摘要:
Individual pixels in an image block undergo blending with film grain from a film grain block randomly selected from among a pool of previously established film grain blocks in accordance with a luma characteristic of the image block. Prior to blending, the selected film grain block undergoes deblocking by a deblocking filter (28). Following blending, a clipper clips the individual pixels prior to display. The pool of film grain blocks is created by scaling a set of film grain patterns in accordance with at least one parameter of a film grain information message that accompanies the image block.
摘要:
Bit-accurate creation of a film grain pattern occurs by first establishing a set of bit-accurate transformed coefficients. The set of bit-accurate transformed coefficients undergo frequency filtering and a subsequent bit-accurate inverse transformation to yield the film grain pattern.
摘要:
The addition of comfort noise to an image serves to hide compression artifacts. To facilitate comfort noise addition, supplemental information accompanying a video image contains at least one parameter that specifies an attribute regarding comfort noise. Typically, the supplemental information includes parameters that function to turn the comfort noise on and off, as well as to indicate the level of noise to add, based on the expected level of compression artifacts.
摘要:
There are provided methods and apparatus for bit-accurate seed initialization for pseudo-random number generators used in a video system. A method includes the steps of creating (205) a look-up table of PRNG seeds, and initializing (210) one of the PRNG seeds from the look-up table for a picture by accessing the look-up table using a value corresponding to an order of the picture.
摘要:
There is provided method and apparatus for film grain simulation for normal play and trick mode play for video playback systems. A method for simulating film grain in video includes the step of performing (214) film grain simulation on a sequence of decoded video pictures in decode order.
摘要:
The present invention provides a method and apparatus for reading film grain patterns in a raster order in film grain simulation including establishing a pseudo-random starting position, repeating the pseudo-random starting position for each line of a group of film grain blocks, and using a different pseudo-random starting position for each display line of a next group of film grain blocks. In various embodiments of the present invention, the different pseudo-random starting positions are triggered by resetting at least one seed value of a pseudo-random number generator implemented to determine said pseudo-random starting positions.
摘要:
The present invention provides methods for determining block averages in film grain simulation including determining block averages during a display process and determining block averages during a decoding process. The methods of the present invention exhibit different characteristics in terms of memory requirements and computational cost. More specifically, the first method uses no external memory, but requires either extra reads of the blocks, or internal memory in the display pipeline, while the second method requires extra memory bandwidth and extra external memory (e.g., RAM).
摘要:
Simulation of a block of film grain for addition to a block of an image occurs by first establishing at least one parameter at least in part in accordance with an attribute of the image block At least one at least one block of film grain is simulated from at least one film grain pattern generated in accordance with the at least one parameter. In particular, the film grain pattern is generated using a bit accurate technique.
摘要:
The present invention provides a method, apparatus and system for film grain cache splitting for film grain simulation. In one embodiment of the present invention a method for storing film grain patterns includes storing at least a first portion of film grain patterns in an internal memory and storing at least a second portion of the film grain patterns in an external memory. That is, in the present invention a method for film grain cache splitting for film grain simulation includes splitting the storage of film grain patterns between an internal cache and an external memory. In one embodiment of the present invention, the internal cache is integrated into an integrated circuit chip of a decoder.
摘要:
The present invention provides a method, apparatus and system for providing fast access to film grain patterns in a film grain simulation process including providing a first memory storing at least one film grain pattern and in response to a film grain pattern required by the film grain simulation process not being stored in the first memory, updating the first memory to obtain at least the required film grain pattern from at least a second memory. In one embodiment, the first memory is a local cache, the second memory is a film grain pattern database and a controller causes the examination of the local cache for a particular film grain pattern required in the film grain simulation process. In response to the required film grain pattern not being stored in the local cache, the controller causes the update of the local cache using the film grain pattern database.