Misplaced Pages

Uncompressed video: Difference between revisions

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Browse history interactively← Previous editContent deleted Content addedVisualWikitext
Revision as of 17:12, 6 January 2017 editLambtron (talk | contribs)Extended confirmed users11,112 edits →Recording to a computer: clarifiction← Previous edit Latest revision as of 17:37, 19 November 2024 edit undoKvng (talk | contribs)Extended confirmed users, New page reviewers108,347 edits Reverted good faith edits by 2A0D:B201:3010:8CFB:57F9:B498:1A99:38D7 (talk): Unexplained deletion by anonTags: Twinkle Undo 
(70 intermediate revisions by 38 users not shown)
Line 1: Line 1:
{{short description|High-fidelity digital video signal}}
'''Uncompressed video''' is ] that either has never been ] or was generated by decompressing previously compressed digital video. It is commonly used by video cameras, video recording devices (including general purpose computers), and in video processors that perform functions such as image resizing, image rotation and text and graphics overlay. It is conveyed over various types of baseband digital video interfaces, such as ], ], ] and ].
{{More citations needed|date=March 2023}}


'''Uncompressed video''' is ] that either has never been ] or was generated by decompressing previously compressed digital video. It is commonly used by video cameras, video monitors, video recording devices (including general-purpose computers), and in video processors that perform functions such as image resizing, image rotation, ], and text and graphics overlay. It is conveyed over various types of baseband digital video interfaces, such as ], ], ] and ]. Standards also exist for the carriage of uncompressed video over ]s.
Some ] cameras output uncompressed video, whereas others compress the video using a lossy compression method such as ] or ]. In the compression process, some of the video information is removed, which creates ]s and reduces the quality of the video when decompressed. When editing video, it is preferred to work with video that has never been compressed as this maintains the best possible quality, with compression performed after completion of editing.<ref> Microsoft</ref>

Some ] cameras output uncompressed video, whereas others compress the video using a lossy compression method such as ] or ]. In any lossy compression process, some of the video information is removed, which creates ]s and reduces the quality of the resulting decompressed video. When editing video, it is preferred to work with video that has never been compressed (or was losslessly compressed) as this maintains the best possible quality, with compression performed after completion of editing.<ref> Microsoft</ref>

Uncompressed video should not be confused with ]. Raw video represents largely unprocessed data (e.g. without ]) captured by an imaging device.


==Recording== ==Recording==
A standalone video recorder is a device that receives uncompressed video and stores it in either uncompressed or compressed form. These devices typically have a video output that can be used to monitor or playback recorded video. When playing back compressed video, the compressed video is uncompressed by the device before being output. Such devices may also have a communication interface, such as Ethernet or USB, which can used to exchange video files with an external computer, and in some cases control the recorder from an external computer as well.
===Standalone recorders===
A standalone video recorder is a device that receives uncompressed video and stores it in either uncompressed or compressed form. These devices typically have a video output which can be used to monitor or playback recorded video.
When playing back compressed video, the compressed video is uncompressed by the device before being output. Such devices may also have a communication interface, such as Ethernet or USB, which can used to exchange video files with an external computer, and in some cases control the recorder from an external computer as well.


Recording to a computer is a relatively inexpensive alternative to implementing a digital video recorder, but the computer and its video storage device (e.g., ], ]) must be fast enough to keep up with the high video data rate, which in some cases may be ] or multiple video sources, or both. Due to the extreme computational and storage system performance demands of real-time video processing, other unnecessary ] activity (e.g., ]es, ]s) and asynchronous hardware interfaces (e.g., ]) may be disabled, and the ] of the recording ] may be increased, to avoid disruption of the recording process.
===Recording to a computer===
Recording to a computer is a relatively inexpensive way to implement a digital video recorder, but the computer and its video storage device (e.g., ], ]) must be fast enough to keep up with the high video data rate, which in some cases may be ] or multiple video sources, or both. Due to the extreme computational and storage system performance demands of real-time video processing, other unnecessary ] activity (e.g., ]es, ]s) and asynchronous hardware interfaces (e.g., ]) may be disabled, and the ] of the recording ] may be increased, to avoid disruption of the recording process.


====Video capture interface====
HDMI, DVI and HD-SDI inputs are available as ] (partly multi-channel) or ], ]<ref> Epiphan</ref> and ] interface<ref> Blackmagic</ref><ref> Imperx</ref><ref> Deltacast</ref> also for ] (]).<ref> Magewell</ref><ref> Blackmagic</ref> HDMI, DVI and HD-SDI inputs are available as ] (partly multi-channel) or ], ]<ref> Epiphan</ref> and ] interface<ref> Blackmagic</ref><ref> Imperx</ref><ref> Deltacast</ref> also for ] (]).<ref> Magewell</ref><ref> Blackmagic</ref>


Software for recording uncompressed video is often supplied with suitable hardware or available for free e.g. ].<ref></ref>
====Software====
Software for ''uncompressed video'' is often supplied with suitable hardware or available for free: ] (]).<ref></ref>


==Wireless transmission== ==Network transmission==
] and ] are standards for professional digital video over ]s. SMPTE 2022 includes provisions for both compressed and uncompressed video formats. SMPTE 2110 carries uncompressed video, audio, and ] as separate ].
] such as ] (WLAN, ]), ], ] (WHDI), can be used to transmit uncompressed digital video at lower resolutions, but typically not at HD resolutions as even 1920x1080p@24&nbsp;Hz requires a 1.2&nbsp;] data rate, which exceeds the maximum bandwidth of these interfaces (e.g., ]). The ] interface, however, which uses a 60&nbsp;GHz wireless link, can transmit uncompressed digital video. The ] also aims to use a 60&nbsp;GHz wireless link. However, any disruption or bandwidth decrease of the wireless connection will reduce quality, or even stop the video recording.

] such as ] (WLAN, ]), ], and ] can be used to transmit uncompressed standard definition (SD) video but not HD video because the HD bit rates would exceed the network bandwidth. HD can be transmitted using higher-speed interfaces such as ] and ]. In all cases, when video is conveyed over a network, communication disruptions or diminished bandwidth can corrupt the video or prevent its transmission.


==Data rates== ==Data rates==
Line 24: Line 26:
Uncompressed video has a ] that is based on pixel representation, image resolution, and frame rate: Uncompressed video has a ] that is based on pixel representation, image resolution, and frame rate:


:] = ] * vertical ] * horizontal resolution * ] :] = ]{{efn|Most of the time color depth can be calculated as 3 × single color depth. For example, values of a single color can be represented with a range from 0 to 255 (8 bits) which gives a total color depth as 3 × 8 <nowiki>=</nowiki> 24.}} × vertical ] × horizontal resolution × ] {{Citation needed|date=January 2024}}


For example: For example:
*16-bit, 480i @ 24 ]: 16 × {{resx|640|240}}{{efn|] formats transmit every other line, half the picture content, per field period. Two fields are required for a full frame so the vertical resolution is halved in this calculation.}} × 24 = 58.9 ]
*24-bit, 1080i @ 60 ]: 24 × 1920x1080 × 60/2 = 1.39 ]
*24-bit, 1080p @ 60 fps: 24 × 1920x1080 × 60 = 2.78 Gbit/s. *24-bit, 480p @ 30 fps: 24 × {{resx|640|480}} × 30 = 221&nbsp;Mbit/s.
*24-bit, 720p @ 30 fps: 24 × {{resx|1280|720}} × 30 = 663&nbsp;Mbit/s.
*24-bit, 720p @ 60 fps: 24 × {{resx|1280|720}} × 60 = 1.32 ]
*24-bit, 1080i @ 60 fps: 24 × {{resx|1920|540}} × 60 = 1.49&nbsp;Gbit/s.
*24-bit, 1080p @ 60 fps: 24 × {{resx|1920|1080}} × 60 = 2.98&nbsp;Gbit/s.
*24-bit, ] @ 60 fps: 24 × {{resx|3840|2160}} × 60 = 11.9&nbsp;Gbit/s.
*24-bit, 4K UHD @ 120 fps: 24 × {{resx|3840|2160}} × 120 = 23.8&nbsp;Gbit/s.
*], ] @ 144 fps: 48 × {{resx|4096|2160}} × 144 = 61.1&nbsp;Gbit/s.


The actual data rate may be higher because some transmission media for uncompressed video require defined ], which effectively add unused pixels around the visible image.
===4:2:2 format===

The data rates and storage requirements for the widely used ] ] format are listed below:

;NTSC
*8-bit, 720x486 @ 29.97 fps = 20 ]/s, or 70 GB/h
*10-bit, 720x486 @ 29.97 fps = 27 MB/s, or 94 GB/h

;PAL
*8-bit, 720x576 @ 25 fps = 20 MB/s, or 70 GB/h
*10-bit, 720x576 @ 25 fps = 26 MB/s, or 93 GB/h

;720p
*8-bit, 1280x720 @ 59.94 fps = 105 MB/s, or 370 GB/h
*10-bit, 1280x720 @ 59.94 fps = 140 MB/s, or 494 GB/h

;1080i and 1080p
*8-bit, 1920x1080 @ 24 fps = 95 MB/s, or 334 GB/h
*10-bit, 1920x1080 @ 24 fps = 127 MB/s, or 445 GB/h

*8-bit, 1920x1080 @ 25 fps = 99 MB/s, or 348 GB/h
*10-bit, 1920x1080 @ 25 fps = 132 MB/s, or 463 GB/h

*8-bit, 1920x1080 @ 29.97 fps = 119 MB/s, or 417 GB/h
*10-bit, 1920x1080 @ 29.97 fps = 158 MB/s, or 556 GB/h

'''1080i and 1080p RGB (4:4:4)'''
*10-bit, 1280x720p @ 60 fps = 211 MB/s, or 742 GB/h
*10-bit, 1920x1080 @ 24 fps = 190 MB/s, or 667 GB/h
*10-bit, 1920x1080 @ 50i = 198 MB/s, or 695 GB/h
*10-bit, 1920x1080 @ 60i = 237 MB/s, or 834 GB/h

==HDMI specifications==
According to ] 1.3a spec.<br />
Detailed timing is found in CEA-861-D or a later version of CEA-861 for the following video format timings. HDMI 2.0 supports higher resolutions, which are defined in CEA-861-F.

Cameras mostly use the ] format: for example a 25p/30p ] is transported in a 50i/60i ] format respectively, but with identical information: No ] should be used.

;Primary video format timings
• 640x480p @ 59.94/60&nbsp;Hz<br />
• 1280x720p @ 59.94/60&nbsp;Hz<br />
• 1920x1080i @ 59.94/60&nbsp;Hz<br />
• 720x480p @ 59.94/60&nbsp;Hz<br />
• 720(1440)x480i @ 59.94/60&nbsp;Hz<br />
• 1280x720p @ 50&nbsp;Hz<br />
• 1920x1080i @ 50&nbsp;Hz<br />
• 720x576p @ 50&nbsp;Hz<br />
• 720(1440)x576i @ 50&nbsp;Hz

;Secondary video format timings
• 720(1440)x240p @ 59.94/60&nbsp;Hz<br />
• 2880x480i @ 59.94/60&nbsp;Hz<br />
• 2880x240p @ 59.94/60&nbsp;Hz<br />
• 1440x480p @ 59.94/60&nbsp;Hz<br />
• 1920x1080p @ 59.94/60&nbsp;Hz<br />
• 720(1440)x288p @ 50&nbsp;Hz<br />
• 2880x576i @ 50&nbsp;Hz<br />
• 2880x288p @ 50&nbsp;Hz<br />
• 1440x576p @ 50&nbsp;Hz<br />
• 1920x1080p @ 50&nbsp;Hz<br />
• 1920x1080p @ 23.98/24&nbsp;Hz<br />
• 1920x1080p @ 25&nbsp;Hz<br />
• 1920x1080p @ 29.97/30&nbsp;Hz<br />
• 2880x480p @ 59.94/60&nbsp;Hz<br />
• 2880x576p @ 50&nbsp;Hz<br />
• 1920x1080i (1250 total) @ 50&nbsp;Hz<br />
• 720(1440)x480i @ 119.88/120&nbsp;Hz<br />
• 720x480p @ 119.88/120&nbsp;Hz<br />
• 1920x1080i @ 119.88/120&nbsp;Hz<br />
• 1280x720p @ 119.88/120&nbsp;Hz<br />
• 720(1440)x480i @ 239.76/240&nbsp;Hz<br />
• 720x480p @ 239.76/240&nbsp;Hz<br />
• 720(1440)x576i @ 100&nbsp;Hz<br />
• 720x576p @ 100&nbsp;Hz<br />
• 1920x1080i @ 100&nbsp;Hz<br />
• 1280x720p @ 100&nbsp;Hz<br />
• 720(1440)x576i @ 200&nbsp;Hz<br />
• 720X576p @ 200&nbsp;Hz

;Pixel encodings and color depth
There are three different pixel encodings that may be sent across an HDMI cable: ] ], ] 4:2:2 and ] 4:4:4. <br />
There are four color depths supported: 24-, 30-, 36- and 48-bits per pixel.
In HDMI 2.0, it is possible to transmit 4:2:0 chroma subsampling, but only in 4K50 and 4K60 resolution.


==See also== ==See also==
* ]
* ] * ]
* ] and ] files – used in professional video files systems
* ]
* {{Section link|List of codecs|Lossless video compression}}
* ] * ]
* ]
* ] and ] files – used in professional video files systems
* ] files – used in AV and professional video files systems * ] files – used in AV and professional video files systems
* ]

==Notes==
{{notelist}}


==References== ==References==
{{reflist|30em}} {{reflist}}


==External links== ==External links==
* Forret *
* Creative Planet Network * , Creative Planet Network
* Creative Planet Network * , Creative Planet Network
* Wolfcrow * , Wolfcrow


{{DSLR cameras with movie mode}}
{{VideoProcessing}} {{VideoProcessing}}
{{High-definition|state=collapsed}} {{High-definition|state=collapsed}}

Latest revision as of 17:37, 19 November 2024

High-fidelity digital video signal
This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.
Find sources: "Uncompressed video" – news · newspapers · books · scholar · JSTOR (March 2023) (Learn how and when to remove this message)

Uncompressed video is digital video that either has never been compressed or was generated by decompressing previously compressed digital video. It is commonly used by video cameras, video monitors, video recording devices (including general-purpose computers), and in video processors that perform functions such as image resizing, image rotation, deinterlacing, and text and graphics overlay. It is conveyed over various types of baseband digital video interfaces, such as HDMI, DVI, DisplayPort and SDI. Standards also exist for the carriage of uncompressed video over computer networks.

Some HD video cameras output uncompressed video, whereas others compress the video using a lossy compression method such as MPEG or H.264. In any lossy compression process, some of the video information is removed, which creates compression artifacts and reduces the quality of the resulting decompressed video. When editing video, it is preferred to work with video that has never been compressed (or was losslessly compressed) as this maintains the best possible quality, with compression performed after completion of editing.

Uncompressed video should not be confused with raw video. Raw video represents largely unprocessed data (e.g. without demosaicing) captured by an imaging device.

Recording

A standalone video recorder is a device that receives uncompressed video and stores it in either uncompressed or compressed form. These devices typically have a video output that can be used to monitor or playback recorded video. When playing back compressed video, the compressed video is uncompressed by the device before being output. Such devices may also have a communication interface, such as Ethernet or USB, which can used to exchange video files with an external computer, and in some cases control the recorder from an external computer as well.

Recording to a computer is a relatively inexpensive alternative to implementing a digital video recorder, but the computer and its video storage device (e.g., solid-state drive, RAID) must be fast enough to keep up with the high video data rate, which in some cases may be HD video or multiple video sources, or both. Due to the extreme computational and storage system performance demands of real-time video processing, other unnecessary program activity (e.g., background processes, virus scanners) and asynchronous hardware interfaces (e.g., computer networks) may be disabled, and the process priority of the recording realtime process may be increased, to avoid disruption of the recording process.

HDMI, DVI and HD-SDI inputs are available as PCI Express (partly multi-channel) or ExpressCard, USB 3.0 and Thunderbolt interface also for 2160p (4K resolution).

Software for recording uncompressed video is often supplied with suitable hardware or available for free e.g. Ingex.

Network transmission

SMPTE 2022 and 2110 are standards for professional digital video over IP networks. SMPTE 2022 includes provisions for both compressed and uncompressed video formats. SMPTE 2110 carries uncompressed video, audio, and ancillary data as separate streams.

Wireless interfaces such as Wireless LAN (WLAN, Wi-Fi), WiDi, and Wireless Home Digital Interface can be used to transmit uncompressed standard definition (SD) video but not HD video because the HD bit rates would exceed the network bandwidth. HD can be transmitted using higher-speed interfaces such as WirelessHD and WiGig. In all cases, when video is conveyed over a network, communication disruptions or diminished bandwidth can corrupt the video or prevent its transmission.

Data rates

Uncompressed video has a constant bitrate that is based on pixel representation, image resolution, and frame rate:

data rate = color depth × vertical resolution × horizontal resolution × refresh frequency

For example:

  • 16-bit, 480i @ 24 fps: 16 × 640 × 240 × 24 = 58.9 Mbit/s
  • 24-bit, 480p @ 30 fps: 24 × 640 × 480 × 30 = 221 Mbit/s.
  • 24-bit, 720p @ 30 fps: 24 × 1280 × 720 × 30 = 663 Mbit/s.
  • 24-bit, 720p @ 60 fps: 24 × 1280 × 720 × 60 = 1.32 Gbit/s
  • 24-bit, 1080i @ 60 fps: 24 × 1920 × 540 × 60 = 1.49 Gbit/s.
  • 24-bit, 1080p @ 60 fps: 24 × 1920 × 1080 × 60 = 2.98 Gbit/s.
  • 24-bit, 4K UHD @ 60 fps: 24 × 3840 × 2160 × 60 = 11.9 Gbit/s.
  • 24-bit, 4K UHD @ 120 fps: 24 × 3840 × 2160 × 120 = 23.8 Gbit/s.
  • 48-bit, DCI 4K @ 144 fps: 48 × 4096 × 2160 × 144 = 61.1 Gbit/s.

The actual data rate may be higher because some transmission media for uncompressed video require defined blanking intervals, which effectively add unused pixels around the visible image.

See also

Notes

  1. Most of the time color depth can be calculated as 3 × single color depth. For example, values of a single color can be represented with a range from 0 to 255 (8 bits) which gives a total color depth as 3 × 8 = 24.
  2. Interlaced video formats transmit every other line, half the picture content, per field period. Two fields are required for a full frame so the vertical resolution is halved in this calculation.

References

  1. Using Uncompressed Audio and Video Streams Microsoft
  2. Compare USB Video Grabbers Epiphan
  3. Intensity models Blackmagic
  4. HD-SDI Express/34 Imperx
  5. OEM video card for 8-10-12-bit HD-SD SDI digital video to PCI Express Deltacast
  6. Capture Card Series Magewell
  7. DeckLink models Blackmagic
  8. Ingex Studio - Multi-camera Tapeless Recording

External links

Video processing
Post-processing
Special processing
High-definition (HD)
Concepts
Resolutions
Analog broadcast
(All defunct)
Digital broadcast
Audio
Filming and storage
HD media and
compression
Connectors
Deployments
Categories: