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12th February 2014, 18:25 | #1 | Link |
Registered User
Join Date: Dec 2007
Posts: 2
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Different file size after changing container format
I was looking for a way to convert .ts files to .mkv without modifying/re-encoding the audio and video, and a quick Google search told me that MKVToolNix is ideal for doing this. I just tested it by converting a few videos with h264 video and aac audio in .ts containers to mkv.
It seems like everything worked fine, and the process was nearly instant. However I notice that there is a difference in file size after conversion. The new mkv files seem to be about 5-10% smaller than the ts originals. I was under the impression that the container format contributed little or nothing to the overall file size, so changing it should have little effect. Is that incorrect, or have I lost something else in the conversion process? I don't think I've inadvertently re-encoded or modified the video/audio in any way. (I only ask because I'm unfamiliar with this software.) Re-encoding usually takes a noticeable amount of time and system resources, right? |
12th February 2014, 18:27 | #2 | Link |
Registered Developer
Join Date: Mar 2010
Location: Hamburg/Germany
Posts: 10,348
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TS files can contain (useless) filler data to achieve a certain fixed bitrate. MKVToolNix removes this filler data, which is why the resulting MKV files are a few percent smaller.
Additionally, TS has a bigger overhead than MKV, so its expected for files to be smaller - how much I cannot say for sure.
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Tags |
container, convert, mkv, size |
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