a far end endpoint to permit image reconstruction at the far end endpoint at a degree of resolution depending on the number of sub-bands used to reconstruct the image,
- wherein the sub-bands are dynamically configurable so that the image resolution conveyed by the base sub-band matches the resolution of an endpoint in the network having the lowest resolution.
An apparatus for transmitting visual information over a network comprising:
- a filter bank for filtering a full resolution image signal to produce a series of sub-bands, wherein at least one of the sub-bands constitutes a base sub-band representing an image of reduced resolution and wherein additional sub-bands carry higher resolution information;
- a plurality of separate encoders in parallel configured to operate independently of each other to encode said respective sub-bands;
- and
- one or more transmitters for transmitting at least the encoded base sub-band to a far end endpoint to permit image reconstruction at the far end endpoint at a degree of resolution depending on the number of sub-bands used to reconstruct the image,
- wherein the filter bank comprises a cascaded arrangement of pairs of high and low pass filters and a series of buffers for temporarily storing data in each sub-band.
An apparatus for receiving visual information over a network from a remote endpoint offering a full resolution image signal decomposed into a series of encoded sub-bands as separate data streams, wherein at least one of the encoded sub-bands constitutes an encoded base sub-band representing an image of reduced resolution and wherein additional encoded sub-bands carry higher resolution information, comprising:
- a plurality of receivers for receiving the encoded base-band and or more additional encoded sub-bands;
- a parallel arrangement of separate decoders configured to operate independently of each other and to produce a series of parallel image signals corresponding to said respective encoded sub-bands;
- a collector for temporally aligning the parallel image signals;
- and
- an inverse filter bank for recombining the aligned image signals into an image having a degree of resolution dependent on the number of sub-bands used to reconstruct the image, said inverse filter bank comprising cascaded pairs of high and low pass filters followed by upsamplers.
Dependencies are inferred from the claim text.