根据客户的设计图像确定条纹色彩的正确RGBA值？

I often get given mockup images that define how an iPhone app is supposed to look. These can come from as many different methods as there are projects, sometimes balsamiq or even hand-drawn, sometimes Photoshop. One thing that is common is a bar tint color specified usually to match some corporate branding or overall app design.I often get given mockup images that define how