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Testing DASH and HLS Streams on Linux

Dec 28, 2016

I’m developing a script to process some digitized and born digital video into adaptive bitrate formats. As I’ve gone along trying different approaches for creating these streams, I’ve wanted reliable ways to test them on a Linux desktop. I keep forgetting how I can effectively test DASH and HLS adaptive bitrate streams I’ve created, so I’m jotting down some notes here as a reminder. I’ll list both the local and online players that you can try.

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Client-side Video Tricks for IIIF

Oct 18, 2016

I wanted to push out these examples before the IIIF Hague working group meetings and I’m doing that at the 11th hour. This post could use some more editing and refinement of the examples, but I hope it still communicates well enough to see what’s possible with video in the browser.

IIIF solved a lot of the issues with working with large images on the Web. None of the image standards or Web standards were really developed with very high resolution images in mind. There’s no built-in way to request just a portion of an image. Usually you’d have to download the whole image to see it at its highest resolutions. Image tiling works around a limitation of image formats by just downloading the portion of the image that is in the viewport at the desired resolution. IIIF has standardized and image servers have implemented how to make requests for tiles. Dealing with high resolution images in this way seems like one of the fundamental issues that IIIF has helped to solve.

This differs significantly from the state of video on the web. Video only more recently came to the web. Previously Flash was the predominant way to deliver video within HTML pages. Since there was already so much experience with video and the web before HTML5 video was specified, it was probably a lot clearer what was needed when specifying video and how it ought to be integrated from the beginning. Also video formats provide a lot of the kinds of functionality that were missing from still images. When video came to HTML it included many more features right from the start than images.

As we’re beginning to consider what features we want in a video API for IIIF, I wanted to take a moment to show what’s possible in the browser with native video. I hope this helps us to make choices based on what’s really necessary to be done on the server and what we can decide is a client-side concern.

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IIIF Examples #1: Wellcome Library

Oct 1, 2016

As I’m improving the implementation of IIIF on the NCSU Libraries Rare and Unique Digital Collections site, I’m always looking for examples from other implementations for how they’re implementing various features. This will mostly be around the Presentation and Content Search APIs where there could be some variability.

This is just a snapshot look at some features for one resource on the Wellcome Library site, the example may not be good or correct, and could be changed by the time that you read this. I’m also thinking out loud here and asking lots of questions about my own gaps in knowledge and understanding. In any case I hope this might be helpful to others.

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Closing in on Client-side IIIF Content Search

Sep 25, 2016

It sounds like client-side search inside may at some point be feasible for a IIIF-compatible viewer, so I wanted to test the idea a bit further. This time I’m not going to try to paint a bounding box over an image like in my last post, but just use client-side search results to create IIIF Content Search API JSON that could be passed to a more capable viewer.

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Client-side Search Inside for Images with Bounding Boxes

Sep 24, 2016

It is possible to create a Level 0 IIIF Image API implementation with just static images and an info.json. And some institutions are probably pre-creating Presentation API manifests or even hand-crafting them. All that’s required then is to put those files up behind any web server with no other application code running and you can provide the user with a great viewing experience.

The one piece that currently requires a server-side application component is the IIIF Content Search API. This usually involves a search index like Solr as well as application code in front of it to convert the results to JSON-LD. I’ve implemented search inside using the content search via Ocracoke. With decent client-side search from libraries like lunr.js it ought to be possible to create a search inside experience even for a completely static site.

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