A method and apparatus for encoding a source media program is disclosed. In one embodiment, the method comprises the steps of transcoding the source media program to produce a constant video quality transcoded version of the media program, determining if a portion of constant video quality version of the transcoded media program fails to satisfy a constraint, if the portion of the transcoded media program fails to satisfy the constraint, adjusting at least one transcoding parameter of a set of transcoding parameters, transcoding the portion of the source media program according to the adjusted at least one transcoding parameter to produce a constant bit rate version of the portion of the transcoded media program, and substituting the constant bit rate version of the portion of the transcoded media program for the constant video quality portion of the transcoded media program.

A method and apparatus for encoding a source media program is disclosed. In one embodiment, the method comprises the steps of transcoding the source media program to produce a constant video quality transcoded version of the media program, determining if a portion of constant video quality version of the transcoded media program fails to satisfy a constraint, if the portion of the transcoded media program fails to satisfy the constraint, adjusting at least one transcoding parameter of a set of transcoding parameters, transcoding the portion of the source media program according to the adjusted at least one transcoding parameter to produce a constant bit rate version of the portion of the transcoded media program, and substituting the constant bit rate version of the portion of the transcoded media program for the constant video quality portion of the transcoded media program.

An apparatus for coding video information according to certain aspects includes a memory and a processor. The memory unit is configured to store video information associated with an enhancement layer (EL) and a corresponding reference layer (RL). The processor is configured to: code an EL picture in a current access unit (AU), the EL coded using a first standard that is different from a second standard that is used to code the RL, wherein the coding of the EL picture is based on information associated with a RL picture in the current access unit, the information associated with the RL picture provided by an external means and consisting of: (1) decoded sample values of the RL picture; (2) a representation format of the RL picture; and (3) an indication of whether the RL picture is an instantaneous decoding refresh (IDR) picture.

A method includes transcoding a first block from a spatial region. The first block is associated with a first block tree pattern defining a structure of splitting a block into smaller blocks. A bit string of bits for the first block tree pattern is included in an encoded bitstream. The method determines a location of the first block in the spatial region when the first block tree pattern of the first block can be reused for a second block tree pattern of a second block. The spatial region includes blocks and the location is based on the first block being in the spatial region. Information for the second block is included in the encoded bitstream that indicates the location of the first block in the spatial region. The location allows the bit string for the first block tree pattern to be retrieved for use to decode the second block.

A method includes transcoding a first block from a spatial region. The first block is associated with a first block tree pattern defining a structure of splitting a block into smaller blocks. A bit string of bits for the first block tree pattern is included in an encoded bitstream. The method determines a location of the first block in the spatial region when the first block tree pattern of the first block can be reused for a second block tree pattern of a second block. The spatial region includes blocks and the location is based on the first block being in the spatial region. Information for the second block is included in the encoded bitstream that indicates the location of the first block in the spatial region. The location allows the bit string for the first block tree pattern to be retrieved for use to decode the second block.

A method for composing an intermediate representation of a video sequence from at least two different representations of the video sequence, the at least two representations being spatially partitioned into a plurality of tiles, each tile being associated with compressed data in the representation. The method is such that the tiles can be decoded independently from one another and at a given time the various representations are partitioned identically. The method includes selecting, according to at least one selection criterion, a set of tiles forming a partition of the sequence from the at least two representations, and composing an intermediate representation of the video sequence from compressed data associated with the selected set of tiles. The method can be implemented in a video decoding terminal or broadcasting server.

A method for composing an intermediate representation of a video sequence from at least two different representations of the video sequence, the at least two representations being spatially partitioned into a plurality of tiles, each tile being associated with compressed data in the representation. The method is such that the tiles can be decoded independently from one another and at a given time the various representations are partitioned identically. The method includes selecting, according to at least one selection criterion, a set of tiles forming a partition of the sequence from the at least two representations, and composing an intermediate representation of the video sequence from compressed data associated with the selected set of tiles. The method can be implemented in a video decoding terminal or broadcasting server.

Provided is a method of determining whether an image is to be re-encoded, the method including obtaining a first quantization matrix from an image file including the image, the image being encoded by quantization based on the first quantization matrix including a plurality of first quantization parameters; obtaining a second quantization matrix from a re-encoding device, the second quantization matrix including a plurality of second quantization parameters and having the same size as the first quantization matrix; determining a comparison coefficient based on elements greater than ‘0’ among elements of a comparison matrix obtained by subtracting the first quantization matrix from the second quantization matrix; and determining that the image is to be decoded by inverse quantization based on the first quantization matrix and the decoded image is to be re-encoded by quantization based on the second quantization matrix, when the comparison coefficient is greater than a first threshold value.

Provided is a method of determining whether an image is to be re-encoded, the method including obtaining a first quantization matrix from an image file including the image, the image being encoded by quantization based on the first quantization matrix including a plurality of first quantization parameters; obtaining a second quantization matrix from a re-encoding device, the second quantization matrix including a plurality of second quantization parameters and having the same size as the first quantization matrix; determining a comparison coefficient based on elements greater than ‘0’ among elements of a comparison matrix obtained by subtracting the first quantization matrix from the second quantization matrix; and determining that the image is to be decoded by inverse quantization based on the first quantization matrix and the decoded image is to be re-encoded by quantization based on the second quantization matrix, when the comparison coefficient is greater than a first threshold value.

Methods are described to communicate source color volume information in a coded bitstream using SEI messaging. Such data include at least the minimum, maximum, and average luminance values in the source data plus optional data that may include the color volume x and y chromaticity coordinates for the input color primaries (e.g., red, green, and blue) of the source data, and the color x and y chromaticity coordinates for the color primaries corresponding to the minimum, average, and maximum luminance values in the source data. Messaging data signaling an active region in each picture may also be included.