Blu-ray Forum - View Single Post - 3D/2D Displays that support 3D & 2D & 24p at multiplies of the original frame rate

HDTV1080P · 06-19-2010, 09:34 PM

48HZ 3-D Frame Rate information

(All current home 3-D displays use 6:4 pulldown which is 3:2 pulldown judder for each eye)

The following Quotes taken from the following weblink
http://www.highdefdigest.com/news/show/Joshua_Zyber/HD_Advisor/Oh,_What_a_Night._HD_Advisor_Back_in_63/4915

"My understanding is that 3-D Blu-ray discs will be encoded with 1080p video at 24 frames per second, the same frame rate as traditional 2-D Blu-ray discs. The difference is that the 3-D version will be encoded with each frame at a resolution of 1920x2205 pixels. This equates to both the left eye and right eye views for each frame, stacked on top of one another, with some extra blanking pixels in between. (See the HD Guru web site for a graphic representation.)

These "packed" frames will be transmitted to the TV at 24 fps. At that point, the TV will decide how it wants to process them and display them on screen. Most models will unpack the frames into separate left and right frames at the traditional 1920x1080 resolution each, and then display them in sequence, much like interlacing. Those original 24 frames now become 48 frames per second. The TV will then multiply those 48 frames to its native display rate of either 120 Hz or 240 Hz.

Now, this is where things get tricky. If the TV is a 120 Hz model, that means that the left eye and right eye views must be displayed on screen at 60 frames per second respectively. Because 60 is not an even multiple of 24, the TV will apply 3:2 Pulldown to each of the original frames. Thus, you will lose the 24 fps cadence and may notice image judder.

At first, I assumed that a 240 Hz model TV would display the left and right views at 120 frames per second each, thus allowing the set to apply 5:5 Pulldown and maintain the original cadence through simple multiplication of frames. However, reader Lee pointed out that these sets actually insert black frames in between the video content frames. Therefore, the screen still only shows 60 video content frames per eye per second. Essentially, this means that there's no way to avoid 3:2 Pulldown with 3-D at the present time. Whether that might change in the future, I can't say."

06-19-2010, 09:34 PM	#899
HDTV1080P Blu-ray Champion Top contributor Member since:Jan 2007 Blu-ray reviews: 205	48HZ 3-D Frame Rate information (All current home 3-D displays use 6:4 pulldown which is 3:2 pulldown judder for each eye) The following Quotes taken from the following weblink http://www.highdefdigest.com/news/show/Joshua_Zyber/HD_Advisor/Oh,_What_a_Night._HD_Advisor_Back_in_63/4915 "My understanding is that 3-D Blu-ray discs will be encoded with 1080p video at 24 frames per second, the same frame rate as traditional 2-D Blu-ray discs. The difference is that the 3-D version will be encoded with each frame at a resolution of 1920x2205 pixels. This equates to both the left eye and right eye views for each frame, stacked on top of one another, with some extra blanking pixels in between. (See the HD Guru web site for a graphic representation.) These "packed" frames will be transmitted to the TV at 24 fps. At that point, the TV will decide how it wants to process them and display them on screen. Most models will unpack the frames into separate left and right frames at the traditional 1920x1080 resolution each, and then display them in sequence, much like interlacing. Those original 24 frames now become 48 frames per second. The TV will then multiply those 48 frames to its native display rate of either 120 Hz or 240 Hz. Now, this is where things get tricky. If the TV is a 120 Hz model, that means that the left eye and right eye views must be displayed on screen at 60 frames per second respectively. Because 60 is not an even multiple of 24, the TV will apply 3:2 Pulldown to each of the original frames. Thus, you will lose the 24 fps cadence and may notice image judder. At first, I assumed that a 240 Hz model TV would display the left and right views at 120 frames per second each, thus allowing the set to apply 5:5 Pulldown and maintain the original cadence through simple multiplication of frames. However, reader Lee pointed out that these sets actually insert black frames in between the video content frames. Therefore, the screen still only shows 60 video content frames per eye per second. Essentially, this means that there's no way to avoid 3:2 Pulldown with 3-D at the present time. Whether that might change in the future, I can't say."