Incorrect behavior of speed control strip when based on soft-trimmed input strip #45191

New Issue

Willi · 2015-06-25T16:01:46+02:00

Willi commented

2015-06-25 16:01:46 +02:00

System Information
Win7/64, GTX 750 Ti

Blender Version
2.74 official, 2.75-42314b3-win64

Short description of error
Whenever a speed control strip is based on a soft-trimmed input strip, the frame mapping is not right.

Exact steps for others to reproduce the error
Please open VSE Speedcontrol.blend.

Description:
The file contains two scenes named "Scene" and "Video":

Scene "Scene" displays letters A to J. Frame range is 0 to 9 (10 frames). Letters instead of numbers have been used to avoid a 0-based/1-based confusion.
Scene "Video" is only used for the VSE. Channel 1 contains a scene strip. The soft-trim start is 4, i.e. letters A, B, C and D have been trimmed. Consequently, 6 letters are left (E to J).

Now, the goal is to playback these 6 letters at 50% speed. This results in 12 frames with each letter being rendered twice, so the expected final sequence is EEFFGGHHIIJJ. The steps are:

Slide the right arrow of the strip to the right by 6 frames.
Add a speed control strip.

The resulting image sequence is EEFFGHHIJJJJ (Blender 2.74) or EEFGGHIIJJJJ (Build 42314b3)
The expected image sequence is EEFFGGHHIIJJ (each letter twice)

This is probably because soft trimming has not been taken into account correctly.

**System Information** Win7/64, GTX 750 Ti **Blender Version** 2.74 official, 2.75-42314b3-win64 **Short description of error** Whenever a speed control strip is based on a soft-trimmed input strip, the frame mapping is not right. **Exact steps for others to reproduce the error** Please open [VSE Speedcontrol.blend](https://archive.blender.org/developer/F197325/VSE_Speedcontrol.blend). Description: The file contains two scenes named "Scene" and "Video": - Scene "Scene" displays letters A to J. Frame range is 0 to 9 (10 frames). Letters instead of numbers have been used to avoid a 0-based/1-based confusion. - Scene "Video" is only used for the VSE. Channel 1 contains a scene strip. The soft-trim start is 4, i.e. letters A, B, C and D have been trimmed. Consequently, 6 letters are left (E to J). Now, the goal is to playback these 6 letters at 50% speed. This results in 12 frames with each letter being rendered twice, so the expected final sequence is EEFFGGHHIIJJ. The steps are: - Slide the right arrow of the strip to the right by 6 frames. - Add a speed control strip. The resulting image sequence is EEFFGHHIJJJJ (Blender 2.74) or EEFGGHIIJJJJ (Build 42314b3) The expected image sequence is EEFFGGHHIIJJ (each letter twice) This is probably because soft trimming has not been taken into account correctly.

Willi commented

2015-06-25 16:01:46 +02:00

Changed status to: 'Open'

Willi commented

2015-06-25 16:01:46 +02:00

Added subscriber: @willi-2

Antonis Ryakiotakis commented

2015-06-25 19:25:29 +02:00

Added subscriber: @Psy-Fi

Antonis Ryakiotakis commented

2015-06-25 19:25:29 +02:00

You are right, code works from start of strip data, not start of soft trim point and logic is somewhat weird. I'll see if I can improve it. I feel like the speed strip is too straightforward not to be easily understood by both coders and users and clearly this is not the case here.

blender-admin commented

2015-06-25 19:49:08 +02:00

This issue was referenced by 0e83b0854f

This issue was referenced by 0e83b0854fc66af16dd187759c031e530ecd4c05

Antonis Ryakiotakis commented

2015-06-25 19:52:09 +02:00

Changed status from 'Open' to: 'Resolved'

Antonis Ryakiotakis closed this issue

2015-06-25 19:52:09 +02:00

blender-admin commented

2015-09-08 16:36:15 +02:00

This issue was referenced by 91264cfdd0

This issue was referenced by 91264cfdd05722422f77599f22d28aa093af7c1e

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Incorrect behavior of speed control strip when based on soft-trimmed input strip #45191