AR参考图像 - 图像的直方图很窄 [英] AR Reference image - The histogram of the image is narrow

问题描述

我正在将图像添加到ARKit项目中。但它给出了错误。

解决方案

您的图片内容不是有利于检测。 WWDC18上的

右边的图像存在多个问题，但分享了均匀颜色区域和窄直方图问题。对于人类而言，该图像非常容易识别，因为它使用我们识别空白背景上的实体形状的能力 - 尽管这种能力显然不是计算机视觉算法的优势。相反，你正在寻找许多细节 - 图像范围内的许多点具有高局部对比度。此外，您正在以灰度和低分辨率查看它，因为您希望在移动设备上以60 fps的速度运行。

这是图像上的直方图。左（转换为灰度后）：

这是右边图像的直方图（同样）：

直方图是一种量化好图像具有大量亮度等级的方法，其中坏图像具有仅有几种不同灰度的大块 - 你想要前者。

I am adding an image into ARKit project. But it gives error.

解决方案

You have an image whose content is not good for detection. There's a section in the WWDC18 talk What's New in ARKit 2 that talks about this and has some examples of what's good and what's not:

The image on the right has multiple problems, but shares the "uniform color regions" and "narrow histogram" issues you have. For a human, that image is pretty easy to recognize, because it uses our ability to identify solid shapes on empty backgrounds — that ability apparently isn't a strength of the computer vision algorithm in play here, though. Instead, you're looking for lots of detail — many points across the extent of the image with high local contrast. Also, you're looking at it in grayscale and at low resolution because you want to run at 60 fps on a mobile device.

Here's the histogram of the image on the left (after converting to grayscale):

Here's the histogram of the image on the right (likewise):

The histograms are a way of quantifying that the good image has lots of gradations of brightness, where the bad image has large chunks of only a few distinct shades of gray — you want the former.

这篇关于AR参考图像 - 图像的直方图很窄的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！