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Encoded video fps is wrong
Closed, ResolvedPublicBUG

Description

System Information
Operating system: Gentoo Linux
Graphics card: AMD 580

Blender Version
Broken: master
Worked: 2.93

Short description of error
After we moved to the new non deprecated encoding/decoding ffmpeg APIs, ffmpeg encoded videos would sometimes have the wrong FPS.
This is a issue with older ffmpeg versions, so we need to bump our minimal ffmpeg version to 4.4.

Exact steps for others to reproduce the error

  1. Open the provided .blend file
  2. Render out the video
  3. See that the video file does not have a FPS of 24.0

FPS can be checked from command line with: ffprobe /tmp/0101-0111.mp4

Event Timeline

Sebastian Parborg (zeddb) changed the task status from Needs Triage to Confirmed.Tue, May 25, 4:06 PM
Sebastian Parborg (zeddb) triaged this task as High priority.
Sebastian Parborg (zeddb) created this task.

I can confirm this is fixes by linking against FFmpeg 4.4.

I have the windows libs ready, but during testing i hit a snag, i'm not seeing a difference between 4.3.2 and 4.4 scratch that, used a too old build for testing 4.2.3 that did not have the issue yet, can confirm 4.2.3 was bad, and 4.4 fixes the issue on windows.

c:\tmp>ffprobe -v error -select_streams v -of default=noprint_wrappers=1:nokey=1 -show_entries stream=r_frame_rate 0101-0111_423.mp4
24/1

c:\tmp>ffprobe -v error -select_streams v -of default=noprint_wrappers=1:nokey=1 -show_entries stream=r_frame_rate 0101-0111_44.mp4
24/1

After some collaboration with Sergey, I've created a fix for ffmpeg < 4.4 : https://developer.blender.org/D11417

Aaron Carlisle (Blendify) changed the subtype of this task from "Report" to "Bug".Fri, May 28, 9:33 PM
Aaron Carlisle (Blendify) moved this task from Backlog to bcon3: Bugs on the BF Blender (3.0) board.
Sebastian Parborg (zeddb) claimed this task.