Just making sure: Converting AVCHD (h.264) to MOV (h.264) via FCPX before editing in PPro means one generation quality loss

[Shane Ross]

Why would you do that? Why convert H.264 to H.264? It doesn’t matter what wrapper it’s in, it’s a highly compressed format no matter how you slice it. Why not convert to something easier to edit, like ProRes? yes, you’ll be recompressing and that does lose a little resolution. But I challenge you to see the difference.

Shane
Little Frog Post
Read my blog, Little Frog in High Def

[Yair Bartal]

Thanks Shane,
Well, the reason is my colleague already did the conversion and I wanted to make sure that isn’t the right route.
Indeed, practically I couldn’t see the difference.

[Shane Ross]

Just wondering WHY they did that? PPro reads AVCHD files fine…and that H.264 is no easier to deal with than MOV H.264.

Shane
Little Frog Post
Read my blog, Little Frog in High Def

[Yair Bartal]

The reason is: We are a group of docs creators sharing two cameras and thus it happens that several projects are spread over several SD cards (I know it’s not a good practice). That one lady wanted her project’s material backed up for her separately on her portable disk.
It was easy to choose and pick up her files via FCPX and export those as single files (without the AVCHD folder structure which includes other projects).

[Gary Huff]

[Yair Bartal] “It was easy to choose and pick up her files via FCPX and export those as single files (without the AVCHD folder structure which includes other projects).”

Does FCPX rewrap AVCHD material into QuickTime? It’s possible if you ingest into the Library itself, as opposed to leaving the media in its location.

That said, tools like EditReady exist in order to re-wrap footage into QuickTime files without re-encoding. I used to use this all the time because it was far simpler to navigate folders for specific clips.

However, even without all that, SD cards are incredibly cheap. There is no reason to be filming multiple client projects on a single card.

I’m going to say that this material’s quality or lack thereof is probably not going to be an issue. However, with a re-encode from AVCHD to H.264 QuickTime and then an upload to any video sharing service is going to be three generations removed from the source, a pipeline of which will always be 8-bit 4:2:0 and low-bitrate throughout. I personally don’t like the idea of that, but it is what it is, and a lot of people simply don’t concern themselves with any loss generated by a process such as that.

[Yair Bartal]

Thanks Gary,

FCPX does not rewrap AVCHD material into QuickTime.
That’s why tools like EditReady exist.

[Gary Huff]

[Yair Bartal] “FCPX does not rewrap AVCHD material into QuickTime. That’s why tools like EditReady exist.”

Hey Yair, probably best not to state things like this unless you have first-hand experience. I actually just tested this out because I was pretty sure I had remembered that FCPX re-wrapped AVCHD into QuickTime, and it absolutely does.

EditReady has other reasons why I used it (there was a 30p issue with AVCHD from the C100 for a while), and it is absolutely a must-buy for anyone who works a lot with AVCHD.

[Yair Bartal]

Hey Gary, you’re correct in that I should’ve added: “to the best of my knowledge”.
Now I’d appreciate if you can explain exactly how you used FCPX to re-wrap AVCHD into QuickTime, and especially what makes you sure this is indeed a re-wrap and not a re-compress process.

[Gary Huff]

[Yair Bartal] “Now I’d appreciate if you can explain exactly how you used FCPX to re-wrap AVCHD into QuickTime, and especially what makes you sure this is indeed a re-wrap and not a re-compress process.”

No need to be flippant, Yair. You import the footage and tell it to ingest into the library. And there’s no way it can be a re-compression because the only thing FCPX recompresses into is ProRes, and the process of ingestion is far too quick to be a re-encode. Plus, the details for the resulting QuickTime file are the same as for the .MTS. There’s no reason FCPX cannot simple re-wrap the container.

[Yair Bartal]

Gary, I’m not flippant and I apologize if this is the impression you’ve got.
We may have a different definition of re-wraping vs re-compressing.
As far as I know re-wraping means no transcoding from one codec to another.
Once you ingest into the library, you do transcode once from h.264 to ProRes.
Then you export from ProRes to QuickTime with h.264 codec, that means you transcode again.
IMHO there’s no way you can call this whole process from mts(h.264) to QuickTime(h.264) a re-wrap of h.264.
I’d be glad to learn otherwise if that is the case.