Nintendo Co., Ltd.

Ati Technologies Ulc

Farhad Fouladi

Timothy J Van Hook

Howard H Cheng

Robert J Moore

Mark M Leather

Anthony P DeLaurier

Winnie W Yeung

Martin Hollis

Gordon Elder, Iii

The present invention provides a scheme for compressing the color components of image data, and in particular, data used in multi-sampled anti-aliasing applications. Adjacent pixels are grouped into rectangular tiles, with the sample colors stored in compressed formats accessible via an encoded pointer. In one embodiment, duplicate colors are stored once. Unlike prior compression schemes that rely on pixel to pixel correlation, the present invention takes advantages of the sample to sample correlation that exists within the pixels. A memory and graphics processor configuration incorporating the tile compression schemes is also provided. The configuration defines the tile sizes in main memory and cache memory. In one embodiment, graphics processor relies on a Tile Format Table (TFT) to process incoming tiles in compressed formats. The present invention reduces memory consumption and speeds up essential and oft-repeated operations in rendering. Thus it is valuable in the design and manufacture of graphic sub-systems.

Method and apparatus for compression of multi-sampled anti-aliasing color data

A graphics system including a custom graphics and audio processor produces exciting 2D and 3D graphics and surround sound. The system includes a graphics and audio processor including a 3D graphics pipeline and an audio digital signal processor. A memory controller performs a wide range of memory control related functions including arbitrating between various competing resources seeking access to main memory, handling memory latency and bandwidth requirements of the resources requesting memory access, buffering writes to reduce bus turn around, refreshing main memory, and protecting main memory using programmable registers. The memory controller minimizes memory read/write switching using a 'global' write queue which queues write requests from various diverse competing resources. In this fashion, multiple competing resources for memory writes are combined into one resource from which write requests are obtained. Memory coherency issues are addressed both within a single resource that has both read and write capabilities and among different resources by efficiently flushing write buffers associated with a resource.

Graphics processing system with enhanced memory controller

A graphics system including a custom graphics and audio processor produces exciting 2D and 3D graphics and surround sound. The system includes a graphics and audio processor including a 3D graphics pipeline and an audio digital signal processor. The graphics system has a graphics processor includes an embedded frame buffer for storing frame data prior to sending the frame data to an external location, such as main memory. The embedded frame buffer is selectively configurable to store the following pixel formats: point sampled RGB color and depth, super-sampled RGB color and depth, and YUV (luma/chroma). Graphics commands are provided which enable the programmer to configure the embedded frame buffer for any of the pixel formats on a frame-by-frame basis.

Graphics system with embedded frame buffer having reconfigurable pixel formats

The present invention provides a scheme for compressing and decompressing the depth, or Z, components of image data. Image data is grouped into a plurality of tiles. A test is performed to determine if a tile can be compressed so that its size after compression is less than its size before compression. If so, the tile is compressed. A tile table includes a flag that can be set for each tile that is compressed. In one scheme, each tile comprises a 4&#xd7;4 block of pixels. For each pixel, the visible depth complexity is determined where each visible level of depth complexity is represented by a plane equation. Depending on the depth complexity, a compression scheme is chosen that stores multiple plane equations in cache lines. The compression scheme can be used with unsampled or multisampled data and provides higher levels of compression in multisampled environments.

Compression and decompression of data using plane equations

A graphics system including a custom graphics and audio processor produces exciting 2D and 3D graphics and surround sound. The system includes a graphics and audio processor including a 3D graphics pipeline and an audio digital signal processor. Techniques for efficiently buffering graphics data between a producer and a consumer within a low-cost graphics systems such as a 3D home video game overcome the problem that a small-sized FIFO buffer in the graphics hardware may not adequately load balance a producer and consumer&#x2014;causing the producer to stall when the consumer renders bit primitives. One aspect of the invention solves this invention by allocating part of main memory to provide a variable number of variable sized graphics commands buffers. Applications can specify the number of buffers and the size of each. All writes to the graphics FIFO can be routed a buffer in main memory. The producer and consumer independently maintain their own read and write pointers, decoupling the producer from the consumer. The consumer does not write to the buffer, but uses its write pointer to keep track of data valid positions within the buffer. The producer can write a read command to a buffer that directs the consumer to read a string of graphics commands (e.g., display list) stored elsewhere in the memory, and to subsequently return to reading the rest of the buffer. Display lists can be created by simply writing a command that redirects the output of the producer to a display list buffer.

Method and apparatus for buffering graphics data in a graphics system

Graphics system with embedded frame butter having reconfigurable pixel formats

A graphics processor includes an embedded frame buffer for storing frame data prior to sending the frame data to an external location, such as main memory. A copy pipeline is provided which converts the data from one format to another format prior to writing the data to the external location. The conversion may be from one RGB color format to another RGB color format, from one YUV format to another YUV format, from an RGB color format to a YUV color format, or from a YUV color format to an RGB color format. MPEG image data initially stored in main memory in a YUV format as a texture is transferred to the embedded frame buffer prior to initiating a copy-out process via the copy pipeline from the embedded frame buffer to an external frame buffer in main memory. During the copy-out process, pixels are converted from YUV format to an RGB format. A new texture image containing MPEG image data is placed in the embedded frame buffer prior to each successive copy out process operation so as to produce a streaming video image as a surface texture on at least a portion of a displayed object image.

Graphics system with copy out conversions between embedded frame buffer and main memory for producing a streaming video image as a texture on a displayed object image

A graphics system including a custom graphics and audio processor produces exciting 2D and 3D graphics and surround sound. The system includes a graphics and audio processor including a 3D graphics pipeline and an audio digital signal processor. The graphics processor includes an embedded frame buffer for storing frame data prior to sending the frame data to an external location, such as main memory. A copy pipeline is provided which converts the data from one format to another format prior to writing the data to the external location. The conversion may be from one RGB color format to another RGB color format, from one YUV format to another YUV format, from an RGB color format to a YUV color format, or from a YUV color format to an RGB color format. The formatted data is either transferred to a display buffer, for use by the video interface, or to a texture buffer, for use as a texture by the graphics pipeline in a subsequent rendering process.

Graphics system with copy out conversions between embedded frame buffer and main memory

A compact image element encoding format selectively allocates a bit field within the format to alternately encode either multi-bit alpha resolution or increased color resolution. This encoding technique may be advantageously used to allocate encoding bits to model semi-transparency while using those same bits for other purposes (e.g., higher color resolution) in instances where semi-transparency is not required (e.g., for opaque image elements). In one advantageous embodiment, the same encoding format can provide either RGB5 or RGB4A3, on an image-element-by-image-element basis. Applications include but are not limited to texture mapping in a 3D computer graphics system such as a home video game system or a personal computer.

Growing community of inventors

Los Altos Hills, CA, United States of America

Farhad Fouladi