Does ProRes preserve closed captioning from TAPES?
by Drew Sawyer
on
May 29, 2008 at 6:57:08 pm
Hello folks,
I just digitized several hours of footage from HDCam and brought it in as ProRes material. I was wondering if when I send this footage back out to TAPE if the Closed Captions that the tapes might have contained will still be there? Is uncompressed video capture the only way to go to capture CC's? Does it have to be done in 10-bit or 8-bit? Also, is there anyway I can check to see of CC's are present in FCP?
Re: Does ProRes preserve closed captioning from TAPES? by gary adcock on May 29, 2008 at 9:00:15 pm
[Drew Sawyer]"I just digitized several hours of footage from HDCam and brought it in as ProRes material. I was wondering if when I send this footage back out to TAPE if the Closed Captions that the tapes might have contained will still be there?"
Sorry No,
FCP strips all of this data away on capture, no matter what format it is captured to - most NLE's do -
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Inside look at the IoHD
Re: Does ProRes preserve closed captioning from TAPES? by Drew Sawyer on May 30, 2008 at 1:59:56 pm
-I heard that Capturing with an SDI card at uncompressed, like a Black Magick card might work. Anyone have any success at all on bringing CC's?
-Is there anyway to capture the Closed Caption with the video and place it into an NLE for laying back to tape? Is the NLE stripping the data in the coming in or in going out process?
Re: Does ProRes preserve closed captioning from TAPES? by Drew Sawyer on May 30, 2008 at 7:48:05 pm
Oh I read it. I also just thought since it was a forum I'd try to get a few opinions since I had read other dead threads with mixed responses. I didn't know you were the authority on whether my questions were completely answered or not. Thanks.
Re: Does ProRes preserve closed captioning from TAPES? by Rich Rubasch on May 30, 2008 at 8:47:00 pm
Admittedly there are a few who have a tendency to come across as the end all to a posed question on these forums. They might seem less than helpful. But I think everyone here means well.
I do wish that "some" would curb the condescending answers, especially when someone is pretty obviously probing for more info.
Re: Does ProRes preserve closed captioning from TAPES? by gary adcock on May 30, 2008 at 9:40:42 pm
for the record I am no expert on Closed Captioning, but I do work with it a fair amount.
CC data is not something that any average user ever comes into contact with except when they accidently cannot turn it off on their TV set, I bet 85% of the people on this list may never create or have to work with CC data - so I assume the person asking this kind of question to at least have basic knowledge of what is involved with handling and creating CC content.
had the followup question been asking for further explanation or other peoples experiences on the subject the response may have been different.
CC data is a very serious matter as I have friends and family members that rely on the need for closed captioning on content, so trying to "get by" with using existing data on a tape peeve that I should have voiced.
Final Cut Pro that strips away all of the ancillary metadata on capture- in every codec, with everyone's hardware.
CC data needs to be continuous- much like a TC track so it is not as easy as one might think to handle that data in this manner in post- hence the reason it is usually laid directly to a final tape after the picture and sound have been locked and usually only on the broadcast masters
the CC data stream on a tape is not usable to make DVDs since it is carried in a different place in the mpeg stream than it is in baseband video.
CC data for SD and HD are not interchangeable, and I only know of very few devices that can convert between the 2 line positions-- AJA, Teranex, Snell and Wllcox are the only companies I know of that are on the market ( at NAB) that can correctly convert CC data between the formats.
Drew --rather than play a guessing game - why don't you explain to us what you are planning on doing with the content that requires you to maintain this data, so that you can get opinions on it.
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Inside look at the IoHD
Re: Does ProRes preserve closed captioning from TAPES? by Sean ONeil on May 31, 2008 at 7:26:43 am
[Drew Sawyer]"I didn't know you were the authority on whether my questions were completely answered or not. "
LOL! Well actually... he's one of the closest things to it :). That's fine you want a second opinion. But it's not cool to pretend like he didn't answer you. A less obnoxious response would be directed at Gary saying "Are you sure? I've heard different information? Can anyone else confirm this, etc." Instead, to me it looked like you didn't like the answer he gave, so you chose to ignore him.
Re: Does ProRes preserve closed captioning from TAPES? by Andy Mees on May 31, 2008 at 4:21:12 am
Afaik and this is purely anecdotal form forums such as these, CC on Line 21 is/was preserved when capturing Uncompressed using Blackmagic Design Decklink hardware with FCP ... or at least, it used to be so. Perhaps more recent hardware and drivers have lost or disabled this capability? Either way, the usual issue is that FCP in and of itself does not support/preserve this data, so that any renedring whatsoever will strip the data. So if you capture it and then play it straight back out you;d be fine, but post process in any way and its lost.
Apologies to Gary if I just muddied the waters with old and outdated info
Re: Does ProRes preserve closed captioning from TAPES? by Jim Calahan on May 31, 2008 at 5:38:05 am
ProRes does capture line 21 data in SD as it's 720 by 486 but if you insert anything into it it will destroy that data like Andy says. I haven't tried to save caption and other HD-VANC space data from HDCam yet as 708 captions are a whole different animal. If and when I get time to play I'll report back (Christmas maybe). So far we just master to HDCam for our PBS/APT submissions.
Re: Does ProRes preserve closed captioning from TAPES? by gary adcock on May 31, 2008 at 3:23:56 pm
[Jim Calahan]"ProRes does capture line 21 data in SD as it's 720 by 486 "
IN FCP?
If so I stand corrected on the SD CC capture.
I was always able to do it correctly in other capture utilities (VTR xchange, Virtual VTR, and in a number of wintel apps), but in all of my HD testing the CC data is no longer there (in correct placement) when the content is captured thru the Final Cut interface.
--according to a mutual friend of yours and mine in grass valley, one of the biggest issues with ProRes/ FCP 6 is the striping off of all ancillary metadata.
"if you insert anything into it it will destroy that data like Andy says."
Correct- hence the reason I asked for a better explanation of the purpose of wanting to capture that content ....
and
Thanks to Sean for the support
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Inside look at the IoHD
Re: Does ProRes preserve closed captioning from TAPES? by Drew Sawyer on May 31, 2008 at 4:57:06 pm
My apologies for being short with you Gary.
I am doing a cut and trim of a television program. Im actually preserving the entirety of the program, just removing commercials. Everything is coming in on HDCam 1080i tapes. Im using an out of house tape-digitizing facility, and it donged on me, "wait, I wonder if these programs have CC?" Although they were not labeled with CC on slate or on the tapebox, and the digitized data files were already delivered to me, and I couldn't find traces of CCs. Regardless, I can find out which programs do and don't have CC with the producer. But I didn't know of any way to bring in HD material with CC's, apply a new lower third across the whole program, trim out black space, and maintain the CC data if it was present. I am familiar with "line 21" for SD, but I have no knowledge of HD CC data, nor have I worked with CC data before.
-The Real Issue
So I was wondering if there is any workflow for applying a graphic layer of video on top of captured HD video, and still preserve the CC data. Then lay it back to tape. If so what are the capture methods, and is it possible in Final Cut to add the said graphic layer without destroying the CC data.
I have heard of people cropping the 2nd video layer to a point in SD footage so that the line 21 data would still be present on the video layer below, but I don't understand HD CCs at all. Im researching them at the moment. Thanks for the ideas guys. I'll post my results. And please keep me informed of any new information.
Re: Does ProRes preserve closed captioning from TAPES? by Andy Mees on Jun 1, 2008 at 1:49:33 am
if you were just trimming out black space, commercials etc you'd be fine ...
from the Blackmagic Decklink HD webpage:
Access VANC Blanking Data Capture and playback any line of blanking, using any of the top three lines of your media file. This lets you store test signals, timecode, subtitles and many other custom types of data.
...but laying that graphic throughout is what's going to kill it. Just a thought, but if you have the hardware you might be able to utilse the Blackmagic's Live Key application to overlay the graphic on your edit master and so bypass the render in FCP that'll strip that important data.
