MPEG2 Muxed

[Jeremy G. butler]

I would assume so? Just to save with file-size constraints I’m using an SD feed – so I tell it to encode with NTSC – DV/DVCPRO. It’s a setting that I’ve used for five or so years on my G5 with SD material. And just to verify that the file itself was okay I opened it in VLC and everything is groovy. I admittedly am not too well versed in Streamclip, though it does seem to be pretty straightforward, so I’m open to any and all suggestions.

[Michael Magallon]

Hey Jeremy,

What ingest/playback solution do you use, PathFire, Vela?

The reason why you are seeing the white screen from your file in QT player is that although MPEG2 is a CODEC that it can see, it will not see 422p, where the chroma sub-sampling is 4:2:2, not 4:2:0 or lower. Saying that you are using broadcast equipment, I am sure that it is outputting 4:2:2, Transport Streams.

VLC player will playback most profile and levels in the MPEG2 specification, that’s why you can see your files. MPEG STREAM Clip works of the QT components, that why you can’t see the file in MSC, because of QT.

The no audio is interesting however. More than likely, they will be outputting M1L2 audio, usually at 384kbps. Please verify that you are not outputting SMPTE 302 audio, as this will open a whole other can of worms!

What ultimately do you want to do with the files? Transcode them to play online? edit them? store them?

You will definitely need to transcode them. The bad news is that there is currently no Mac solution to transcode 422p@any level MPEG2 Transport Streams to QT files.

We use PC solutions for this.

Anyway, let me know of your workflow and I can probably help.

—
MM

[Jeremy G. butler]

As far as the specifics of our ingest/playback, I’ll need to get our Chief Engineer to answer those questions. I know we have a Pathfire machine, but I’m not entirely sure how it all fits into the overall scheme of things.

As far as the rest, my intention is to be able to import the files into FCP6 and edit. I’m pulling things like the Network Promo Feed in HD and other various syndicated what nots – so I’ll be using this “drag-n-drop” network method as opposed to having Master put the feeds onto tape and my having to capture them into FCP. The last time I talked to our chief he was looking into seeing if he could get the ingest server to NOT mux the files, but I’m not sure where he is on that. He’s out of the office at the moment but the next time I see him I’ll have him answer those questions and we’ll see where we are.

Thanks a million times over!!

[Michael Magallon]

Are you by chance using SkyMicro?

What I would recommend:
Take the SD HD/SDI output from the back of the SkyMicro, use a capture card such as BlackMagic, AJA or Matrox MXO2 (recommended to keep CC’s) and capture to whatever CODEC you want in your FCP! I would recommend ProRes.

This way, the baseband output will be on any batch bay, video router.

Would that be an option?

—
MM

[Jeremy G. butler]

I don’t know, honestly. haha

Not that I don’t appreciate the input, but what would probably be most helpful is a solution on my end. In an perfect world…well, in a perfect world I wouldn’t even need to start this thread but I digress…in a preferred world, nothing would need to be changed in Master. They have their own setup that works and I don’t want to have to have them reconfigure anything or go to any extra steps just to accommodate my one little Mac.

If there’s a PC solution that would be an option as well – I have a Gateway Laptop that I integrate into my suite every day (mainly just because it’s my personal machine and I feel better checking things like e-mail and Facebook on my computer as opposed to the company’s equipment) and I could very easily put the file on there, do whatever needs to be done, then jump drive it or external hard drive it back to the Mac. My only concern on that front is that some of these HD feeds come out to about 6gig files and it’s no powerhouse of a machine or anything. I’ve had someone mention ffmpegx – is that just another rabbit hole or is it something worth looking into?

[Michael Magallon]

Believe me I understand, just trying to spitball ideas 🙂

Anyway, your laptop should just stay as is. I totally forgot about ffmpegX! Yes this should work with your files.
It will be a lengthy transcode though. ffmpegX uses mplayer to decode the 422p@whatever level and then mencoder to encode.

The only problem is that ffmpegX does NOT use QT API’s for output. What does this mean, your only output option is DV/HDV.

Use this nifty preset that I quickly created to test on the Mac. Just create a new text document using TextEdit, copy and paste the below and rename the extension to whateveryouwant.ffx:

ffmpegX Preset File
_version=14

_encoder=ffmpeg
_video=true
_videoformat=13
_width=720
_height=480
_ratio=8
_videobitrate=25000
_framerate=NTSC (29.97)

_gopsize=240
_minq=2
_maxq=15
_highquality=true
_iframes=false
_bframes=false
_fourmotion=false
_twopass=true
_profile=0
_qtdecode=false
_split=false
_chunks=0
_author=false
_authorformat=0
_deinterlace=false

_croptop=0
_cropbottom=0
_cropleft=0
_cropright=0

_audio=true
_audioformat=5
_audiobitrate=1411
_audiosampling=48000
_audiogain=0
_audiochannels=0
_audiomode=0
_invertmap=false

—
MM

[Jeremy G. butler]

BEAUTIFUL! Pardon a potentially dumb question – but what would I have to change in those values to transcode an HD file? Unless I’m mistaken, the feeds come down in 1080 since we’re a CBS Affiliate – but I’d have to verify that before I could say with any certainty.

[Michael Magallon]

Oh, duh, my bad, you did say HD.

Yeeah you can change the values OR you can use the supplied preset as a starting point and build from there.

I built the rod, now learn to fish 🙂

—
MM

[Michael Magallon]

sorry, didn’t answer your question directly, change ONLY these values:

_width=720
_height=480

to

_width=1920
_height=1080

—
MM

[Jeremy G. butler]

Fantastic – I’ll give it a test run a little later tonight and will let you know how it goes.