Information processing device

Abstract

An information processing device in which memory bands can be significantly cut. In the present device, an access determining / managing portion (105) determines whether or not write data meets access determination conditions when write-accessing a memory (104), and manages this determination result and access location data (an address in the memory (104)) during the write access as access determination results (107), and does not perform a write access if the write data does not meet the access determination conditions. On the other hand, the access determining / managing portion (105) references the access determination results (the access location data and determination result) when read-accessing the address, and if the access determination results meet the access determination conditions when read-accessing the address, the data determined by the access determining conditions is returned to the master, without read-accessing the memory (104).

Description

technical field [0001] The present invention relates to an information processing apparatus having a memory. Background technique [0002] In recent years, for LSIs (Large scale Integration circuits) that process digital images, as the size of images to be processed increases, insufficient memory bandwidth (the number of accesses per unit time) has become a big problem. [0003] For example, taking the chroma key (key color) composition, which is one of the image composition methods, as an example, use figure 1 Explain the problem. Chroma key composition is a method of synthesizing two images by removing only a specific color called chroma key from an image and inserting another image. Any color can be set as a chroma key. [0004] figure 1 It shows the case where the image C is generated by combining the image A and the image B stored in the memory. Set the chroma key data for image A. The image A is generated by the processor (CPU: Central Processing Unit) 1 , that i...

AI Technical Summary

Problems solved by technology

[0011] However, in the above-mentioned technologies described in Patent Document 1 and Patent Document 2, the number of unnecessary write accesses can be reduced, but the number of read accesses cannot be reduced.

In other words, the technique described in Patent Document 1 omits the writing process when the read data and the revised data match at the time of reading / modifying / writing, and does not consider reducing memory access in the reading process at all. number

In addition, in the technique described in Patent Document 2, write accesses are reduced, but when reading out the clear value at the time of reading, the previous image data is returned, that is, it is read and it is determined whether it is clear data and replaced. Memory band reduction has limited effect

Images