MKV versus TS

[sark]

Hi all.

If I'm ultimately burning camcorder footage to DVD-R (AVCHD) for full HD playback on a Blu-ray player (authoring with tsMuxeR, or multiAVCHD), what is the better option when saving original M2TS files from Avidemux.
If all I'm doing is trimming in copy mode, is there any benefit between MKV, the default, over TS which I assume is closest to the original format.

Googling seems to imply MKV is more a choice of those re-authoring? Does the choice really matter if the original video only contains a video stream and audio stream.

Thanks in advance

Mark

[eumagga0x2a]

If you author a Blu-ray (a Blu-ray structure, no matter what medium you use to store it), video and audio must be in M2TS format. If you don't author a Blu-ray structure, it really doesn't matter beyond sticking with containers and codecs supported by the targeted player. Using MKV or MP4 might save some storage space compared to MPEG-TS.

[sark]

tsMuxeR and multiAVCHD will generate the M2TS as part of the AVCHD output. I just wondered if it mattered what you fed them with.
I'm guessing as long as the streams are compliant it doesn't matter?

Mark

[eumagga0x2a]

If you need AVCHD format, then use it, with video and audio as M2TS type of MPEG-TS and the specific directory structure.

If your equipment is happy with media files like MP4 or MKV containers on an ISO filesystem, then it is fine to use such formats.

I don't know the specific requirements and features of the applications you mention. If they create M2TS stream on their own without re-encoding the input, feeding M2TS to them would avoid conversion between ISO and AnnexB types of H.264 stream, but that's it.

[sark]

feeding M2TS to them would avoid conversion between ISO and AnnexB types of H.264 stream, but that's it.

Just out of interest. Would that also apply when feeding them TS (as available in Avidemux).

[eumagga0x2a]

No, normal MPEG-TS (the one with 188 bytes long packets) is by definition already AnnexB.

Depending on how sophisticated the application which converts between formats is, the only case where MKV may be not a good choice is the case of streams with timestamps being not a multiple of a millisecond and fps being a fraction like 30000/1001 or 24000/1001 frames per second. In this case, MKV timestamps, which usually have 1 ms precision, are only approximations and the application should guess which timebase they are meant to approximate (Avidemux does this, ffmpeg does not). MPEG-TS uses 1/90000 as time base, which allows to express timestamps at all standard fps values (24000/1001, 24, 25, 30000/1001, 30, 50, 60000/1001 and 60) exactly.