I've been wanting to build a hackday project that takes images captured from our satellites and builds a video stream. (we gets hundreds of new shots from space every minute, for fun create a screensaver-like streaming video feed of interesting pictures)

perhaps I can build it with either ffmpeg or pion (using pkg/driver/screen as a model to create a virtual canvas to draw on)

A universal translator framework cannot provide a bespoke translation engine for all possible permutations of source and target language. Instead it provides a common engine which is meant to be suitable enough for the most common traits shared across languages.

When converting any two languages at random, there will be quirks of the language or errors/ambiguity in the source prose which the engine cannot hope to all automatically recognize and accommodate, so there are all these options that do one specific thing and allow users to modify a step of the translation process. The docs cannot go in detail because the downstream ramifications of the option can vary based on the exact properties of the source-target pair and the transformations requested of ffmpeg. Instead the docs will describe the exact change directly triggered by the option.

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As for the specific options,

* -fflags +genpts, +igndts, +ignidx

All of these apply to inputs only.

genpts: if input packets have missing presentation timestamps, this option will assign the decoding timestamp as PTS, if present.

igndts will unset dts if packet's pts is set.

ignidx is only applied to a few formats. These provide a keyframe index, which ffmpeg uses to populate its internal KF index for the stream. This option makes ffmpeg ignore the supplied index.

* -vsync

The option is misnamed. It's better called fpsmode. Most commonly used to drop or duplicate frames to achieve a constant framerate stream.

* -copyts

FFmpeg will, by default, remove any starting offset to input timestamps or adjust timestamps if they overflow (roll over) or have a large gap. copyts stops all that and relays input timestamps. Basically used if one wishes to manually examine and adjust timestamps using setpts filter or setts bitstream filter.

* -use_wallclock_as_timestamps 1

Discards input timestamps and assign system clock time at time of handling packet as its pts.

https://github.com/skorokithakis/catt

You might need a VPN as whatever is running catt must be able to connect to your chromecast and chromecast must be able to pull from whatever is running catt.

We watch all the movies this way - just cast an mp4 file. Works great on a local network.

Both let you stream their videos to Chromecast last I checked.

Plex also has support for pictures which might be interesting in some related cases

You can however go the way described in the post: instead of requesting data though the data channel, you can initiate video/audio channels and make your streaming work pretty much like google hangouts, having your streamer as a participant.

It is not the recommended way though. But no other way for iOs anyways.

I came across your post[0] about KVS from a while ago. Thank you for your work on pion and KVS.

A quick question on the KVS, C implementation. Is this in anyway tied to be used with AWS Kinesis? Can it be used with Wowza for instance?

[0] https://news.ycombinator.com/item?id=21951692

Or https://github.com/pion/webrtc/tree/master/examples/save-to-...