*Section 1 - Introduction

The standard methodology for noting the type of video being used is broken up into three major parts.

An example of the standard notation is:

1080p24

1.Raster - The number 1080 is the number of active lines in the raster.

In this case it indicates a standard raster size of 1920x1080

The standard raster sizes are 720x486 (480) (SD), 720x576 (576) (SD), 1280x720 (720) (HD), and 1920x1080 (1080) (HD).

2.Frame type - The letter "p" in the middle indicates the frame type.

In this case it indicates a progressive frame

The standard frame types are p - progressive, i - interlaced, and psf - progressive segmented frame

Notes:

1.A "psf" frame is simply just a progressive frame that just happens to come down the wire as two interlaced fields. This is done to get frame rates such as 24fps above the human flicker perception frequency (i.e. the actual refresh rate becomes 48Hz instead of 24Hz).

2. When an interlaced type is given the following frame rate number actually describes the field rate (or double the frame rate).

3.Frame/field rate - The number 24 in the actual frame/field rate of the video.

In this case the video runs at 24 frames per second

The standard frame/field rates are: 23.98, 24, 25, 29.97, 30, 50, 59.94, and 60

Note: You may also see the frame rates noted in terms of their timebase, especially if it is a 1/1.001 timebase. So for instance, 1080p23.98 would become 1080p24(/1.001).

*Section 2 - Raster/framerate support matrix

This table lists the common supported raster/framerate pairings.

While the various video standards make legal most, if not all, of these pairings only a select few are used by the industry.

The completely unsupported pairings have been removed for simplicity.

720x486 720x576 1280x720 1920x1080

23.98p Note 1 Note 2 YES

24p Note 1 Note 2 YES

25p Note 3 YES

29.97p Note 3 YES

30p YES

59.94p YES

60p YES

50i YES YES

59.94i YES YES

60i YES

Notes:

1.To transfer 24p or 23.98p material to the NTSC raster/framerate (480i59.97) a process known as 2:3 pulldown is used.

2.To transfer 24p or 23.98p material to the PAL raster/framerate (576i50) the original 24fps material is run at 25fps.

3.Certain NTSC/PAL cameras will capture a progressive frame and send it down the wire as segmented progressive.

*Section 3 - Colorspaces

While the specs only call for one colorspace down the wire (10bit YUV) it is worth noting that the video frames are often translated into other bit depths and/or colorspaces to work more easily with a particular format. Here are the common colorspaces:

*10bit YUV (4:2:2)

This format is the native wire colorspace format for both the standard and high definition SDI (video serial digital interface) protocols (SMPTE 259M and SMPTE 292M respectively). When stored on disk it is normally packed in such a way that conserves storage space, but makes working with it require an unpacking first. Luckily most modern hardware that work with this format will also handle the packed data directly. It is also worth noting that the two SD formats use a slightly different colorspace than the two HD formats.

*8bit YUV (4:2:2)

This is the 8bit version of the format described above. It is quite simply a 10bit YUV with the last two least significant bits chopped off. This format does not require any special packing as 8bits tend to line up quite well in a computer, however there are several variants of this colorspace that use different byte ordering.

*10bit RGB

This is the largest of all the colorspaces listed here, but is also the one that retains the most video information. The new SMPTE 372M spec actually allows for the colorspace to be transmitted via dual channel HD-SDI. The format comes in several variants and usually requires a moderate amount of unpacking to use.

*8bit RGB(A)

If ever there was a work horse of the computer graphics industry, this would be the one. While this format eliminated two bits of precision, it is quite portable and widely accepted. It requires more space than it's YUV counterpart, but also retains more video information. There are quite a few variations on this colorspace, mostly having to do with byte ordering. This document assumes a 32bit aligned pixel that may or may not have an alpha channel. This format requires no unpacking, but may be packed to eliminate the alpha channel if not used.

*Section 3 - Raster/Colorspace frame sizes

Here is a matrix of frame sizes (in bytes) of all the standard raster and colorspaces.

10bit YUV

(4:2:2) 8bit YUV

(4:2:2) 10bit RGB /

8bit RGBA 8bit RGB

720x486 933120 699840 1399680 1049760

720x576 1105920 829440 1658880 1244160

1280x720 2488320 1843200 3686400 2764800

1920x1080 5529600 4147200 8294400 6220800

*Section 4 - 10bit 4:2:2 YUV (packed) datarates

Here are the datarates of the various raster/framerates in the 10bit YUV colorspace. If you are using these figures to get an idea of needed disk bandwidth you will need to account for file system overhead. (so your needed bandwidth will be even higher than listed).

MB/S GB/HR

480i60 (@ 24fps) 22.395 80.622

480i60 27.994 100.778

576i50 27.648 99.533

720p60 149.299 537.476

1080p24 132.710 477.756

1080p25/i50 138.240 497.664

1080p30/i60 165.888 597.197

*Section 5 - 8bit 4:2:2 YUV datarates

Here are the datarates of the various raster/framerates in the 8bit YUV colorspace. If you are using these figures to get an idea of needed disk bandwidth you will need to account for file system overhead. (so your needed bandwidth will be even higher than listed).

MB/S GB/HR

480i60 (@ 24fps) 16.789 60.440

480i60 20.995 75.582

576i50 20.736 74.650

720p60 110.592 398.131

1080p24 99.533 358.319

1080p25/i50 103.680 373.248

1080p30/i60 124.416 447.898

*Section 6 - 10bit RGB / 8bit RGBA datarates

Here are the datarates of the various raster/framerates in the 10bit RGB or 8bit RGBA colorspaces. If you are using these figures to get an idea of needed disk bandwidth you will need to account for file system overhead. (so your needed bandwidth will be even higher than listed).

MB/S GB/HR

480i60 (@ 24fps) 33.592 120.946

480i60 41.990 151.164

576i50 41.472 149.299

720p60 221.184 796.262

1080p24 199.066 716.638

1080p25/i50 207.360 746.496

1080p30/i60 248.832 895.795

*Section 7 - 8bit RGB datarates

Here are the datarates of the various raster/framerates in the 8bit RGB colorspace. If you are using these figures to get an idea of needed disk bandwidth you will need to account for file system overhead. (so your needed bandwidth will be even higher than listed).

MB/S GB/HR

480i60 (@ 24fps) 25.194 90.698

480i60 31.493 113.375

576i50 31.104 111.974

720p60 165.888 597.197

1080p24 149.299 537.476

1080p25/i50 155.520 559.872

1080p30/i60 186.624 671.846

*Section 8 - Important video standards

Here is a list of key video standards:

*SMPTE 260M - This standard defines the older 1035 active line HD format. (still a 1920x1080 raster)

*SMPTE 274M - This standard defines the 1920x1080 high definition raster and it's supported frame rates.

*SMPTE 295M - This standard defines the 1920x1080i50 (PAL) high definition raster and frame rate.

*SMPTE 296M - This standard defines the 1280x720 high definition raster and it's supported frame rates.

*SMPTE 259M - This standard defines the 270 Mbit/s SDI wire transmission protocol for standard definition video.

*SMPTE 292M - This standard defines the 1.485 Gbit/s SDI wire transmission protocol for high definition video.

*ITU-R BT.601 - This standard covers the YCrCb (YUV) colorspace of standard definition video.

*ITU-R BT.709 - This standard covers the YPrPb (YUV) colorspace of high definition video.

Note: 1 MB = 1000000 bytes, 1 GB = 1000 MBs

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