Lumiere HD workflow

[Dylan Pank]

Hmm, interesting, especially the part that says that the HD100 does not record 24 frames per second to tape, but 60 frames, a la Varicam and DVX (fields rather than frames with the DVX but same principle).

Does this mean that the HD100 is also recording 60 frames when it's recording 30p mode as well?

So why no 60p in this camera? We know it can SCAN 60p at the CCDs as it can output 60p from the component outs.

[Barry Green]

That HDForIndies site is saying that their info is directly contradicting what Steve Mullen wrote, about ProHD recording a direct 24p stream. Interesting. Obviously somebody's got it wrong.

If there's pulldown, it'd be one duplicate frame, not an interleaved 60i style recording like the DVX/XL2 use. The JVC is based around HDV30p, so to get HDV24p they'd either invent their own format for 24p recording (as we thought they had, with ProHD) or they'd add one duplicate frame for every four "legit" frames. But still recording 30p.

I don't know why they don't record 60p though... HDV provides for 60p. Maybe today's codecs can't make a satisfactory image from 60 progressive 720p images crammed all into 19 megabits of space? Remember, HDV 720p is 19 megabits no matter what frame rate you're running it at, whether 25, 30, or 60.

[Murad Toor]

Mike's site is great. Thanks for the heads up.

[Frederic Lumiere]

ProHD 24 encodes only 24 frames per second but repeats these frames over 60 progressive frames.

The repeated frames are only 1 bit "repeat" flags. It doesn't do 60p encodes and I believe the obstacle here might be the sensor.

It's a great camera. Hopefully we'll have some footage to share with you soon.

Frederic

[Chris Hurd]

Hi Frederic,

It was great to see you at NAB (and also Mike Curtis; wish we could have had a photograph together). If you have any sort of press release information or other announcements regarding Lumiere, please be sure to post them here -- it's your forum after all! Cheers,

[Frederic Lumiere]

Chris,

It was good seeing you too! What a show...

The camera will output full 60p live from the component HD and I suspect the Firestore solution might be able to record 60p!

Frederic

[Radek Svoboda]

What will look better on a high end 1080p TV set, high end 25 Mbps 1080i60 HDV or high end 19 Mbps 720p60 HDV?

Radek

[Chris Hurd]

The bit rate really doesn't have that much to do with it. If you have a satellite receiver plugged into that set, then you'll be watching MPEG video compressed at a much higher rate than 19mbps.

There are some folks who perceive 720p to be "better" than 1080i due to the Kell factor. I think the real answer to your question is a subjective one, as in, which one looks better to you. And you're the only person who can answer that. You have a 1080p television in your home?

[Radek Svoboda]

I don't have 1080p TV. I just wanted to have expert opinion, Chris. Your answer is true but I would like to know what expert that runs this forum thinks.

Radek

[Jack Zhang]

ask Douglas S. Eagle, he's the expert, if he doesn't reply, E-mail him.

[Kevin Shaw]

Originally Posted by Radek Svoboda

What will look better on a high end 1080p TV set, high end 25 Mbps 1080i60 HDV or high end 19 Mbps 720p60 HDV?

Unless you have some sort of access to a 1080p display, a better question might be what looks better on a 720p display. Also, I'm not aware of any proposal for an HDV camera which records 720p60, so maybe you're thinking of the Panasonic DVCProHD camera?

In any case, any decent HD video should look better on a high-end HDTV than any SD video, with maybe a few exceptions under some unusual conditions.

[Radek Svoboda]

Originally Posted by Kevin Shaw

Unless you have some sort of access to a 1080p display, a better question might be what looks better on a 720p display. Also, I'm not aware of any proposal for an HDV camera which records 720p60, so maybe you're thinking of the Panasonic DVCProHD camera?

HDV spec includes 720/60p at 19 Mbps. It's probably just matter of time to see it in cameras. New top displays are 1080p.

Radek

[Eric Wotila]

Hey,

I'm trying to export a video to tape with Lumiere. I'm using an FX1. Here's my problem: After I take my uncompressed HD master and use Lumiere to convert it to a transport stream (yes, I did confirm it's set to FX1 export--not FX1E), when I hit print to tape the video seems to "offset" a bit. The left edge of the video is on the right edge of the screen--kind of like a poor tracking deal, but horizontally. Also, the audio seems to have sped up, so the audio and video are completely out of sync.

Has anybody else had a similar problem? Any known solutions?

Thanks for any help!

[Steve Mullen]

Originally Posted by Frederic Haubrich

ProHD 24 encodes only 24 frames per second but repeats these frames over 60 progressive frames.

Frederic

Great to see you at NAB.

The CCDs run at 48Hz. Unless the Anti-Juddder filter is turned on, every other frame is dropped.

The encoder can only record: 24, 25, and 30fps OR only 25 and 30fps. In no case, are 60 frames encoded or recorded.

Therefore, either 24p is recorded directly to tape (just as 25p is recorded to tape) OR the 24fps are placed (somehow) within the 30fps. This is not simple -- as the 24fps frames arrive at a rate of 1/24th second while the 30fps are recorded every 1/30th second.

This is why I have always believed that 720p24 is recorded just like 720p25 -- and 720p30. No repeat frames are needed.

What is confusing folks are the analog output and the i.LINK output. They may be very different.

1) Analog output is 720p50/720p60 or 1080i50/1080i60. This is true when shooting or playing back. When shooting or playing 24p, analog output is also 720p60 or 1080i60, but with 2:3:2:3 pulldown. Every NLE will understand this pulldown.

2A) The 24p comes down the i.LINK just like 25p and 30p.That's how 720p30 works now where you create a 720p60 Timeline and each incoming frame is doubled. In this case, the same thing will be done with 25p, and we'll get a 720p50 Timeline.

However, 24p would go directly into a 720p24 Timeline. This requires a new input option since video has never come in at 24fps.

2B) Upon playback, both 25p and 30p are frame-doubled in the camcorder to 720p50 and 720p60 and sent via i.LINK. This can be done because the Motion Filter has converted the CCD output at 720p50 and 720p60 to 25p and 30p. Thus, it can be converted back to 50p and 60p.

In this case, both will be input to the NLE as 720p50 and 720p60 -- just like DVCPRO HD. What will the camcorder do with 24p?

Ideally it would simply send 720p24 down i.LINK. Again, this requires a new input option since video has never come in at 24fps.

However, the camcorder can apply 2:3:2:3 pulldown to get 720p60. If this is the way it's done, then you'll have to remove the pulldown to get back to 24fps. The advantage is that the NLE will work just like it does now with 24fps in 720p60 video.

I frankly do not believe in some other "repeat frame" scheme. Either it's pure 24fps or 24fps is carried within an industry standard pulldown. I suspect pulldown is used because all NLE's understand 24fps within 60p or 60i. No new software will be required.

All that's needed is that the i.LINK driver recognize the HD-100 and its range of options. Clearly Avid already knows how to do this since they were demonstrating it at NAB. I expect Apple to have an HD100 update in July, before Avids ships.

[Graeme Nattress]

But, as Frederic says, the MPEG2 stream coming down that firewire cable is a 60fps stream, not a 24p one, but it only contains data for 24 out of those 60 frames, with the extra frames being small pointers to one of the real 24 frames that gets duplicated. If you just put the MPEG2 stream straight into a MPEG decoder, it sees 60fps and gives you a 60fps video with the 24 real frames embedded into it.

Graeme