<kaz> scribenick: kaz
Chris: WoT, TPAC plans, Media Integration Guidelines, Web Codecs
Chris: A few quick updates.
There's a call for review for MediaStream Track Content Hint
... MediaStreamTrack is used in WebRTC and MediaRecorder.
... The content hints allow web app to say if the content is
expected to be speech or music (for audio), or motion or text (for
video).
... It allows the browser to configure the encoding
appropriately.
... Please take a look, file issues if you have feedback.
Chris: Also liaison letters from ITU-T SG16
Chris: The first one is an
announcement of VVC codec.
... The liaison on immersive live experiences could be a
collaboration with the Immersive Web groups.
... Before moving ahead, any other topics for today?
(none)
<cpn> scribenick: cpn
Kaz: The WoT WG are working on use
cases and have published on April 9th, possibly media related use
cases
... NHK have submitted one use case for TV synchronization using
Hybridcast. There are more possible use cases, including BBC's
grand prix video
... The WoT would like more possible use cases from the media
industry, and input on their existing proposals
... They invite you to provide your ideas. You don't need to
provide use case descriptions in detail, app software, media
streams, and devices
Chris: What's the next milestone?
Kaz: I'd like to send a request for contribution or ideas to our MEIG participants, and individually
<kaz> scribenick: kaz
Chris: happy to help
... media in home, media devices within IoT environment, etc.
... if it's part of your/your organization's business arias, please
let us know
<cpn> scribenick: cpn
Kaz: I'd like to bring any input to the WoT group
<kaz> scribenick: kaz
<inserted> scribenick: kaz
Chris: TPAC is a virtual meeting this
time.
... Overall plan is Oct 12-16 for joint meetings and Oct 26-30 for
breakouts.
... Our IG would like to have a joint meeting with TTWG and Media
WG
... to cover text tracks in MSE, Text Track CUE API.
... We'd like to cover DataCue too.
Nigel: Would make sense to have the
joint discussion
... TTWG produces TTML, WebVTT, IMSC as a profile for TTML.
... There's a discussion on text track cue to be had. Which group
should develop those APIs, Media WG, TTWG perhaps?
Chris: Thanks Nigel.
... The other group we want to have a joint meeting is the Color on
the Web CG.
... HDR and WCG are topics related to a bunch of groups, Media WG
for Capability detection, also CSSWG.
... There's work happening on color spaces in the Canvas API.
... We can get updates on progress, and do some cross-group
coordination.
... Also another potential meeting with WoT, depending on how
discussions proceed in the meantime.
... Any other suggestions?
Barbara: Joint meeting with Web Machine Learning Community Group - TPAC or a future monthly meeting. Topic would be reviewing their use case targets before going to a WG.
Chris: Good point, let's follow it up.
Will: Web Transport WG? We'd want to get input from media companies.
<BarbH> +1 on Transport
Will: We don't have an official date yet since the group is not yet created.
Chris: OK
... We'll make sure to send an invitation to them,
... and ensure our meetings don't overlap so people who are
interested can join both.
... For the MEIG meetings, we propose two sessions over two
days.
... Oct 19, Monday at 4pm Europe
... Oct 21, Wednesday at 7am Europe
... Different times to let Asian people join easier.
... We are planning to have discussion on CTA WAVE Web Platform
tests, a report from Fraunhofer Fokus.
... If you have any suggestions for the the agenda, please let us
know.
... It would be good to have discussion with CTA WAVE on other
topics too, e.g, Content spec, Capabilities, Web Media API.
... Olease let us know if you want to have other joint meetings as
well.
... Does the plan sound good to you? Any possible conflicts?
(none at the moment)
<cpn> scribenick: cpn
John: We discussed on a call a while
ago, but I'll recap.
... In CTA WAVE, there a discussion around interoperability pain
relating to A/V decoders,
... e.g., devices with only one decoder. How best to handle?
... The scope is to create an IG note that seeks to describe the
major browers, how to handle the APIs, discrepancies.
... We started with issues to collect info. Categorised into 3 main
topics: claiming hardware resources, resource contention,
timing.
... The first step is gathering information on how various UAs
handle the issues we've raised.
... When we have input from all browser vendors, we'll see if there
are discrepancies.
... If it makes sense to bring somethign to WICG or WHATWG to
standardize, we'll facilitate that through the IG.
... It seems likely we'll do that, there will be spec changes
needed.
... We had a call for co-editors. Franco Ghilardi from Comcast will
help, but we would welcome more co-editors.
... We have input from Google (Dan and Chris) on how Chrome handles
some of the issues.
... We're looking for additional input, we've reached out to
Mozilla, Microsoft, Apple.
... We're looking forward to their feedback. Can we use some of the
time at TPAC to get their input?
... Anyone is welcome to file additional issues. Also, if you have
input on real world experience on the issues already raised, that
would be welcome
... This would help other developers using the APIs
... Any questions?
<inserted> scribenick: kaz
Chris: We could set up a dedicated
meeting with the browser vendors,
... Do you have any time schedule for this work?
John: No specific deadline at the
moment, but it would be nice to have some discussion during
TPAC.
... Chrome Team did a great job with this.
Chris: Any other questions/comments?
(none at the moment)
Chris: Thanks for your work, John! It's a really good starting point.
Chris: In previous months we've heard
about Microsoft's client-side video editing API proposal, then Web
Codecs API. What should the MEIG do next?
... Links for previous minutes here
Chris: Web Codecs is very
powerful.
... You can use Web Codecs for decoding the media and Canvas for
rendering.
... Is there something we need to think about, e.g., client-side
video editing.
... Not sure about the status of video editing API, is this still
needed or can it maybe be implemented on top of Web Codecs?
... I would like to hear from you. Any particular views on what we
should do next?
... For example, we can gather use cases, evaluate the API against
them. Anybody interested in that activity?
... We heard Google's plan for origin trial during the previous
call.
... I'd like to do a brief walkthrough of the draft spec.
<cpn> https://docs.google.com/document/d/11n6xLkZThJkDc7SBFzUVAynl5kZsxZJtjy_BjbxE8a0/edit#
Chris: Looking at VideoDecoder interface, you initialize with a frame callback you supply.
Chris: For audio decoding, the
AudioFrame contains an AudioBuffer. AudioBuffer comes from the Web
Audio API.
... In ImageFrame, the timestamp information is optional, there's
data on the pixel format.
... A question here is how would this work with WebGPU for further
image processing,
... we'd want to avoid copying fro, GPU memory and CPU
memory.
... This was just a brief overview of the proposed WebCodecs
API.
... We had this kind of idea for media production, editing use
cased, but also realtime playback,
... e.g., a visual mixing editor.
... So the question is what should we do as the whole MEIG?
<BarbH> Webcodec are working with the WebGPU and the video_shader
John: This is useful, but I don't have any particular use cases myself, though.
Chris: I have one in mind, which is
replacing use of WebAudio decodeAudioData, which is a blocking
procedure.
... If we can use Web Codecs instead and stream the audio, we can
show progress information in the UI.
... We're potentially interested in vision mixing as well.
... I'm wondering how many of us are interested in this from a
media production point of view.
Pierre: The client-side video editing idea still on TAG's review. right?
Pierre: This could possibly be done by Web Codecs? Decoding to baseband.
Chris: Web Codecs might not be a direct replacement and possibly need both the proposed APIs
<BarbH> We are looking at Latency-sensitive live streaming. There is alignment with Web Transport
Chris: Individual companies can respond directly.
Barbara: We're looking at latency-sensitive use case, you may want to investigate that.
Chris: Yeah, coupling with Web Transport for low latency media delivery.
Barbara: Right, we're working on PoCs.
Chris: Getting feedback based on
implementation is good.
... We've covered all the topics in the agenda. The next call will
be held on Sep. 1 at the same time.
[adjourned]