bigbluebutton/bbb-presentation-video

Script to render a video of the presentation area from a BBB recording events.xml

BigBlueButton

BigBlueButton is an open-source virtual classroom designed to help teachers teach and learners learn.

BigBlueButton supports real-time sharing of audio, video, slides (with whiteboard annotations), chat, and the screen. Instructors can engage remote students with polling, emojis, multi-user whiteboards, shared notes, and breakout rooms. During the session, BigBlueButton generates analytics that are visible to moderators in the Learning Analytics Dashboard.

Presenters can record and playback content for later sharing with others.

We designed BigBlueButton for online learning, it can be used for many other applications as well. The educational use cases for BigBlueButton are

• Online tutoring (one-to-one)
• Flipped classrooms (recording content ahead of your session)
• Group collaboration (many-to-many)
• Online classes (one-to-many)

The latest version is BigBlueButton 2.7. You can install BigBlueButton 2.7 on Ubuntu 20.04 using bbb-install.sh within 30 minutes (or your money back 😉).

For full technical documentation of BigBlueButton -- including architecture, features, API, and GreenLight (the default front-end) -- see https://docs.bigbluebutton.org/.

BigBlueButton and the BigBlueButton Logo are trademarks of BigBlueButton Inc.

bbb-presentation-video's Issues

math domain error in perimeter_of_ellipse

An error calculating the perimeter of an ellipse is causing recording processing to fail.

A shape that is triggering this problem:

  	Tldraw: added shape: XXXX, presentation: XXXX, slide: 0, EllipseShape(style=Style(color=<ColorStyle.BLACK: 'black'>, size=<SizeStyle.SMALL: 'small'>, dash=<DashStyle.DRAW: 'draw'>, isFilled=False, scale=1, font=<FontStyle.SCRIPT: 'script'>, textAlign=<AlignStyle.START: 'start'>), childIndex=1, point=Position(x=257.09, y=742.34), rotation=0, label=None, labelPoint=Position(x=0.5, y=0.5), radius=(18.973415910471772, 2.08882555115963), size=Size(width=37.946831820943544, height=4.17765110231926))

And the resulting crash:

Traceback (most recent call last):
  File "/usr/bin/bbb-presentation-video", line 11, in <module>
	load_entry_point('bbb-presentation-video==4.0.2', 'console_scripts', 'bbb-presentation-video')()
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/__init__.py", line 164, in main
	renderer.render()
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/__init__.py", line 299, in render
	tldraw_changed = tldraw.finalize_frame(presentation.transform)
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/__init__.py", line 236, in finalize_frame
	finalize_ellipse(ctx, id, shape)
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/ellipse.py", line 163, in finalize_ellipse
	draw_ellipse(ctx, id, shape)
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/ellipse.py", line 81, in draw_ellipse
	stroke_points, perimeter = draw_stroke_points(id, radius, style)
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/ellipse.py", line 42, in draw_stroke_points
perimeter = perimeter_of_ellipse(rx, ry)
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/utils.py", line 185, in perimeter_of_ellipse
	return pi * (rx + ry) * (1 + (3 * h) / (10 + sqrt(4 - 3 * h)))
ValueError: math domain error

The cause appears to be that the randomness applied in

bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/ellipse.py

Lines 40 to 41 in f9f3ae6

	rx = radius[0] + random.uniform(-variation, variation)
	ry = radius[1] + random.uniform(-variation, variation)

is sufficient to make the calculated value of h in

bbb-presentation-video/bbb_presentation_video/renderer/tldraw/utils.py

Lines 184 to 185 in f9f3ae6

	h = (rx - ry) ** 2 / (rx + ry) ** 2
	return pi * (rx + ry) * (1 + (3 * h) / (10 + sqrt(4 - 3 * h)))

evaluate to a value which causes the argument to the sqrt function to be negative.

It looks like this is possible when one of the ellipse radiuses is smaller than the stroke width.

Given that this code is based directly on tldraw upstream code, the problem might also exist there. (Due to the different random number generation method used, it won't happen on the same shape.)

Reduce the max size of the tldraw canvas

Following bigbluebutton/bigbluebutton#17086

In order to improve readability of the whiteboard, let's reduce the max size of the [canvas] page to maxImageWidth = 1440; maxImageHeight=1080

The merges need to be synchronized so that they all target the same BBB release.

Rendering of BigBlueButton 2.5 and earlier whiteboard is blank

Some sort of mistake was made in the tldraw work that prevents the classic BigBlueButton whiteboard from being rendered - a blank white area is shown instead. Need to investigate this issue and fix it; the code to support the classic whiteboard is still present and used to work.

Why video player is needed to play video and public chat entries?

Hi all.
Recently I installed bbb-playback-video and cannot obtain an only mp4 file. The video link opens a page with a player which plays back video from webcams and screenshare but not the whiteboard or pdf presentation uploaded nor public chat entries.
The public chat entries are only able to view them with the visor webpage.
Is there any way to obtain just a mp4 file with webcams, audio, whiteboard with annotations or presentation uploaded, and public chat entries?
As reference, something like Daniel Petri's project did on BBB 2.3 to 2.5 versions.
(https://github.com/danielpetri1/bbb-recording-exporter)
Thanks in advance.
JP

Error when rendering label of some shapes

  File "/home/bigbluebutton/dev/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/rectangle.py", line 190, in finalize_rectangle
    finalize_label(ctx, shape)
  File "/home/bigbluebutton/dev/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/text.py", line 205, in finalize_label
    return (label_size, scale_adj)
UnboundLocalError: local variable 'scale_adj' referenced before assignment

Label error: Missing scale_adj variable definition when scale is none (other than arrow shape labels I think)
https://github.com/bigbluebutton/bbb-presentation-video/blob/main/bbb_presentation_video/renderer/tldraw/shape/text.py#L182

Implement sticky notes

Tldraw sticky notes from the live meeting are not replayed in the video yet

Update slide scaling to match BBB

bigbluebutton/bigbluebutton#16721 changed BigBlueButton's handling of slide images to scale the slide to fit in a fixed rectangle, and use the scaled size for the size of the tldraw whiteboard. The scaling of shapes in this tool has to be adapted to match.

For reference, the values used in the BBB change can be seen here: https://github.com/bigbluebutton/bigbluebutton/pull/16721/files#diff-526fb6e01c328202327197d3a09f894ccab6fab82f364da75c846a4b358b1814

Missing arrow line when there is more than one Arrow Shape with Label

Only the first arrow shape of the page is draw correctly with an Label, the other ones are "invisible" and just the label is shown

Implement arrow shapes

Tldraw arrow shapes from the live meeting are not replayed in the video yet

cairo.Error: invalid matrix (not invertible) on small ellipse

Hit an error when drawing ellipses in some cases which breaks recording processing:

01520.837000 tldraw.add_shape
  	Tldraw: added shape: XXX, presentation: XXX, slide: 3, EllipseShape(style=Style(color=<ColorStyle.BLACK: 'black'>, size=<SizeStyle.SMALL: 'small'>, dash=<DashStyle.SOLID: 'solid'>, isFilled=False, scale=1, font=<FontStyle.SCRIPT: 'script'>, textAlign=<AlignStyle.START: 'start'>), childIndex=0, point=Position(x=140.06, y=276.97), rotation=0, label=None, labelPoint=Position(x=0.5, y=0.5), radius=(1.2269886363636573, 2.656534090909105), size=Size(width=2.4539772727273146, height=5.31306818181821))
 	Tldraw: Rendering 1 shapes.
  	Tldraw: Finalizing Ellipse: XXX
Traceback (most recent call last):
  File "/usr/bin/bbb-presentation-video", line 11, in <module>
load_entry_point('bbb-presentation-video==4.0.2', 'console_scripts', 'bbb-presentation-video')()
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/__init__.py", line 164, in main
	renderer.render()
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/__init__.py", line 299, in render
	tldraw_changed = tldraw.finalize_frame(presentation.transform)
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/__init__.py", line 236, in finalize_frame
	finalize_ellipse(ctx, id, shape)
 File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/ellipse.py", line 165, in finalize_ellipse
	dash_ellipse(ctx, shape)
  File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/ellipse.py", line 135, in dash_ellipse
	ctx.scale(rx, ry)
cairo.Error: invalid matrix (not invertible)

Probably need to switch the code to draw a bezier approximation to an ellipse instead of using cairo's ellipse function, like was done on the older BBB whiteboard.

Triangle shape from BigBlueButton <= 2.5 doesn't parse correctly.

When running bbb-presentation-video over a 2.5 recording, triangle shapes aren't parsed correctly. The log contains:

Failed to parse event AddShapeEvent: Unknown shape 'triangle'

2.6.0 recording fails video format in tldraw POINT

fails in processing stage.

I, [2023-03-24T20:32:05.715077 #6515]  INFO -- : 00045.015000 tldraw.add_shape
I, [2023-03-24T20:32:05.870626 #6515]  INFO -- : Traceback (most recent call last):
I, [2023-03-24T20:32:05.870694 #6515]  INFO -- :   File "/usr/bin/bbb-presentation-video", line 11, in <module>
I, [2023-03-24T20:32:05.870704 #6515]  INFO -- :     load_entry_point('bbb-presentation-video==4.0.0rc2', 'console_scripts', 'bbb-presentation-video')()
I, [2023-03-24T20:32:05.870714 #6515]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/__init__.py", line 165, in main
I, [2023-03-24T20:32:05.870722 #6515]  INFO -- :     renderer.render()
I, [2023-03-24T20:32:05.870731 #6515]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/__init__.py", line 257, in render
I, [2023-03-24T20:32:05.870740 #6515]  INFO -- :     tldraw.update(event)
I, [2023-03-24T20:32:05.870748 #6515]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/__init__.py", line 190, in update
I, [2023-03-24T20:32:05.870758 #6515]  INFO -- :     self.add_shape_event(cast(tldraw.AddShapeEvent, event))
I, [2023-03-24T20:32:05.870766 #6515]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/__init__.py", line 145, in add_shape_event
I, [2023-03-24T20:32:05.870774 #6515]  INFO -- :     shape.update_from_data(data)
I, [2023-03-24T20:32:05.870781 #6515]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/__init__.py", line 231, in update_from_data
I, [2023-03-24T20:32:05.870789 #6515]  INFO -- :     self.handles.update_from_data(data["handles"])
I, [2023-03-24T20:32:05.870796 #6515]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/tldraw/shape/__init__.py", line 198, in update_from_data
I, [2023-03-24T20:32:05.870805 #6515]  INFO -- :     self.start = Position(data["start"]["point"])
I, [2023-03-24T20:32:05.870812 #6515]  INFO -- : KeyError: 'point'
I, [2023-03-24T20:32:06.023303 #6515]  INFO -- : Success?: false
I, [2023-03-24T20:32:06.023370 #6515]  INFO -- : Process exited? true

tldraw.tar.gz

Texts/labels are always aligned left

Texts/labels are not respecting the Alignment property anymore, they are always aligned on the left

From what I saw this was introduced with the show_layout_by_lines:
https://github.com/bigbluebutton/bbb-presentation-video/blob/main/bbb_presentation_video/renderer/tldraw/shape/text.py#L95

2.6.1 video recording failed (cairo.Error: invalid value (typically too big))

2.6.1 video recording failed (cairo.Error: invalid value (typically too big))

I, [2023-04-07T10:59:15.010155 #3536697]  INFO -- :     Presentation: pan: [0.000,0.000] zoom: 0.010x0.010
I, [2023-04-07T10:59:15.010176 #3536697]  INFO -- :     Presentation: padding: 0.000x90.003
I, [2023-04-07T10:59:15.010194 #3536697]  INFO -- :     Presentation: slide size: 19.899x11.193, scale: 48.244236, position: [-0.000,-0.000]]
I, [2023-04-07T10:59:15.010214 #3536697]  INFO -- :     Presentation: slide scaled size: 960.000x539.994
I, [2023-04-07T10:59:15.010232 #3536697]  INFO -- :     Presentation: shapes size: 2048.000x1152.000, scale: 0.937500
I, [2023-04-07T10:59:15.287457 #3536697]  INFO -- : Traceback (most recent call last):
I, [2023-04-07T10:59:15.287535 #3536697]  INFO -- :   File "/usr/bin/bbb-presentation-video", line 11, in <module>
I, [2023-04-07T10:59:15.287554 #3536697]  INFO -- :     load_entry_point('bbb-presentation-video==4.0.1', 'console_scripts', 'bbb-presentation-video')()
I, [2023-04-07T10:59:15.287573 #3536697]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/__init__.py", line 164, in main
I, [2023-04-07T10:59:15.287590 #3536697]  INFO -- :     renderer.render()
I, [2023-04-07T1
[3b0d676c53d544e4437850a1fd74757e053bbca8-1680858052156-events.xml.txt]
0:59:15.287608 #3536697]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/__init__.py", line 297, in render
I, [2023-04-07T10:59:15.287625 #3536697]  INFO -- :     presentation_changed = presentation.finalize_frame()
I, [2023-04-07T10:59:15.287642 #3536697]  INFO -- :   File "/usr/share/bbb-presentation-video/bbb_presentation_video/renderer/presentation.py", line 354, in finalize_frame
I, [2023-04-07T10:59:15.287659 #3536697]  INFO -- :     pdfSurface = cairo.ImageSurface(
I, [2023-04-07T10:59:15.287676 #3536697]  INFO -- : cairo.Error: invalid value (typically too big) for the size of the input (surface, pattern, etc.)
I, [2023-04-07T10:59:15.436224 #3536697]  INFO -- : Success?: false
I, [2023-04-07T10:59:15.436308 #3536697]  INFO -- : Process exited? true
I, [2023-04-07T10:59:15.436329 #3536697]  INFO -- : Exit status: 1

events.xml attached, can provide complete raw archive if needed.
(https://github.com/bigbluebutton/bbb-presentation-video/files/11183119/3b0d676c53d544e4437850a1fd74757e053bbca8-1680858052156-events.xml.txt)

Add support for public chat

Hi everyone
once again thank you for developing this amazing software

I was wondering if there was an option to dedicate a part of the output video to the chat (like the options for deskshare and webcam and presentation, we could have a complete all in one solution for sharing the recorded session with out the need to have a host for playback (right now if we want to have chat included we have to use the play back page, which is restricting if we wanted to use some sort of external space)

thanks for your time

Line shapes are drawn with the arrow head

They are treated like an arrow shape but without the decoration