Compressing and replacing captured .mkv

Problem: We have a captured file of size 414mb. We have already edited the capture with many cuts, speed adjustments etc. The output size is about 120mb. Video duration after edit is about 20 minutes.

Now, the problem is since we have many cuts in the file, HTML5 output played in any browser does not give good user experience. When user navigates randomly on the timeline, browser takes time to display the video file available at that time duration. Resources folder shows 113 .mp4 files. So, switching from one file to another is the difficulty for browser. Pasted timeline on one of the slide.

Please suggest solutions on following points:

  • How to compress .mkv (which is 400mb+ in this case)
  • If we compress .mkv from external software, is it possible to replace the source? Since AP generates resources such as Source_2_2.
  • How to control the output file by not really compressing the video compression less than 60.

Benchmark at our end: 30+ minutes video output generated in the past on other machine using same capture resolution is about 90mb. For current video we anticipate the size not more than 75mb.

ActivePresenter version: captured on 8.3.1 and edited on 8.3.2 (both are different machines)

OS: WIN10 on both machines

Hi Shri,

The Join Audio/Video Objects feature can help you to solve the HTML5 output problem.
Please refer to the Join Multiple Videos part in this article for detail: How to Split and Join Videos in ActivePresenter 8 - Atomi Systems, Inc.

Suggest solutions for your points:

Yes, you can compress .mkv from external software but you have to keep the file name unchanged.

The current version only has the Quality option, unfortunately.

Can you please send your project and its external data folder (named PROJECT_FILE_files) via so we can take a look?


Thanks for prompt reply.

Will check this and update here. Thanks for this workaround!

If I have to use compressed .mkv after the file is edited, how can AP file use it? I don’t know how does it work because source is already imported and many cuts are applied on source layer.

I don’t think sharing a file would be possible due to IP issue. Will reach out to you in case this method doesn’t work.



After the file is edited, it creates logical resources linked to the resource file. This will be processed when exporting, so you can replace the resource file.
Or you can right-click the resources > Export and then import them again.


I have 116 sources in a 20 min video. Any better solution?

Replacing single .mkv (first file) is okay but how to replace cut parts with file names ending with _2 (image below).

Hi Shri,

You need to compress only the .mkv file.
The process is as follows:

  1. Close your project.
  2. Look for the mkv file in your project external data folder (which has the name in the form projectFileName_files)
  3. Backup the mkv file to another location, compress and replace the file in the data folder.
  4. Open your project and check if it works properly.