Filter out small dimension images

[phedlund]

Hi,

I extract image urls from html and use ImagePrefetcher to download the images. What would be the best way to filter out images smaller than say 100x100px?

[onevcat]

ImagePrefetcher will only give you a list of skipped/downloaded images source, instead of giving you the actual images. Considering the fact that the loaded resource will be cached by default, maybe you can try:

ImagePrefetcher(urls: urls) { skippedResources, failedResources, completedResources in
  let smallImagesInMemoryCache = (skippedResources + completedResources).compactMap { r in
    ImageCache.default.retrieveImageInMemoryCache(forKey: r.cacheKey)
  }.filter { image in
    image.size.width < 100 && image.size.height < 100
  }
}

However, be caution that if you have lots of images, it might be possible that the downloaded images are removed from the memory cache but only stored in the disk cache. In this situation, you have to also use the disk cache related method to check them.