rgb24_to_yv12_mmx函数中stride参数是干嘛的？顶也有分哈

rgb24_to_yv12_mmx(uint8_t * const y_out,uint8_t * const u_out,uint8_t * const v_out,const uint8_t * const src, rgb24_to_yv12_mmx(uint8_t * const y_out,uint8_t