The author of this web content discusses the complexities and potential pitfalls of bilinear upsampling and downsampling in image processing. They highlight the lack of consensus on the terminology and methodology in the field, leading to confusion and bugs in popular libraries like Tensorflow. The post delves into the nuances of different approaches to bilinear filtering, addressing issues like phase shifts, filter alignment, and half pixel offsets in GPU coordinates. The article offers a detailed analysis of signal processing aspects, such as zero insertion and post-filtering, shedding light on the challenges and implications of these operations in image resampling.
https://bartwronski.com/2021/02/15/bilinear-down-upsampling-pixel-grids-and-that-half-pixel-offset/