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Seems like Tumblr removed this option?? Not very accessible...

Hey!

Good news: You can now add alt text to every photo and GIF you upload to a post with your Tumblr iOS or Android app.

What?

Alt text! It’s a textual alternative to a photo or GIF, so anyone who uses a screen reader will know what you’ve posted. If you post, say, a long Furby sitting on a couch, you might provide alt text that says “a long Furby sitting on a couch” so anyone who needs to use a screen reader gets to join in on the fun. Keep it short, keep it descriptive. 

How?

Easy-peasy. When you add an image or GIF to a post or reblog on Tumblr in the iOS or Android app, you’ll see a meatballs menu (●●●) pop up in the lower right-hand corner of your image or GIF. Tap it, then select “Add alt text.” 

Why?

We’re continuing our efforts to make Tumblr more accessible in accordance with the Web Accessibility Initiative of the World Wide Web Consortium. They’re an initiative that sets standards for accessibility for people who may need assistance using the internet.

Happy alt texting, Tumblr!

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In case you missed the session at AMIA 2020, here is the full recorded DVRescue presentation. Presented by Ashley Blewer, Libby Hopfauf, Dave Rice and Andrew Weaver.

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Today, Dave Rice and Libby Hopfauf presented on DVRescue at the Library of Congress Labs Informal A/V Summit. You can view the slide deck here. LoC Labs will post the full recording of the summit here in the next few months. 

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DVRescue Workshop #2: Capturing DV with dvcapture

This blog post is part of a series of workshops conducted as part of the DVRescue project. These workshops were originally intended to be held in person over the course of several days, but due to COVID-19, they are held online with members of the DVRescue team and participating organizations.

DVRescue's second workshop focused on capturing DV tapes and the DVRescue tool, dvcapture.

DV is captured in many different ways, both on the hardware and software sides of things.

There have been many software options over DV's lifetime, such as:

Adobe Premiere

Apple Final Cut Pro

avcvideocap

avfoundation

dvgrab

dvhscap

Kino

LifeFlix

LiveCapturePlus

MPEG Stream Clip

Most of these tools no longer work on modern operating systems. For example, on macOS there is no post-Catalina macOS-based DV capture tool (other than with DVRescue and vrecord). All have other issues that make capturing difficult work.

A few example of problems with capturing DV include:

Timecode breaks

"Capture has been stopped?" error for every frame (Premiere)

can't monitor audio during playback

make a new section when there's no contiguous timecode

creating files with chunks of missing data

outputs DV with MOV under the hood, but would fail doing the transcode

changing standards as capturing is happening

weird frames

dropped frames

General bugginess and crashing

Not cross-compatible

Part of DVRescue's focus is on making a capturing tool that works well, continues to be supported by archivists, and works on all major modern operating systems (Linux, macOS, Windows). The capture tool should be able to work as a command-line application and an easy-to-use, friendly graphical user interface (GUI).

DVRescue relies on tools within the FFmpeg framework to capture files. Part of this workshop involved a demonstration of avfctl (av foundation control), one of the tools used underneath dvcapture. avfctl is a tiny program that does deck control and capture on a mac, using avfoundation.

This ability to control the DV deck and capture material is currently available in the latest release (v2020-07-01) of vrecord.

Demo Video: https://youtu.be/LJ4JiZyM4sQ

There are some features that would be nice to have when capturing DV that arose during this workshop, including:

creating multiple captures and automatically consolidating them to get the best transfer possible (TODO next)

being able to automatically stop the transfer when running into a certain amount of time of blank tape

being able to page through and find the next bit of content, storing a few blank frames in between

making a continuous transfer from multiple tapes

Error tallies; Timeline of errors

Waveforms, vectorscopes, or audio meters

Timecode details

Reporting

Here are some additional questions the DVRescue team are thinking about while focusing on how to best capture DV: 

What should be included in documentation for setting up a dv capture station?

What suggestions to give a user before transferring a tape?

Should we ask for more information from the user before capture?

What options should be considered during capture?

Should the capture auto-start after a certain amount of time if there's no frames coming (like at the end of the tape)?

Current capture (in vrecord and avfctl) is from the current point of the tape til it is stopped? Should we add other automated scenarios (repack then get whole tape or timecode range? rewind after done?)

The content is already digital, so is it worth showing scopes or other complex visualizations like vrecord done during capture?

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Using DV Capture in vrecord

For those of you who haven’t tried it out yet, here’s a run-down on capturing DV tapes in vrecord!

Basic Instructions

To capture DV formats in vrecord (when installed in macOS), you will need to have your DV deck connected directly to your computer via FireWire input. Make sure your deck is in “Local” mode. At this time, vrecord is not equipped with tape control, so you will need to manually start and stop the tape just like with analog capture in vrecord.

To select the deck you would like to use, go into the configuration mode either by:

run vrecord -e

clicking on the "Edit Settings" button in the GUI (run vrecord -g)

Switch from the "Decklink" tab to the "DV" tab under "Input Options" at the top of the configuration window.

Select the name of the DV device you want to use from the list.

Specify the playback, sidecar, file naming, recording event and directory options as you normally would for vrecord. For details see Editing Settings.

Click "OK" to save.

You can then run passthrough and record modes the same as you would with analog videotape. Please note that if the timecode does not start at the very beginning of the tape, the record mode viewer will not open until the timecode is detected (as soon as the counter starts moving on your deck, the viewer window should pop-up).

To end the capture, exit out of the ffmplay viewer window by clicking the red “x” in the upper left hand corner. Please note that if your video ends on a freeze frame of video, you will need to either start rewinding the tape or terminate the terminal window in order to exit capture (otherwise, you will end up with the spinning rainbow wheel of doom). 

Tips & Tricks

Currently, some users are experiencing issues with capturing that results in dropped frames or presentation time stamp (PTS) discontinuities. Here are a few variables to test if you encounter this issue:

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DVRescue Workshop #1: dvpackager and dvloupe

This blog post is part of a series of workshops conducted as part of the DVRescue project. These workshops were originally intended to be held in person over the course of several days, but due to COVID-19, they are held online with members of the DVRescue team and participating organizations.

DVRescue is made up of a series of tools that support archivists in capturing, managing, and packaging DV material. For dvpackager, we aspire to be able to guide archivists through the setup and transfer processes, so we can collectively get more tapes transferred off their physical carriers, have those digital transfers be of higher quality, and allow archivists to be able to perform quality control on the content.

This first workshop focused on the dvpackager and dvloupe tools within DVRescue.

Around a decade ago, there were a lot of different options for transferring DV tape but they have all been abandoned. For now, archivists use old technology and hope that it does not stop working when they update their computers (or refrain from performing any software updates in anticipation of this). 

The software that previously existed to transfer DV tape to computers falls into two categories: capture everything into one DV stream, or (with tools such as Apple Final Cut Pro or Adobe Premiere), write all of the data into a container such as Quicktime MOV.

DVRescue takes a different approach and captures a DV stream and then packages that stream into a common video container after the transfer is complete.

To compare the pros/cons of these two approaches: When you are capturing frames off the deck, there's a chance the technical characteristics change during the playback, like having the aspect ratio change from 4:3 to 16:9. 

As an example taken from one of our workshop participants: With specific recordings, the content would switch from 2-channel to 4-channel in the middle of the tape. If you tried to capture that in Apple Final Cut Pro, it would cut at this point. With the DVRescue approach, when an archivist wants to get all of the media off of the tape, that is possible. Then, the archivist can sort out the media later. This allows the entire content to be captured and then cut if necessary later, rather than an archivist having to constantly monitor the transfer station to ensure each clip does not stop the transfer from happening.

Video containers that have been commonly used to wrap DV, such as MXF, Quicktime (MOV),  and Matroska (MKV), all have problems with key technical characteristics being variable.

These are some examples of variable technical characteristics:

Aspect ratio

Audio channel count

Interlacement settings

Sample rate

dvpackager analyzes the entire stream and packages these components into the wrapper of the archivist's choosing.

To understand this a bit more, it helps to understand how DV works.

Another tool in the DVRescue package is dvloupe. dvloupe is for letting archivists look at a DV stream using a hexadecimal view.

Using dvloupe, we can see that DV streams are made up of 80 byte long DIF blocks. 150 of these DIF blocks make up 1 DIF sequence, and this sequence is 12,000 bytes long. In NTSC, 10 DIF sequences make up one frame. For PAL, 12 sequences make up one frame (because PAL is taller).

dvloupe color-codes what these bits are all for so that it's easier to read and decipher the results. 

There's a header row (pink), similar to a clear barrier in 16mm film, as a break. The timecode lives in the cyan-highlighted portion of the block, the subcode DIF blocks. 

The yellow section contains VAUX (video auxiliary data), which has different pieces of technical metadata like channel count or aspect ratio. Closed captioning data is stored in this VAUX section as well. DV can include captioning data directly in the stream.

The green parts are showing the raw PCM audio that is interleaved within the data. The majority of the frame is video data, in YUV. The U and V sections are very small compared to the Y because DV has really low color resolution, and the majority of the stored data is brightness.

Okay, back to dvpackager.

When taking a DV stream and putting it into a container, it is feasible to put the DV directly into the container as it is. But generally, containers don't like to handle data for more than one purpose, so they want to handle everything as video even when DV as a stream is managing different roles at once (e.g. video, audio, captions). When DV comes from tape, it ends up being damaged or inconsistent, so you are having your player try to guess what the technical characteristics are from the first frame.

Putting DV into a container can make it more resilient, when these properties can be mapped over successfully. dvpackager will move the video components into the video stream, and move the other parts of the stream into their own streams in the container, like audio, metadata, captions, chapters, or error information.

One of the internal aspects of the DVRescue project is how we generate structured data, which is stored in XML. Running a DV file with technical characteristics that change several times, the output will be represented by <frames> elements including those characteristics, and report the first and last frame of the sequence, and any frames that contain unusual events like errors or timecode jumps.

As we've seen here, dvpackager can package DV streams into an archivist-determined wrapper, but it can also "unpackage" the file back out into a DV stream, making the process reversible. This is not guaranteed, though, and there are some exceptions when this won't work:

When capturing DV and you unplug your computer in the middle, and the last frame is not a full frame, the partial frame will be filled in at the end

Presentation time can be difficult to map back and forth with two different timebases

There are potentially other edge cases as well when the process will not be 100% reversible (and verifiable through checksums), so it is not a guarantee.

DVRescue is available to download and test on all major operating systems through MediaArea. We encourage all testing feedback, errors, and issues to be filed on our GitHub Issue tracker.

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Full Interview with Elmer Dixon

Click on the link below to view the full length version of MIPoPS Program Director/Audivisual Archivist, Libby Hopfauf interviewing Black Panthers Seattle Chapter co-founder, Elmer Dixon.

https://drive.google.com/file/d/1pyjWDUqPSMhq-Mq_7g5lK3gnwt1FuMuS/view?usp=sharing

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Exciting news for those in the Venn diagram overlap of grunge fans and video format fiends: there is now a rock doc cut together almost entirely from Hi8 tapes! Shannon Hoon of Blind Melon documented his rise to fame with a Hi8 camcorder, and the tapes form the backbone of this doc, now screening online through July 31 via our long-time collaborator and exhibitor Northwest Film Forum.

Be forewarned: it is tragic. Hoon’s gradual shutdown from the vertigo of too-much-fame-too-fast is “...uncomfortable, heartbreaking, and at times chilling...” (Rolling Stone) but the impression that Blind Melon’s music left and the editorial brilliance of this tape-tapestry will keep you enthralled in spite of the lump in your throat.

Click here to learn more about our archival magnetic media screening series at Northwest Film Forum, Virtual Moving History.

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Social Distancing Video Festival - Night 4

This evening's SOCIAL DISTANCING entertainment comes to you from Hannah Palin, who is a beloved and indispensable member of MIPoPS' leadership team. Her selection for tonight takes us outdoors, in a film by Ruth and Louis Kirk, where we visit the Makah tribe to learn about the past and future of their tribal salmon management programs. The video is available on our Internet Archive collection for a limited time; please visit: https://archive.org/details/1000kirkheritageofthesea1

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Social Distancing Video Festival - Night 3

🎵On the third night of Social Distancing, Kyle Smith gave to MIPoPS... 🎵an excellent selection from our August 2018 Moving History screening. This incredible piece put together by Libby Hopfauf-Fisher really speaks for itself. She used beautiful 1-Inch Type C from a 1963 trip to the Yukon, paired with sparse and atmospheric music. Enjoy the trip!

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Social Distancing Video Festival - Night 2

Our second installment of our Social Distancing Video Festival comes to you from MIPoPS Program Manager and AV Archivist Libby Hopfauf-Fisher:

"The beloved talking fire hydrant, Big Red is featured in four educational productions created and animated by the Seattle Fire Department in the 1980s. They all tie as my favorite films Seattle Municipal Archives moving image collections. Each are equal parts bizarre, awkward, enduring and hilarious. I LOVE BIG RED!"

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MIPoPS SOCIAL DISTANCING VIDEO FESTIVAL!

Can't go out to the movies tonight? NO PROBLEM! MIPoPS was inspired by the Appalachian Media Institute to create a mini SOCIAL DISTANCING video festival! Please join us each evening at 6 pm (PST), here and on our Facebook, while we share some video material that'll transport you out of your house and out of your head. These pieces will make you laugh, they'll make you cry, and they might even make you forget the wild and crazy times we're experiencing.

"The first selection for our impromptu Video Festival is a piece from one of our Moving History screenings. Peter Minshall is a legendary Trinidadian costume designer. He has been designing incredible costumes and choreographies for Carnival celebrations for over thirty years. In August 1985, he held The Adoration of Hiroshima in Washington, D.C. This was a carnival-style, anti-war,  street theatre which was performed on the fortieth anniversary of the bombing of Hiroshima. The video footage comes from a tape in the Karen Morell Film, Audio and Videotape Collection at the University of Washington. Unfortunately, the material was silent, so we have included audio from a 1989 interview with Minshall.

I chose this video because I feel like it represents an element of the fear that so many of us are dealing with right now. Being isolated at home, in order to protect our own safety and the safety of others, we are forced to consider our mortality in a more present way than we may usually. It's scary. It's wild. It's unpredictable. We can't look away and we also can't keep looking. Also, music helps. Enjoy!" - Ari, Assistant AV Archivist @ MIPoPS

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MIPoPS & RiceCapades present [drum roll, please] the official dvrescue logo!

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dvrescue: dvpackager

Background

Software design for tools that transfer DV from tape to file take one of two approaches:

Receives all the DV frames and writes them to disk as a DV stream.

The software receives a series of DV frames, analyzes them to understand their significant properties, and wraps those frames within a container format, such as mov.

Tools such as DVHSCap, Live Capture Plus, and dvgrab use the first method. The resulting frames are stored as a stream of DV frames. The result is very authentic to what was transmitted; however, there can be significant challenges to using this data. DV supports a variety of options within several characteristics. 

Context

Consider this scenario. A cameraperson recording an interview with a musician on MiniDV tape. The interviewee is frameds in a 4/3 aspect ratio and the audio is recorded onto two channels of audio with a 4/3 aspect ratio. During the recording, the cameraperson remembers that the interview is for a production with a 16/9 production, so adjusts the camera's settings and does a second take at 16/9. Following the interview, the cameraperson records a performance by the musician's band and adjusts the camera to record 4 channels of audio rather than 2 in order to capture more of the microphones. This DV tape could be transferred over FireWire to a single, continuous DV stream; however, the resulting DV file would have a variable aspect ratio, a variable sampling rate for the audio, and variable audio channel count. Some players could support some of these changes, for example VLC will adjust the framing as aspect ratio changes though QuickTime won't. The presentation will be inconsistent since the extent of this sort of variability is rarely supported.

Tools such as Final Cut Pro 7 use the second approach. The resulting QuickTime file contains the same DV frames that first method would result in, but stores them in a convenient container. However, when the incoming DV frames contain incoherency in the characteristics, either because the camera settings changed or the data is damaged, the software will generally stop the data transfer at those events. Software that was written to expect perfect DV frames may then start to break up a DV transmission into dozens of individual files with intermittent gaps or simply stop and give error messages.

dvrescue

In order to effectively preserve DV materials in a way that scales, we need to ensure that we can transfer all of the DV data in a manner that is verifiable and also produce audiovisual files that are well-described and interoperable. This requires a mix of the two approaches above. In the design of dvrescue, we use the first approach and initially just write all incoming DVdv streams into a file. This file is intended to be a digital copy of the data stream that the DV tape player produces and contains audio, video, camera metadata, metadata about frame characteristics and information on how well the reading of the tape went. After writing those DV frames to a file, we then analyze it with the dvrescue utility and produce a report on every incoherency in the file: including jumps in timecode, jumps in recording timestamps, or changes in properties like aspect ratio or audio channel count. With that resulting data, a subsequent script, called dvpackager, then uses that report and the original DV file, to selectively encapsulate every frame into an audiovisual container such as QuickTime or Matroska. There are options here, so a user could make one file for every time the camera had the start button hit (since all the recording metadata is preserved within the DV frames) or the DV frames could be divided only by changes in properties like aspect ratio or channel count.

The need for this sort of packaging is demonstrated by a recent example file shared with us by Morgan Morel at BAVC. Morgan transferred the DV data from a tape to a file using DVHSCap, which follows the most approach described above, writing the received DV frames into a file and that's about it. In QuickTime X, the file starts with about a second of grey frames and then cuts to a recording of an art installation. Some fan noise is heard in the background, but the audio is very choppy, like a mixture of noise and silence and the result is jarring to listen to. VLC creates a similar jarring presentation, where the video looks right, but the audio is painful.

This is a presentation of how QuickTime X decodes the audio of this DV stream. Wanna listen?

With dvrescue, we can figure out what is happening. The dvrescue utility will read the DV file and document events and changes that happen throughout the file.

Here we can see that at the beginning of the file, there are 19 frames that use a sampling rate of 48000 Hz, but then the subsequent frames use a sampling rate of 32000. The 19 frames at the beginning are the gray frames mentioned earlier, whereas the rest of the tape is a recording of an art installation. So QuickTime X is looking at those first frames and presuming that it's all at 48000 Hz, but then when it is decoding a DV frame that only has 32000 Hz of audio per second, that only fills ⅔ of a second, thus these large seconds of silence are interleave since the decode expects a certain number of audio samples per second, but isn't getting it.

For cases like this, we are working on a utility called dvpackager. It analyzes the stream to createget XML like (shown above) and then decides if and how to break that DV file into pieces to avoid the presentation issues that Morgan found.

After dvpackager does it's thing, we have two video files. One is very brief, just those gray frames and 48000 Hz audio. And then the recording of the art installation at 32000 Hz. When we unsplice these very different recordings from one another and handle them individually they both play well with their own unique characteristics. This approach uses the best of the two described above. We know that we got all the data, but by analyzing it and encapsulating all frames in the right way, we have content that is accessible, well-described, and ready to be sustained as digital files.

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dvrescue: dvplay

Exciting new developments are underway for the DV Rescue project. Most recently, the quality control analyzer component “dvplay” is in the beta stages of testing. dvplay is a quality control player that supports visualization of uncorrected DV data, including categorizing DV transfer errors, illuminating when selective re-transfer may be most likely to offer improvements, and providing a method to easily distinguish authentic DV data from error concealment techniques and unconcealed damage. Currently, dvplay consists of three modes:

dvplay

A frame-by-frame playback of the video file created from a DV tape transfer. Artifacts are highlighted in yellow.

dvplay -x

Screenshot from QuickTime of same frame

JPEG created in dvplay -x mode

This mode runs a check on the video for frames containing artifacts. Each frame where an artifact was detected is saved (in the same directory as the video) with the damaged pixels highlighted in yellow as a JPEG with the timecode printed on the side of the image. The images can then be reviewed to determine if recapture is necessary and possible issues in the files (such as dropouts, headclog, transfer artifacts, camcorder recording artifacts, etc.)

dvplay -m

This mode alternatively highlights all normal video images in yellow and leaves the artifacts unmasked for review.

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Call For Submissions for 2020 Screening Night!

CALL FOR SUBMISSIONS

MIPoPS will host the second annual Archival Screening Night this year at the Western Archivists Meeting in San Francisco, California. Please join us for an evening of entertainment and awareness for archival moving images, with a screening of film and video recordings from archival collections.

The event will be held at the conference hotel on the evening of Friday, April 24, from 8:30–10:00pm.

Featured archive: California Revealed.

JOURNEY WEST: THE IMMIGRANT STORY

The theme of the screening is “Journey West: The Immigrant Story.” Inspired by the conference themes of Labor, Power, and Privilege, we seek content covering diverse perspectives of the immigrant experience.  

Videotaped oral histories, news footage, music, experimental, documentary, and just about any other kind of moving images will be accepted, but submissions relating to the theme or that have a local or regional focus will be prioritized.

SUBMISSION DEADLINE: March 11, 2020

SUBMISSION REQUIREMENTS

Duration: Submissions should be no longer than 3-5 minutes. Multiple submissions are encouraged.

Metadata: Please complete the online form to submit content from your institution for consideration. Submissions must include the following details:

Your name

The name of your institution as it should appear in the program

The title of each piece

The creator(s)

The year of creation/copyright/publication of each piece

The original format

A short description of each piece (2 to 3 sentences max.)

Format: Submissions must be available in a digital format that is suitable for projection or playback over a sound system. Both digitized or born-digital content is accepted. A low-resolution version is preferred for submission in order to review and plan the programming, but plan to send us a high-res version for the night of the screening.

Preferred specs for video files: Apple ProRes 422, 24-bit audio (not HQ). 1920x1080 - if the recording is not 16x9, please add equal amounts of black on either side of the image to get to this image size.

Rights: The event will be free and open to the public. The contributing archive must have the rights or permission of the rights holder(s) to present the material and is responsible for confirming those rights. MIPoPS will delete or return all copies of materials provided following the event per the request of the contributing archive. MIPoPS will claim no rights or ownership over any material or use it for any purposes outside of projection at this one-time event.

How to Submit

Please complete the online form to submit content from your institution for consideration. You will be required to include a link to your video via a public or private online platform. Submissions will be accepted until March 11, 2020. Notifications of acceptance/rejection will be sent by March 23, 2020.

CONTACT US!

Questions can be directed to Libby Hopfauf at libby@mipops.org

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MIPoPS 2019 in Review!!!

It’s been a busy year for us at MIPoPS! From working with new partners, to beginning new projects, conferences, screenings, and everything in between - we’ve had a full, lively year! We couldn’t possibly list everything, but we’d like to share some highlights of our 2019 (in no particular order)!

We were able to get our LTO operations working smoothly, after weeks of troubleshooting!

We participated in a very cool event called NAER VAER at the Nordic Museum, with our friends Postcard From the Badland!

Libby was part of a piece by the Seattle Channel that featured MIPoPS and the work we’ve done with the Southwest Seattle Historical Society’s Log House Museum (with our long time volunteer Jen Zook!)

We presented at the Northwest Archivists Conference in Bozeman, Montana!

We had a great screening with the Seattle Art Museum during the summer! Thanks Traci and Marie!!

Tasia, at the Log House Museum, got excited about one of our Moving History screenings!

Speaking of screenings, we had a BUNCH this year!

We SOLD OUT the theater for a screening we did in collaboration with Jill Friedberg, steward of the archives of the Independent Media Center collection. These tapes document the incredible story of Seattle’s WTO protests. This screening celebrated the 20th anniversary of the event!

Libby and her husband looking sharp before a screening!!

We made some big progress on DV Rescue and presented on it at AMIA 2019 in beautiful Baltimore, thanks to the help of Dave Rice, Ashley Blewer, and Andrew Weaver!

MIPoPS’ archivist-at-large Andrew Weaver takes 3rd place in trivia, but first place in our hearts!

We hosted our first Best Practices Day, as part of an NHPRC grant. This one was on digital preservation and we had 30 attendees!!!

Paul Sieple from the Northwest Film Forum helped MIPoPS tear down and load up a ton of equipment from a local auction! We love Paul and couldn’t do what we do without his help!!

Steve Straney and Jeff Hindle made an awesome promo for MIPoPS this year and we are OBSESSED with it!

Jill Friedberg and Libby working on protecting our moving image history!

Sometimes you work so closely that you become twins! Long time volunteer Jen Zook stole my look. Or did I steal hers? Some questions will never be answered.

And, for our final act, here are some random pictures we’ve snapped during 2019:

We can’t wait to see what 2020 has in store! - The MIPoPS Team