HVX202E- No Progessive 1080 25p? What's a 2:2 pulldown? at DVinfo.net

John M Burkhart · April 7th, 2006, 01:48 AM

According to Panasonics brochure for the PAL version of the HVX200 (202E)

(found here: http://panasonic.com.au/content/libr...es/F001688.pdf)

In the fine print on page 5 it says that 1080 25p recording is actually recorded in 50i by a 2:2 pull down.

Is that just a fancy name for field doubling?

Does the PAL version of this camera actually record in "true" progressive 1080? or am I just reading this wrong?

JB

Barry Green · April 7th, 2006, 01:58 AM

It's true progressive imaging, not field doubling.

It means that each frame gets printed onto two fields of video, so essentially the progressive frame is sliced into two halves; one gets recorded on one field, the other on the other field.

Field Doubling would mean that the same information gets recorded onto both fields (or, even more accurately, that the information from the previous field gets repeated onto the odd field).

In 1080/25p mode the HVX works using basically the same progressive-segmented frame technique as the CineAlta does.

The codec is an interlaced codec, so the progressive information gets transported within the interlaced wrapper. But when editing, you'll be editing true progressive.

John M Burkhart · April 7th, 2006, 02:00 AM

Thanks Barry for clearing that up.

How is this different than the 1080 30p captured by the US versions?

Barry Green · April 7th, 2006, 09:29 AM

It's identical in method, the only difference is the actual frame rate. 1080/30P in the US version is recorded within a 1080/60i stream using 2:2 pulldown. 1080/25P in the EU version is recorded within a 1080/50i stream using 2:2 pulldown. It's the same thing.

Alvise Tedesco · April 9th, 2006, 04:03 AM

Quote:

Originally Posted by Barry Green

It's true progressive imaging, not field doubling.

It means that each frame gets printed onto two fields of video, so essentially the progressive frame is sliced into two halves; one gets recorded on one field, the other on the other field.

Field Doubling would mean that the same information gets recorded onto both fields (or, even more accurately, that the information from the previous field gets repeated onto the odd field).

I don't get it 100%. If you would look at a single field, you would see odd + even lines till half of the picture and 0 signal for the other half?
Thanks

Barry Green · April 10th, 2006, 02:59 AM

No... fields are the full height of the picture, but alternating lines. So lines 0, 2, 4, 6, 8 etc are in one field, and 1, 3, 5, 7, 9 etc. are in the other field.

In a field-doubling system, field 0 gets displayed on the even lines, and then instead of displaying field 1 on the odd lines, the system displays field 0 again on the odd lines. The result is that you get half the vertical resolution, but you get the temporal motion signature of a progressive-scan image. Sony cameras use field-doubling when you go into slow-shutter modes, for example.

April 7th, 2006, 01:48 AM	#1
John M Burkhart Regular Crew Join Date: Apr 2005 Location: Singapore Posts: 97	HVX202E- No Progessive 1080 25p? What's a 2:2 pulldown? According to Panasonics brochure for the PAL version of the HVX200 (202E) (found here: http://panasonic.com.au/content/libr...es/F001688.pdf) In the fine print on page 5 it says that 1080 25p recording is actually recorded in 50i by a 2:2 pull down. Is that just a fancy name for field doubling? Does the PAL version of this camera actually record in "true" progressive 1080? or am I just reading this wrong? JB __________________ John Burkhart http://mynahmedia.com

April 7th, 2006, 02:00 AM	#3
John M Burkhart Regular Crew Join Date: Apr 2005 Location: Singapore Posts: 97	Thanks Barry for clearing that up. How is this different than the 1080 30p captured by the US versions? __________________ John Burkhart http://mynahmedia.com

April 7th, 2006, 01:58 AM	#2
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	It's true progressive imaging, not field doubling. It means that each frame gets printed onto two fields of video, so essentially the progressive frame is sliced into two halves; one gets recorded on one field, the other on the other field. Field Doubling would mean that the same information gets recorded onto both fields (or, even more accurately, that the information from the previous field gets repeated onto the odd field). In 1080/25p mode the HVX works using basically the same progressive-segmented frame technique as the CineAlta does. The codec is an interlaced codec, so the progressive information gets transported within the interlaced wrapper. But when editing, you'll be editing true progressive.

April 7th, 2006, 09:29 AM	#4
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	It's identical in method, the only difference is the actual frame rate. 1080/30P in the US version is recorded within a 1080/60i stream using 2:2 pulldown. 1080/25P in the EU version is recorded within a 1080/50i stream using 2:2 pulldown. It's the same thing.

April 10th, 2006, 02:59 AM	#6
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	No... fields are the full height of the picture, but alternating lines. So lines 0, 2, 4, 6, 8 etc are in one field, and 1, 3, 5, 7, 9 etc. are in the other field. In a field-doubling system, field 0 gets displayed on the even lines, and then instead of displaying field 1 on the odd lines, the system displays field 0 again on the odd lines. The result is that you get half the vertical resolution, but you get the temporal motion signature of a progressive-scan image. Sony cameras use field-doubling when you go into slow-shutter modes, for example.