[Jeff Hartman]

Okay, I missed one point in the thread I meant to cover:

If you have embedded audio in one or more of your SDI sources that needs to be mixed, you will need a de-embedder; either the Blackmagic SDI to Audio converter or the Blackmagic SDI to Analog converter could work, though there are some differences. (The product cited in the thread is a different product that accomplishes the opposite function, embedding audio into the video).

Typically, your embedded SDI feed would hit the converter, and the Loop SDI Out would continue on to feed the ATEM. The converter’s audio output would go to your audio mixer.

Which miniconverter you choose would be based on what your audio mixer needs:

• If you only need analog feeds from the first stereo pair, the SDI to Analog converter will work just fine, and costs less ($295 list). It also provides analog video output, which you probably won’t use.

• If you need more than one stereo pair, or if your audio mixer needs AES rather than analog audio feeds, you need to use the SDI to Audio converter ($495 list).

— Jeff

[Jeff Hartman]

This thread is accumulating a number of incorrect statements, so here’s some background to try and clear up what the ATEM TVS does:

1) The unit has four SDI input connections and four HDMI input connections; you have access to six, of which two are always SDI, two are always HDMI, and the last two may be either SDI or HDMI. So if you need six SDI inputs, you will need two outboard SDI to HDMI converters.

2) The ATEM does not perform format conversions on the inputs; you need to set the ATEM to your desired program format (e.g., 720p, 1080i) and then ensure that every source matches that format — either by properly configuring the source, or by passing it through something like the Up/Down/Cross converter. A source that doesn’t match the switcher format simply won’t appear — you’ll get only black.

3) Embedded audio in a source feed does not pass through the ATEM.

4) The ATEM does have an unbalanced (BNC) AES audio input, which gets embedded into both the SDI and HDMI program outputs, and is encoded with the H.264 feed. To use this, you need an outboard audio mixer with an AES output, or a mixer with an analog output that is converted to AES.

5) The H.264 encoding is used solely to feed Blackmagic’s recording solution; it is not useful for live streaming. You will need some other device to take in the program feed and encode it for web streaming.

Hope this helps clear things up!

Regards,

Jeff Hartman
Engineering Project Manager
Newport Television, Northeast

[Jeff Hartman]

I tried this very thing, and with the possible exception of Carlos’ suggestion, the answer is no. With the Windows version, the problem is that the software stores the switcher’s IP address in the registry, so there’s no way to distinguish between several instances of the application. This is unfortunate; it would have been really handy to have the option to add the target switcher’s IP address in the application shortcut.

On the other hand, you can have several different computers simultaneously controlling the same ATEM. Once you get past the cheap thrill of moving the fader on one machine and watching it move on the other, there is a very practical purpose: while one person is actually switching on the main page, a second person on a different computer can be uploading graphics and controlling what’s in each media player channel.

— Jeff

[Jeff Hartman]

[Bret Williams] “You are misunderstanding. I understand all of that completely. But obviously a lot of people shoot 30p and there are plentiful of easy setups in FCP and Premiere for it with Matrox and other drivers. Blackmagic only supplies easy setups for the congenital broadcast formats. 720p60, 1080p24, and 1080i60. If you shot 720p30, it it excessive overhead to edit in a 720p60 sequence, doubling the size of your renders and forcing the processor to play back 60fps instead of 30. The intensity extreme may very well do a hardware conversion to 60p just to keep the 60hz for the TV, I dunno.

So now I forget. What was my question? Oh, yeah, why such limited presets? Matrox has a zillion more. Every config you can think of, and every ProRes codec for every config. You never need to set anything manually, which seems to be the downfall of so many.”

You are indeed correct, and I missed the premise that you were actually shooting 30fps… perhaps because I had a nearly identical conversation with one of our people about a month ago.

Putting on my design hat for a moment, the only reason I can think of for the limited selection is that possibly the options are constrained by the hardware, not the software. My guess is that Blackmagic tends to create products by starting with existing hardware (i.e. chipsets) and then writing software to produce specific functionality — as opposed to designing their own hardware from the ground up. Using already available chips really drives down the cost of development, but sometimes creates unforeseen limitations when software can’t quite accomplish everything you want the product to do.

— Jeff

[Jeff Hartman]

[Bret Williams] “I understand that 720p is really always 60p as far as the output of the device goes (has to be 60hz somehow) but the sequence doesn’t need to be 60p. That just adds overhead to the processor.”

Perhaps I’m misunderstanding what you mean… but 720p/60 (actually 59.94) is indeed 60 unique frames per second; it isn’t meaningless overhead at all. It still takes a while for those of us to have done interlaced NTSC for decades to get used to it…

I find that thinking of it strictly from a broadcast perspective helps:

• 720p provides sixty complete 1280×720 frames every second.

• 1080i provides thirty complete 1980×1080 frames every second (broken up into sixty interlaced fields). Each complete 1080i frame consists of slightly more than twice as many pixels as one 720p frame; since 1080i transmits half as many complete frames as 720p per second, the net result in data rate is close enough that either format can be practically encoded within an ATSC channel; this also accounts for either format being supported by 1.485Gb/s HD-SDI cabling and equipment.

• 1080p provides sixty complete 1980×1080 frames every second — that is, the same frame rate as 720p, and the same screen resolution as 1080i. As you would expect, since the number of complete 1080p frames is twice 1080i, the data rate doubles — and requires a 3G connection.

Other frame rates — 1080p/24, for instance — are targeted more at electronic cinema applications rather than broadcast… but you can infer the lower storage and processing requirements, compared with 1080p/60.

Regards,

— Jeff

[Jeff Hartman]

[Liudas Vasaris] “Does UpDownCross allow to input 16:9 SD and output 4:3 SD letterbox?
If it only allows convert from HD, who can do this?”

Unfortunately, the converter doesn’t seem to offer this particular conversion (I have the OpenGear version, but imagine the miniconverter is the same). We take an anamorphic (16:9) SD satellite feed, and need to produce both a 720p version and a center-cut SD, and wind up using two converters: the first to upconvert the anamorphic SD to 720p (which also corrects the geometric distortion), and the second to downconvert the 720p to the center-cut SD. I would prefer to avoid passing the SD through two cards, but right now it seems unavoidable.

One thing to be aware of: depending on which interim HD format you select, the converter might not pass closed captioning. This is a known bug that they’re planning to fix in an upcoming firmware revision.

Offhand I can’t think of a hardware reason why the converter shouldn’t be able to do the SD to SD conversion you want; perhaps they can revise their software to allow that particular combination.

Jeff Hartman
Engineering Project Manager
Newport Television, Northeast

[Jeff Hartman]

[Joshua Helling] “The software does not need to see the card (as in the utility). In the case of the UDC the only interaction for the software is the firmware update. This will happen when you plug in the device and start the utility. After the update there will be no further interaction from the GUI.”

So the fact that I can plug the card in and start the utility but nothing seems to happen — everything is greyed out and the top bar says “Blackmagic Converter Utility: No converter connected” — is normal, and means that there’s no firmware update pending for this particular card?

— Jeff

[Jeff Hartman]

[Joshua Helling] “This update, in some case the lock timing could be slower. So this has improved that situation for the UDC (it’s shorter than it was, but different formats will be different).

It did NOT address the CC translation lines for the UpDownCross, though it is still in the Bug Database to be addressed.”

I’m confused… how does this update apply to the UDC if the software doesn’t even see the card?

— Jeff

[Jeff Hartman]

Okay, just went back to my paperwork from mid-December when I tested the cards and originally reported the problem. Here are the specifics:

1080i in, NTSC out: captions OK
1080i in, 720p out: captions OK
1080i in, 1080i out: captions OK
720p in, NTSC out: no captions
720p in, 1080i out: no captions
720p in, 720p out: captions OK
NTSC in, NTSC out: captions OK
NTSC in, 720p out: no captions
NTSC in, 1080i out: no captions

Since we don’t have a way to generate or check for PAL captions, I didn’t test combinations involving that format.

Also, this is not a fluke with one card: we see the same results from four different cards.

— Jeff

[Jeff Hartman]

The specific issue is that the UDC fails to pass closed captions under certain combinations of input and output formats. The particular combinations that are most critical for my shop are between 720p and 480i; the card generally works between 1080i and 480i, but since we are mostly 720p that’s a big problem.

I worked out all of the combinations quite some time ago, and can dig them back up if necessary.

Thanks,

Jeff