Deltachat-android: video recording

[r10s]

we should consider bringing video recording to delta-dev (it is there in the current tg/f-droid verison).

while recording as such is very simple (only an activity), the harder part is the recoding - resulting files should not be larger than dcContext.getConfig("sys.msgsize_max_recommended") bytes (about 17 mb or so).

the telegram-ui recoded using ffmpeg c-lib, however, i think we should try doing this with a java-lib first, maybe exoplayer can also recode.
EDIT: in any case, it also makes sense to update the exoplayer at a given time, eg. signal updated to 2.8.4 at https://github.com/signalapp/Signal-Android/commit/db9bfb4b2fa5be22416ff959533ea677fe5dae49

finally, it would be really nice to get the cut-video-activity from the telegram-version :)

[r10s]

just dived a bit into the old source code:

1. the activity for recording is the system one, we can just use that (although, additionally, it would be cool to record a video by _holding_ the trigger-button in the quick-camera view)
2. the activity VideoEditorActivity is used for setting cutting marks on android, it is Java-only-code (already reworked by me some time ago :), i think huger parts of this activity can be reused (in general, it would be cool to have the video "staged" as photos and having the same "edit" button on the thumbnail preview)
3. for recoding, telegram-delta uses the ffmpeg-c-library, libyuv and belonging dependencies. it would be nice if this is not needed.
   however, the only call to jni i've seen is Utilities.convertVideoFrame() which is used only as a fallback for SDK<18.

i think if SDK<18 cannot record videos, this would be a good compromise as this would save us lots of additional dependencies. note, that there is already an issue requesting SDK 19 as minimum, #437

[angelo-fuchs]

wrt min sdk: We can also disable features if the older SDK doesn't support them. (So users on old phones would get a DeltaChat that has all the features their phones can do, but "fancy" stuff is only for more current phones)

[r10s]

wrt min sdk: We can also disable features if the older SDK doesn't support them.

yip, i also think, this would be fine. video reocording only for api 19 or whatever is needed to make this possible with reasonable effort.

[cyBerta]

The repository was moved and VideoEditorActivity can be found here

[r10s]

@cyBerta iirc it will take some time until the work on this will start from you site. to not block the issue until then, i've unassigned you for now. feel free to reassign when work on this has really started.

[r10s]

closed by #883 :)