海思3519 sample困惑理解

1）

问题：vi dump时为什么需要做一个VGS缩放动作？

原因：因为当vi get下来一帧是压缩后的YUV时，需要用VGS转成原始YUV数据，所以才调用。不然根本不需要，直接保存将SP420存成P420即可。SP420:Y... VUVU...，P420:Y... UU... VV...

2）

stride addr

/mnt/tools # ./vi_dump

NOTICE: This tool only can be used for TESTING !!!
Usage:  ./vi_dump [DataType] [ViChn] [FrmCnt]. sample: ./vi_dump -y 0 5
         To see more usage, please enter: ./vi_dump -h

    printf("\n\n%d,%d,%d,%d,%d,%#x,%#x,%#x,%#x,%#x,%#x,%d,%d,%d,\n",stFrame.stVFrame.u32Width,\
                stFrame.stVFrame.u32Height,\
                stFrame.stVFrame.u32Stride[0],\
                stFrame.stVFrame.u32Stride[1],\
                stFrame.stVFrame.u32Stride[2],\
                stFrame.stVFrame.u32PhyAddr[0],\
                stFrame.stVFrame.u32PhyAddr[1],\
                stFrame.stVFrame.u32PhyAddr[2],\
                stFrame.stVFrame.pVirAddr[0],\
                stFrame.stVFrame.pVirAddr[1],\
                stFrame.stVFrame.pVirAddr[2],\
                stFrame.stVFrame.u32Field,\
                stFrame.stVFrame.enCompressMode,\
                stFrame.stVFrame.enPixelFormat);



3840,2160,3840,3840,0,0x85a7b500,0x86264500,0,0xc8801500,0xc8fea500,0,4,0,23,
Dump YUV frame of vi chn 0 to file: "./vi_chn_0_3840_2160_p420_1.yuv"
stride: 3840,3840
saving......Y......U......V......done 1782!
/mnt/tools #

亮度stride和色度stride都是3840,且stride[2]是0,[2]地址也是无效的0