QRcode optical recognition in the browser - browser

What is the state-of-the-art for implementing a fully browser-based application that recognizes QRcodes in sight of the machine's webcam?
I understand that native browser support of webcams in general is still in its infancy. Have there been notable successes in processing webcam video in the browser?
In particular, is it "technically possible" given current HTML5 technologies to actually get the data of a QRcode from a live webcam image in the browser, WITHOUT making any trips to the server for image processing?

You can do this in Flex/Actionscript with zxing. See here: http://code.google.com/p/zxing/source/browse/trunk#trunk%2Factionscript

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How to play live audio stream using Google Actions Dialogflow

I have been trying to find a way to play live stream of audio (mp3) using Google Actions but haven't found a way to do so.
I tried Media Response as well but as mentioned in the documentation it doesn't support live stream.
I followed this thread but it doesn't have any examples to help me with.
Is it possible to play live mp3 stream using Google Actions?
I've had relatively good results with the Media Player being able to handle mp3 "streams". There are a couple of problems doing this, however:
There is a time limit on the audio playback (4 hours last time I checked, but it may have changed).
There isn't any such thing as an mp3 "stream". The player treats it as a single mp3 file that it downloads in chunks using HTTP headers, unlike some of the streaming protocols that allow for varying bitrate based on network and other conditions.
If this is an issue, one alternative might be to use the Interactive Canvas (which uses Chrome on the device) to present an HTML page that has an <audio> tag in it that you control. This gives you a little more control (most streaming protocols are either supported or have JavaScript libraries that can do the work), but there are some downsides:
This will only work on Smart Displays and Android. Smart Speakers aren't supported.
Interactive Canvas is only allowed for certain types of Actions. Currently it must be a game, a story, or an educational Action.

What libraries/APIs allow me access real time audio waveforms of a phone call?

I am looking to build an app that needs to process incoming audio on a phone call in real time.
WebRTC allows for this but i think this works only in their browser based P2P audio communications functionality but not for phone calls/ VOIP.
Twilio and Plivo allow you record the audio for batch/later processing.
Is there a library that will give me access to the audio streams in real time? If not, what would I need to build such a service from scratch?
Thanks
If you are open to using a media server (so that the call is not longe P2P but it's mediated by the media server using a B2B model), then perhaps the Kurento Media Server may solve your problem. Kurento Media Server makes possible to create processing capabilities which are applyied in real time onto the media streams. There are many examples in the documentation of computer vision and augmented reality algorithms applied in real time over the video streams. I've never seen an only-audio processing module, but it should be simple to implement just by creating an additional module, which is not too complex if you have some knowledge about C/C++ and media processing concepts.
Disclaimer: I'm part of the Kurento development team.

If I can't use WebRTC, what can I use right now for live streaming video

I'm working on a web app in node.js to allow clients to view a live streaming video via a unique url that another client will broadcast from their webcam, i.e., http://myapp.com/thevideo
I understand that webRTC is still not supported in enough browsers to be useful.
I would also like to save this the video stream to be viewed later within the app.
Things get somewhat confusing as I try to narrow down a solution to make this work.
I would like to get some recommendations on proven solutions out there to make this work on desktop and mobile? Any hints would be great.
I'll make a quick suggestion based on the limited details. I would use ffmpeg to encode to HLS. This format will playback natively on iOS and safari on Mac. For all other platforms, either provide an rtmp stream with a flash front end, or use jw player 6 commercial version that can play HLS. Or use a wowza server to handle this all for you.

haxe/flash: Capture webcam to disc with node.js - possible?

I know I could resolve the problem easily with Red5 Media Server. I'm just curious, since I need a node server anyway and wondered if I can bypass Red5. Using the HTML5 camera api is not an option since I target up to four cameras at the same time.
I didn't see anything specific for Node.js to work with webcams. However, I saw this solution online which uses JavaScript, NodeJs, HTML5 (canvas) and WebSockets mainly to achieve frames out of video streaming then it uses the websockets to transfer the image into HTML5 canvas using NodeJs as an intermediary server.
hope it helps.
I'm the author of https://www.npmjs.com/package/camera-capture which supports portable easy to use API for node.js (server side) to capture camera video, audio and even desktop. Doesn't require any native libraries / dependencies and is easy to install - based on puppeteer. I'm already using it on desktop apps based on gtk, cairo, qt, and others and it's behaving acceptably fast although I keep looking for optimizations since the project it's pretty new. Feedback is most welcome.

Flash + RTMFP + Stratus: Video Quality on Linux

I'm developing a video chat-like application using Flash RTMFP and Stratus. So far, I'm having good success. I can build from source, tweak settings, and get video and audio in both directions.
There's one glaring problem I haven't been able to solve, however -- when using a client on a Linux machine, the video received by the other end looks very poor. It's blocky and pixellated, almost as if it's rendering 160x120 in a much larger frame. When sending from a Mac (my other dev machine), the video looks quite good.
I've tried modifying all the settings I can think of -- frame rate, "quality", size, audio settings -- with no discernible improvement. I've tried running it as a local file and from a remote server. The network where I'm working is extremely fast, so that shouldn't be an issue.
Is there anything else I can try? Any suggestions or ideas are greatly appreciated.
Many thanks!
Bad camera or bad camera driver?
Stratus does not change video encoding, it simply is another variation of the RTMFP protocol for transferring exactly the same compressed stream.
One way you can check whether Stratus indeed plays any role in this is to try to stream the same stuff through Adobe Flash Media Server, the development version is free from adobe.com.
I have done Stratus applications, and have not experienced any degradation of video quality compared to Flash Media Server solution. In fact when the camera quality is set to 100, you won't notice the difference between raw camera video and compressed stream when using loopback mode. Apart from possibly limited framerate, if you specify bandwidth (the three are intimately related - bandwidth, framerate, quality, as per documentation of Camera.setQuality or Camera.setMode)

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