I thought it might be useful to have a tool that makes it quick and easy to collect this information, so I started working on one. One thing I am curious about: has anyone seen any seamless branching discs that reference a M2TS file more than once - i.e. branch into another M2TS file and then back to a former one at a higher time offset? At the moment, I'm just adding together M2TS file sizes to determine a MPLS playlist "size" - i.e. the "Movie Size", but that might not be a safe assumption.
I know many of the "garbage" MPLS playlist files repeat the same M2TS file over and over again, but I haven't seen any main titles do this even though it seems like a possibility. At the same time, I don't believe any of the current muxing/demuxing tools support setting in/out times for a M2TS so it must be fairly rare if it happens at all.
At the moment, I've got the MPLS parsing complete and a good chunk of the M2TS parsing done. However, only the AC3 payload scanning for extra details (bitrate, channel count/layout, etc.) is finished (albeit not shown in the screenshot below), so I've still got to tackle all of the other video and audio codecs. In terms of video bitrate, I haven't decided whether to take an estimation approach or try to calculate it for real (the latter might actually be easier).
Oh yeah, here's the work-in-progress screenshot

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