Various bugs with fade in/out with the VSE (Sequencer) #73056

New Issue

Nick Gammon · 2020-01-12T06:04:02+01:00

Nick Gammon commented

2020-01-12 06:04:02 +01:00

System Information
Operating system: Linux-4.15.0-39-generic-x86_64-with-debian-buster-sid 64 Bits
Graphics card: GeForce GTX 780/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 390.77

Blender Version
Broken: version: 2.82 (sub 6), branch: master, commit date: 2020-01-10 15:30, hash: 1cb938ef2c

Short description of error
Fade in/out (opacity) change fails in various ways as described below.

Exact steps for others to reproduce the error

Make a new Blender Video Editing project.
Add a Color strip and change its duration to 100 frames.
Change the colour of the colour strip to make it obvious when it fades in and out.
RH-click the strip and select Fade -> Fade In And Out
Move the playhead to frame 3. Although the opacity is supposed to be 0.020 (see properties) it is shown in the preview window at full opacity.

{F8271854, size=full}

Changing the blend mode from "Cross" (the default) to "Replace" fixes that. Changing back to "Cross", it stays fixed.
The effect seems intermittent. Re-doing the above steps, this time I have full opacity displayed at frame 1:

{F8271872, size=full}

However correct opacity at frame 2:

{F8271877, size=full}

Now if I delete the curve in the graph editor, it seems to sort-of "remember" the opacity, as it fades up and down still, however the opacity shown in the properties window remains at 0.005 for some reason. Despite what the opacity property value is, the opacity now fades up and down at the start, and occasionally flickers from full to no opacity (for example, at frame 44):

{F8271883, size=full}

Interestingly, frame 44 looks like the one frame that wasn't preloaded for some reason (see earlier screenshot) so this may be related.
If I try to recover by RH-clicking on the strip and selecting Clear Fade I get this error message:

Traceback (most recent call last):
  File "/home/nick/blender-2.82-1cb938ef2c92-linux-glibc217-x86_64/2.82/scripts/startup/bl_operators/sequencer.py", line 154, in execute
    fcurves = context.scene.animation_data.action.fcurves
AttributeError: 'NoneType' object has no attribute 'fcurves'

location: <unknown location>:-1

My guess is that there is some sort of memory caching issue here.
The issue isn't related to the Color Strip as such. I originally noticed the effect with a video sequence, however since it can be reproduced with a Color Strip, that is easier to reproduce than supplying a video file.

Thanks for any assistance!

fade in out bug.blend

**System Information** Operating system: Linux-4.15.0-39-generic-x86_64-with-debian-buster-sid 64 Bits Graphics card: GeForce GTX 780/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 390.77 **Blender Version** Broken: version: 2.82 (sub 6), branch: master, commit date: 2020-01-10 15:30, hash: `1cb938ef2c` **Short description of error** Fade in/out (opacity) change fails in various ways as described below. **Exact steps for others to reproduce the error** * Make a new Blender Video Editing project. * Add a Color strip and change its duration to 100 frames. * Change the colour of the colour strip to make it obvious when it fades in and out. * RH-click the strip and select Fade -> Fade In And Out * Move the playhead to frame 3. Although the opacity is supposed to be 0.020 (see properties) it is shown in the preview window at full opacity. {[F8271854](https://archive.blender.org/developer/F8271854/Blender_bug_-_opacity_ignored.png), size=full} * Changing the blend mode from "Cross" (the default) to "Replace" fixes that. Changing back to "Cross", it stays fixed. * The effect seems intermittent. Re-doing the above steps, this time I have full opacity displayed at frame 1: {[F8271872](https://archive.blender.org/developer/F8271872/Blender_bug_-_full_opacity_at_frame_1.png), size=full} * However correct opacity at frame 2: {[F8271877](https://archive.blender.org/developer/F8271877/Blender_bug_-_correct_opacity_at_frame_2.png), size=full} * Now if I delete the curve in the graph editor, it seems to sort-of "remember" the opacity, as it fades up and down still, however the opacity shown in the properties window remains at 0.005 for some reason. Despite what the opacity property value is, the opacity now fades up and down at the start, and occasionally flickers from full to no opacity (for example, at frame 44): {[F8271883](https://archive.blender.org/developer/F8271883/Blender_bug_-_deleted_fcurve.png), size=full} * Interestingly, frame 44 looks like the one frame that wasn't preloaded for some reason (see earlier screenshot) so this may be related. * If I try to recover by RH-clicking on the strip and selecting **Clear Fade** I get this error message: ``` Traceback (most recent call last): File "/home/nick/blender-2.82-1cb938ef2c92-linux-glibc217-x86_64/2.82/scripts/startup/bl_operators/sequencer.py", line 154, in execute fcurves = context.scene.animation_data.action.fcurves AttributeError: 'NoneType' object has no attribute 'fcurves' location: <unknown location>:-1 ``` * My guess is that there is some sort of memory caching issue here. * The issue isn't related to the Color Strip as such. I originally noticed the effect with a video sequence, however since it can be reproduced with a Color Strip, that is easier to reproduce than supplying a video file. Thanks for any assistance! [fade in out bug.blend](https://archive.blender.org/developer/F8271897/fade_in_out_bug.blend)

Nick Gammon commented

2020-01-12 06:04:02 +01:00

Added subscriber: @nickgammon

blender-admin commented

2020-01-12 06:04:02 +01:00

#75070 was marked as duplicate of this issue

blender-admin commented

2020-01-12 06:04:02 +01:00

#75039 was marked as duplicate of this issue

blender-admin commented

2020-01-12 06:04:02 +01:00

#74897 was marked as duplicate of this issue

Campbell Barton commented

2020-01-13 07:23:23 +01:00

Added subscriber: @ideasman42

Campbell Barton commented

2020-01-13 07:23:23 +01:00

Changed status from 'Needs Triage' to: 'Confirmed'

Campbell Barton commented

2020-01-13 07:23:23 +01:00

Confirmed, thanks for the detailed report.

tintwotin commented

2020-01-14 08:35:34 +01:00

Added subscribers: @GDQuest, @tintwotin

tintwotin commented

2020-01-14 08:35:34 +01:00

Tagging @GDQuest on this one though the problems may be lower level than using the API.

Nick Gammon commented

2020-01-14 21:57:13 +01:00

I am trying to track down and reproduce further problems I am having with playback of strips. My impression is that it is more of a caching issue than the specifics of the fade-in/fade-out, however as described above that is an easy way of reproducing it. I am not referring here to the proxy files, in the example above I wasn't using them.

Having said that, the Python error message if you try to Clear Fade does indeed seem to be a fade issue.

I am trying to track down and reproduce further problems I am having with playback of strips. My impression is that it is more of a caching issue than the specifics of the fade-in/fade-out, however as described above that is an easy way of reproducing it. I am not referring here to the proxy files, in the example above I wasn't using them. Having said that, the Python error message if you try to Clear Fade does indeed seem to be a fade issue.

Nathan Lovato was assigned by Campbell Barton

2020-01-15 02:10:28 +01:00

tintwotin commented

2020-01-15 06:07:09 +01:00

Removed subscriber: @tintwotin

Richard Antalik commented

2020-01-15 11:39:24 +01:00

Added subscriber: @iss

Richard Antalik commented

2020-01-15 11:39:24 +01:00

Not sure if @GDQuest would be able to take this on, in such case I will grab this

fausto m. german commented

2020-03-16 05:21:35 +01:00

Added subscriber: @nexxio

fausto m. german commented

2020-03-16 05:21:35 +01:00

I can confirm that this bug affects the audio strips too, and is more than the crossfade sound, if you add a keyframe to the volume or pitch properties it visually adds the keyframe and the curves but the animation does not work, if you put a keyframe in volume at 1, and other keyframe forward at 0 it adds the keyframes but the whole audio strip will stay with volume at 0 and if you delete the keyframes and put then again it stays the same no matter what value you put, is like if the keyframes don't work in the vse.
I tested it in the latest build -blender-2.83-f06a6e92bc5e-linux64-

I can confirm that this bug affects the audio strips too, and is more than the crossfade sound, if you add a keyframe to the volume or pitch properties it visually adds the keyframe and the curves but the animation does not work, if you put a keyframe in volume at 1, and other keyframe forward at 0 it adds the keyframes but the whole audio strip will stay with volume at 0 and if you delete the keyframes and put then again it stays the same no matter what value you put, is like if the keyframes don't work in the vse. I tested it in the latest build -blender-2.83-f06a6e92bc5e-linux64-

Richard Antalik commented

2020-03-19 15:07:12 +01:00

Added subscriber: @PranavjitVirdi