UIImagePNGRepresentation 和 UIImageJPEGRepresentation

EtherCAT同步模式实战:如何用TwinCAT配置DC-Synchronous模式(附时序图详解) 本文详细解析了如何在TwinCAT环境中配置EtherCAT的DC-Synchronous同步模式,实现纳秒级同步精度。通过硬件准备、参数配置和高级调优步骤,帮助工程师解决工业自动化中的同步挑战,提升运动控制性能。 阅读详情
在Iphone上有两种读取图片数据的简单方法: UIImageJPEGRepresentation和UIImagePNGRepresentation. 

UIImageJPEGRepresentation函数需要两个参数:图片的引用和压缩系数.而UIImagePNGRepresentation只需要图片引用作为参数.通过在实际使用过程中,比较发现: UIImagePNGRepresentation(UIImage* image) 要比UIImageJPEGRepresentation(UIImage* image, 1.0) 返回的图片数据量大很多.譬如,同样是读取摄像头拍摄的同样景色的照片, UIImagePNGRepresentation()返回的数据量大小为199K ,而 UIImageJPEGRepresentation(UIImage* image, 1.0)返回的数据量大小只为140KB,比前者少了50多KB.如果对图片的清晰度要求不高,还可以通过设置 UIImageJPEGRepresentation函数的第二个参数,大幅度降低图片数据量.譬如,刚才拍摄的图片, 通过调用UIImageJPEGRepresentation(UIImage* image, 1.0)读取数据时,返回的数据大小为140KB,但更改压缩系数后,通过调用UIImageJPEGRepresentation(UIImage* image, 0.5)读取数据时,返回的数据大小只有11KB多,大大压缩了图片的数据量 ,而且从视角角度看,图片的质量并没有明显的降低.因此,在读取图片数据内容时,建议优先使用UIImageJPEGRepresentation,并可根据自己的实际使用场景,设置压缩系数,进一步降低图片数据量大小.
骑砍Ⅱ霸主MOD开发(16)-FaceKey&BannerKey 摘要:本文介绍了FaceKey人物模型和BannerKey旗帜模型的生成流程。FaceKey通过序列化参数生成人物模型,包括头部(脸部、嘴、睫毛、眼睛)、眉毛、头发、身体和躯干等组件,每个部分通过特定标签和骨骼绑定实现。BannerKey则通过解析参数生成旗帜模型,包括模型、贴图和颜色等元素。两种模型都采用参数化设计和XML配置文件实现模型生成与定制。 阅读详情

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