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Proper MPEG cutting without re-encoding

Started by sv, February 04, 2013, 07:05:57 PM

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sv

Hi all,

I'm trying to cut an VCD (.mpg) file without re-encoding the whole thing. Video and audio outputs are set to copy and the container is Mpeg-PS Muxer with VCD as the muxing format, therefore I should be using the correct settings. Yet, when saving the scenes, I noticed that the whole parts are being re-encoded by checking the CPU usage and the slowness of the process, the so-called "smart rendering" wasn't being used at all. Now if I use Mpeg-TS, then it's done as it should but resulting in a much larger file size than the original and I've come to the understanding Mpeg-TS should only be used for lossy transmission.
I'm fine with the high CPU usage but I don't want to lose quality by re-encoding each and every scene.

sv

Trying it with 2.5 now. When saving the file as MPEG-PS (VCD), I get "Incompatible audio - For DVD, audio must be 48khz MP2(stereo), AC3, DTS or LPCM (stereo)", yet I specifically selected VCD as the output and not DVD. This is either an obvious bug or I'm missing something. Any help or ideas? Nightly builds all crash at start-up for me.

macduke

Hi.
Avidemux version?
Have you selected "Allow non compliant stream" on "Output Format">Configure?
On second try, have you selected "Accept non audio standard frequency for DVD" on Edit>Preferences>Output ?

      Mac.

sv

Hey and thanks for replying,

The "incompatible audio" bug I got was with version 2.5.6-1, I can't seem to find "Accept non audio standard frequency for DVD" anywhere in the settings. "Allow compliant stream doesn't work either", same error message.

I managed to get the nightly builds working after deleting the previous 2.6x build from the directory.
Yet, I'm still getting 100% CPU usage on one core when encoding (suppose the mpeg encoder doesn't support multi-cores).
No matter which of the Mpeg-PS setting combinations I try, I always get full CPU usage in the saving process. I'm starting to think if this is standard behavior? Mpeg-TS working as it should, much faster with no re-encoding - yet, I was under the impression it's how it should work with PS as well.

zakk