Optimized two-dimension DMA transmission method especially for access to image block

Abstract

The invention discloses a two-dimensional DMA method special for data optimization of MAE access image block, which can obviously accelerate the transmission speed of the image block when processing byte alignment and automatically fill up the subimage block data beyond the image boundary. The method mainly comprises the following steps: (1) gaining the initial work address of the actual poke and access of poke edge and access edge according to the leading byte addresses of the poke edge and the access edge; (2) gaining poke times of the poke edge and access times of the access edge according to the leading byte addresses of poke edge and access edge and transmit data in each row; (3) initializing the row counting value and line counting value of the poke edge and access edge; (4) reading data of poke edge and writing in adaptive FIFO; (5) writing data in the adaptive FIFO; (6) continuing to transmit the data in next row if the adaptive FIFO is not full. The method can increase the transmission speed by four times and ensure the accuracy of data access.

Description

technical field [0001] The invention relates to a two-dimensional DMA transmission method optimized for accessing image blocks on a video communication hardware MAE (media accelerator engine). In particular, it relates to a transmission method when the MAE accesses sub-image block data with byte alignment at high speed and the sub-block data boundary of the image exceeds the image boundary. Background technique [0002] In traditional DMA transmission, DMA can process data in parallel with the main processor, reducing the load on the processor, and because it is direct memory access, the transmission speed is faster than the speed of CPU access to data, so it generally requires large-scale access When data is transferred, DMA is used for transmission. [0003] However, the traditional DMA data transmission speed cannot adapt to the high-bandwidth, high-transmission-rate image and video data transmission requirements gradually. Under ordinary two-dimensional DMA transmission...

AI Technical Summary

Problems solved by technology

However, in the image access of the multimedia acceleration engine, because it is often necessary to fetch sub-image blocks for processing, or store the processed sub-image blocks in the memory, and some of these sub-image blocks are byte-aligned, If ordinary two-dimensional DMA is used, the transmission speed will be greatly reduced, and in some processing situations, the boundary of the sub-image block is not within the boundary of the original image. count error

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