Feature: realtime player

[pozitronik]

In GUI mode do a realtime player: get frames and the sound from the target, do in-memory frames swap (may be with some buffering) or any other possible operation, and play the result. Also add quality presets: to improve processing speed, frames can be shrunken before processing, and restored in size after.
Also it may be possible to enable frame drop: render as many frames as possible, and just drop any other.

• when wrong path is passed as source, gui produces an unhandled error
• GUI won't start without a provided target
• add quality control to change processing image scale on the fly. Also show last/median frame processing time
• use pygame.display to show rendered frame as fast, as possible
• implement pygame display resize stuff
• Do not resize display on input frame change, resize the frame instead
• combine with WebCam module, there's no need to multiply entities
• fix/check behavior with image target
• add a pause button to stop player only (continue background buffering) there's no need due the current design
• add frame rotation controls
• fix issue with long processing restart on position change
• move bootstrap_frames() to a background thread, to not to block program. Get frames right from target, if they are not bootstrapped.
• Remember and restore previous windows positions on the screen
• Add "stay on top" control/option
• Move frames extracting to the separate thread (make another queue). The experiment was unsuccessful: there's no profit to buffer all frames, because the next required frame index is unknown, while playing. The feature is postponed.
• fix the issue with broken frame navigation while playing
• need to try to implement new control to edit frame processors set and order
• show gui progressbar on long operations (buffering, extracting, etc)
• sound
• documentation

Known issues:

• The PygameFramePlayer may not refresh when showing frame while playing (e.g. shows two frames at same time)

[pozitronik]

This task requires #66

[pozitronik]

Done as a part of WebCam module. Now i need to implement it in the GUI module.

[pozitronik]

todo: when wrong path is passed as source, gui produces an unhandled error

[pozitronik]

todo: GUI won't start without a provided target

[pozitronik]

todo: add quality control to change processing image scale on the fly. Also show last/median frame processing time.