A method of decoding an encoded stream into a reconstructed output signal is provided, the method comprising: receiving a first output signal decoded from a first base encoded stream according to a first codec; receiving a level encoded stream; decoding the level encoded stream to obtain a set of residuals; and, combining the set of residuals with the first output signal to generate a reconstructed signal, wherein the decoding the level encoded stream comprises: decoding a set of quantized coefficients from the level encoded stream; dequantizing the set of quantized coefficients.

Block-based, low latency rate control for an encoding system in which a wavelet transform decomposes pixel blocks into subbands stored as subbands in wavelet blocks (WBs) for encoding. Quantization parameters (QPs) for the subbands in each WB are estimated using a method that minimizes wavelet-inverse distortion given a rate bound. For each subband, a rate curve is generated based on an unquantized DCT histogram and bit count statistics for the subband, and a distortion curve is generated based on the unquantized DCT histogram and a distortion estimate for the subband that is estimated using a masked estimator. Once the rate-distortion curves for the subbands are generated, a bisection search may be used to find a point on each curve where the slope is the same for all the curves. The QPs associated with those equally sloped points are the global minimizing QPs for the wavelet block.

In one embodiment, an apparatus comprises a storage device and a processor. The storage device stores a plurality of images captured by a camera. The processor: accesses visual data associated with an image captured by the camera; determines a tile size parameter for partitioning the visual data into a plurality of tiles; partitions the visual data into the plurality of tiles based on the tile size parameter, wherein the plurality of tiles corresponds to a plurality of regions within the image; compresses the plurality of tiles into a plurality of compressed tiles, wherein each tile is compressed independently; generates a tile-based representation of the image, wherein the tile-based representation comprises an array of the plurality of compressed tiles; and stores the tile-based representation of the image on the storage device.

The invention relates to a method and apparatus for image compression, particularly to an improved block-coding apparatus and method for image compression. Image compression systems such as JPEG and JPEG2000 are known and popular standards for image compression. Many of the advantageous features of JPEG2000 derive from the use of the EBCOT algorithm (Embedded Block-Coding with Optimized Truncation). One drawback of the JPEG2000 standards is computational complexity. This application discloses a relatively fast block-coding algorithm, particularly as compared with the standard JPEG2000 EBCOT algorithm. Computational complexity is reduced.

A portion of a first wavelet transform associated with a first frame in a sequence is compressed to produce a first compressed or modified portion of the first wavelet transform. The first modified portion is stored in the memory. A portion of a second wavelet transform associated with a second frame in the sequence is obtained. A set of differences between the portion of the second wavelet transform and the first compressed portion of the first wavelet transform is determined. A second compressed portion is generated based at least in part on the set of differences. A subset of a set of image data is provided to be displayed on a display device based at least in part on the second compressed portion.

Implementations related to coding and/or decoding image data employing video coding with embedded motion are disclosed.

Implementations related to coding and/or decoding image data employing video coding with embedded motion are disclosed.

Computer processor hardware receives a first set of adjustment values. The first set of adjustment values specify adjustments to be made to a predicted rendition of a signal generated at a first level of quality to reconstruct a rendition of the signal at the first level of quality. The computer processor hardware processes the first set of adjustment values and derives a second set of adjustment values based on the first set of adjustment values and a rendition of the signal at a second level of quality. The second level of quality is lower than the first level of quality.

Computer processor hardware receives a first set of adjustment values. The first set of adjustment values specify adjustments to be made to a predicted rendition of a signal generated at a first level of quality to reconstruct a rendition of the signal at the first level of quality. The computer processor hardware processes the first set of adjustment values and derives a second set of adjustment values based on the first set of adjustment values and a rendition of the signal at a second level of quality. The second level of quality is lower than the first level of quality.

A video encoding system in which pixel data is decomposed into frequency bands prior to encoding. The frequency bands are organized into blocks that are provided to a block-based encoder. The encoded frequency data is packetized and transmitted to a receiving device. On the receiving device, the encoded data is decoded to recover the frequency bands. Wavelet synthesis is then performed on the frequency bands to reconstruct the pixel data for display. The system may encode parts of frames (tiles or slices) using one or more encoders and transmit the encoded parts as they are ready. A pre-filter component may perform a lens warp on the pixel data prior to the wavelet transform.