In short, SmearHash takes a video and gives you a short list of strings (only 20-30 characters!) that represents the placeholder for that video. You do this on the backend of your service and store the strings list along with the video. When you send media to your client, you send both the URL to the video and the SmearHash strings list. Your client then takes the list and decodes it into an video that it shows while the real video is loading over the network. The strings are short enough that it comfortably fits into whatever data format you use. For instance, it can easily be added as a field in a JSON object.