Main Content

本页对应的英文页面已更新,但尚未翻译。 若要查看最新内容,请点击此处访问英文页面。

图像变换

执行傅里叶、离散余弦、Radon 和扇形波束变换

图像变换将图像从一个域转换到另一个域。图像通常在空间域中获取和显示,其中相邻像素表示场景的相邻部分。不过,也可以在其他域中获取图像,例如其中相邻像素表示相邻频率分量的频域,或其中相邻像素表示相邻投影角度和径向距离的 Hough 域。在非空间域中查看和处理图像可以识别在空间域中不容易检测到的特征。

函数

houghHough 变换
houghlines基于 Hough 变换提取线段
houghpeaksIdentify peaks in Hough transform
dct2二维离散余弦变换
dctmtxDiscrete cosine transform matrix
fan2paraConvert fan-beam projections to parallel-beam
fanbeamFan-beam transform
idct22-D inverse discrete cosine transform
ifanbeamInverse fan-beam transform
iradonInverse Radon transform
para2fanConvert parallel-beam projections to fan-beam
radonRadon 变换
fft2二维快速傅里叶变换
fftshift将零频分量移到频谱中心
ifft2二维快速傅里叶逆变换
ifftshift逆零频平移

主题

傅里叶变换

了解傅里叶变换及其在图像处理中的一些应用,尤其是在图像滤波中。

离散余弦变换

了解图像的离散余弦变换 (DCT) 及其应用,特别是在图像压缩中的应用。

Hough Transform

The Hough transform detects lines in an image, including lines tilted at arbitrary angles from vertical and horizontal. The Hough transform tends to be quick, but can exhibit artifacts.

Radon Transform

The Radon transform detects lines in an image, including lines tilted at arbitrary angles from vertical and horizontal. The Radon transform tends to be more accurate at the cost of longer computation time.

The Inverse Radon Transformation

The inverse Radon transform reconstructs an image from a set of parallel-beam projection data across many projection angles.

Fan-Beam Projection

Use fan-beam projection and reconstruction when projections of an image are acquired along paths radiating from a point source. Medical tomography is a common application of fan-beam projection.

特色示例