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{{short description|High-fidelity digital video signal}} |
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'''Uncompressed video''', also called '''Clean HDMI''',<ref>[http://www.eoshd.com/content/9730/prores-vs-prores-a-first-look-at-uncompressed-hdmi-with-the-nikon-d5200-vs-the-blackmagic-cinema-camera ProRes vs ProRes – A first look at uncompressed HDMI with the Nikon D5200 vs the Blackmagic Cinema Camera] EOSHD</ref> is digital [[video]] information that has not been [[video compression|compressed]], or was not processed with compression on it when the video was captured directly via [[video capture]] (e.g. from a [[digital camera]]). It refers to the related [[data stream]] or the [[file format]] used in the video capture process. The purpose is to provide significantly higher quality video compared to [[lossy compression]],<ref>[http://msdn.microsoft.com/en-us/library/windows/desktop/dd743961(v=vs.85).aspx Using Uncompressed Audio and Video Streams] Microsoft</ref> allowing even [[Image scaling|resolution upscaling]]. |
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{{More citations needed|date=March 2023}} |
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'''Uncompressed video''' is [[digital video]] that either has never been [[video compression|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 [[Serial digital interface|SDI]]. Standards also exist for the carriage of uncompressed video over [[computer network]]s. |
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Although [[HD video]] capable cameras often include an HDMI interface for playback or [[live preview]], most cameras compress the signal substantially, using a lossy compression method such as [[MPEG]] or [[H.264]]. In the compression process, a substantial amount of the captured data is removed, which reduces visual quality. Editing video which has never been compressed allows a final result with better quality, and compression is then applied after all editing has been performed. In a true "Clean HDMI" implementation, the camera will either transmit the signal as it is captured "live," without the intermediate use of lossy compression, or the camera will capture, store, and transmit video in a RAW uncompressed format. |
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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 artifact]]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>[http://msdn.microsoft.com/en-us/library/windows/desktop/dd743961(v=vs.85).aspx Using Uncompressed Audio and Video Streams] Microsoft</ref> |
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This article focuses on HDMI, because it is the dominant digital video interface used in cameras today. However, uncompressed video can be transmitted over other types of baseband video interfaces, such as DVI, DisplayPort and SDI. Uncompressed video can also be copied from a storage card, if the video is captured in a RAW format. It is important to note that all video modes used in the [[HDMI]] transmit uncompressed digital video. The distinction here is that the video content is "clean," and has never been subjected to quality loss from compression. |
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Uncompressed video should not be confused with [[Raw image format|raw video]]. Raw video represents largely unprocessed data (e.g. without [[demosaicing]]) captured by an imaging device. |
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Currently ''uncompressed video'' is supported by [[Nikon#Digital single lens reflex cameras|Nikon DSLR]]s with the [[Expeed#Video processor|Expeed 3 (FR)]] and [[Expeed#Expeed 4|Expeed 4]] image/video processor (currently [[Nikon D4]], [[Nikon D4S|D4S]], [[Nikon D800|D800]]/[[Nikon D800E|D800E]], [[Nikon D810|D810]], [[Nikon D600|D600]], [[Nikon D610|D610]], [[Nikon D7100|D7100]], [[Nikon D7200|D7200]], [[Nikon D5200|D5200]], [[Nikon D5300|D5300]]) and [[Nikon D5500|D5500]]), the [[Canon EOS-1D C]], the [[Canon 5D Mark III]] with firmware 1.2.1, the [[Sony Alpha ILCE-6000|Sony A6000]] and professional video cameras (see [[list of video cameras supporting a raw format]]), which use proprietary '''raw video''' formats like [[CinemaDNG]] ([[open format]]) or [[ArriRaw]] with similarities to the [[raw image format]]. |
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== |
==Recording== |
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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. |
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Due to the high [[Data compression#Video|video compression]] in [[MPEG]] encoding, the [[video quality]] of ''uncompressed video'' delivers even more [[image resolution]], color quality, motion information, and [[Acutance|sharpness]] than the related [[Raw image format]]. |
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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 [[Computer program|program]] activity (e.g., [[background process]]es, [[virus scanner]]s) and asynchronous hardware interfaces (e.g., [[computer networks]]) may be disabled, and the [[Computer multitasking|process priority]] of the recording [[Real-time computing|realtime process]] may be increased, to avoid disruption of the recording process. |
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It has the further advantage of higher quality due to no [[motion blur]] (no [[motion compensation]]) and no [[compression artifact]]s. |
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HDMI, DVI and HD-SDI inputs are available as [[PCI Express]] (partly multi-channel) or [[ExpressCard]], [[USB 3.0]]<ref>[http://www.epiphan.com/products/compare-usb-video-grabbers/ Compare USB Video Grabbers] Epiphan</ref> and [[Thunderbolt (interface)|Thunderbolt]] interface<ref>[http://www.blackmagicdesign.com/products/intensity/ Intensity models] Blackmagic</ref><ref>[http://www.imperx.com/frame-grabbers/hd-sdi-express34 HD-SDI Express/34] Imperx</ref><ref>[http://www.deltacast.tv/Products/DELTA-hd-SDI-OEM-video-input-output-PCI-Express-card.asp OEM video card for 8-10-12-bit HD-SD SDI digital video to PCI Express] Deltacast</ref> also for [[2160p]] ([[4K resolution]]).<ref>[http://www.magewell.com/hardware?lang=en Capture Card Series] Magewell</ref><ref>[http://www.blackmagicdesign.com/products/decklink/models DeckLink models] Blackmagic</ref> |
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Currently there is no standardized ''uncompressed video'' file format except for HDMI, which uses the [[YCbCr]] and [[RGB]] formats listed below. This makes it necessary to store it best with a related description file about the used resolution and video mode. These files can be combined with [[lossless compression]] with the use of [[Comparison of file archivers|file archivers]]. |
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Software for recording uncompressed video is often supplied with suitable hardware or available for free e.g. [[Ingex]].<ref>[http://ingex.sourceforge.net/studio/ Ingex Studio - Multi-camera Tapeless Recording]</ref> |
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===Lossless video compression=== |
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[[List of codecs#Video codecs|Lossless video compression]] can be delivered with a variety of [[video codec]]s. In test some codecs performed an average compression of over factor 3.<ref>[http://compression.ru/video/codec_comparison/pdf/msu_lossless_codecs_comparison_2007_eng.pdf Lossless Codecs Comparison ‘2007] PDF</ref> |
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==Network transmission== |
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==Uncompressed video recording== |
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[[SMPTE 2022]] and [[SMPTE 2110|2110]] are standards for professional digital video over [[IP network]]s. SMPTE 2022 includes provisions for both compressed and uncompressed video formats. SMPTE 2110 carries uncompressed video, audio, and [[ancillary data]] as separate [[streaming media|streams]]. |
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Setting up the camera is often new especially for DSLR users.<ref>[http://www.bythom.com/hdmivideo.htm Capturing HDMI Video: A quick guide to getting the best video from a D4 or D800] Tom Hogan</ref><ref>[http://wolfcrow.com/blog/master-guide-to-rigging-a-nikon-d800-or-d800e-part-12/ Master Guide to Rigging a Nikon D800 or D800E for Video] Wolfcrow</ref> The built in [[video interface]] in cameras is mostly an [[HDMI]] or, in professional cameras, a [[Serial digital interface]] (SDI or HD-SDI); converters between both are available.<ref>[http://www.atomos.com/converters/ HD-SDI / HDMI digital video converters] Atomos</ref> |
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[[wireless network|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. |
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===Uncompressed video recorder=== |
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Portable recorders<ref>[http://www.blackmagicdesign.com/products/hyperdeckshuttle/ The world's smallest uncompressed video recorder] Blackmagic</ref> are an easy, reliable and complete solution for receiving and storing uncompressed video. Partly they receive uncompressed video, but only record [[Lossy compression|lossy compressed]] video, often in the lossy [[Apple ProRes 422]] or [[DNxHD codec]]s.<ref>[http://www.atomos.com/field-recorders/ Portable HD Field Recorder, Monitor, Playback And Playout Devices] Atomos</ref><ref>[http://www.sounddevices.com/products/video-recorders/ Video Recorders] Sound Devices</ref> Professional recorders support multiple channels of uncompressed HDMI, [[DVI]] or (HD-)SDI recording, but are limited by the total [[Data signaling rate|data rate]].<ref>[http://www.keisoku.co.jp/en/products/vw/recorder/ Video Disk Recorder] KEISOKU GIKEN</ref> |
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==Data rates== |
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===Recording to a computer=== |
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Recording to a computer enables low-cost to highest performance solutions for [[laptop]] or desktop computers, but the computer should be prepared as it must act like a [[real-time operating system]] (RTOS). Any other significant [[Computer program|program]] activity including [[background process]]es - for example not needed [[Windows NT startup process|Windows startup processes]] (use for example [[Autoruns]]) or [[Windows services]] (use [[Service Control Manager]]), including [[automatic update]]s or [[virus scanner]]s - may disrupt, distort or stop the video recording. Disconnection of not needed [[computer network]]s and increasing the [[Computer multitasking|process priority]] of the recording [[Real-time computing|realtime process]] often helps to use most of the computer speed. [[Hard disk drive]]s have to be fast [[solid-state drive]]s (SSDs) and/or [[RAID]] to be capable of the data-rate of [[HD video]]s and/or multiple channels. |
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Uncompressed video has a [[constant bitrate]] that is based on pixel representation, image resolution, and frame rate: |
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====Video capture interface==== |
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HDMI, DVI and HD-SDI inputs are available as [[PCI Express]] (partly multi-channel) or [[ExpressCard]], [[USB 3.0]] and [[Thunderbolt (interface)|Thunderbolt]] interface<ref>[http://www.blackmagicdesign.com/products/intensity/ Intensity models] Blackmagic</ref><ref>[http://www.imperx.com/frame-grabbers/hd-sdi-express34 HD-SDI Express/34] Imperx</ref><ref>[http://www.deltacast.tv/Products/DELTA-hd-SDI-OEM-video-input-output-PCI-Express-card.asp OEM video card for 8-10-12-bit HD-SD SDI digital video to PCI Express] Deltacast</ref> also for [[2160p]] ([[4K resolution]]).<ref>[http://www.magewell.com/hardware?lang=en Capture Card Series] Magewell</ref><ref>[http://www.blackmagicdesign.com/products/decklink/models DeckLink models] Blackmagic</ref> |
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:[[Data signaling rate|data rate]] = [[color depth]]{{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 [[Image resolution|resolution]] × horizontal resolution × [[refresh frequency]] {{Citation needed|date=January 2024}} |
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=====Wireless video interface===== |
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Most [[wireless network|Wireless interfaces]] like [[Wireless LAN]] (WLAN, [[Wi-Fi]]), [[WiDi]], [[Wireless Home Digital Interface]] (WHDI), can be used to transmit uncompressed digital video, but only with low resolutions, as even 1920x1080p@24 Hz requires 1.2 [[Gigabit per second|Gbit/s]] data rate exceeding for example [[IEEE 802.11ac]]. The [[WirelessHD]] interface, however, which uses a 60 GHz wireless link, can transmit uncompressed digital video. The [[Wireless Gigabit Alliance]] also aims to use a 60 GHz wireless link. However, any disruption or bandwidth decrease of the wireless connection will reduce quality, or even stop the video recording. |
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For example: |
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====Uncompressed video recording software==== |
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*16-bit, 480i @ 24 [[Frame rate|fps]]: 16 × {{resx|640|240}}{{efn|[[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.}} × 24 = 58.9 [[megabit per second|Mbit/s]] |
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Software for ''uncompressed video'' is often supplied with suitable hardware or available for free: [[Ingex]] ([[open source]]).<ref>[http://ingex.sourceforge.net/studio/ Ingex Studio - Multi-camera Tapeless Recording]</ref> |
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*24-bit, 480p @ 30 fps: 24 × {{resx|640|480}} × 30 = 221 Mbit/s. |
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*24-bit, 720p @ 30 fps: 24 × {{resx|1280|720}} × 30 = 663 Mbit/s. |
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*24-bit, 720p @ 60 fps: 24 × {{resx|1280|720}} × 60 = 1.32 [[gigabit per second|Gbit/s]] |
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*24-bit, 1080i @ 60 fps: 24 × {{resx|1920|540}} × 60 = 1.49 Gbit/s. |
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*24-bit, 1080p @ 60 fps: 24 × {{resx|1920|1080}} × 60 = 2.98 Gbit/s. |
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*24-bit, [[4K UHD]] @ 60 fps: 24 × {{resx|3840|2160}} × 60 = 11.9 Gbit/s. |
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*24-bit, 4K UHD @ 120 fps: 24 × {{resx|3840|2160}} × 120 = 23.8 Gbit/s. |
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*[[High color|48-bit]], [[DCI 4K]] @ 144 fps: 48 × {{resx|4096|2160}} × 144 = 61.1 Gbit/s. |
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The actual data rate may be higher because some transmission media for uncompressed video require defined [[Raster_scan#Video_timing|blanking intervals]], which effectively add unused pixels around the visible image. |
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==Storage and Data Rates for Uncompressed Video== |
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[[Constant bitrate]] formula: Uncompressed [[Data signaling rate|data rate]] = [[color depth]]s * vertical [[Image resolution|resolution]] * horizontal resolution * [[refresh frequency]] |
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;Examples |
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24bit @ 1080i @ 60fps :24*1920*1080*60/2=1.49 [[gigabit per second|Gbps]].<br /> |
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24bit @ 1080p @ 60fps :24*1920*1080*60=2.98 Gbit/s. |
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The storage and data rates for the widely used [[YCbCr]] [[Chroma subsampling#Types of subsampling|4:2:2 chroma subsampling]] uncompressed video are listed below: |
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;525 NTSC uncompressed |
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8 bit @ 720 x 486 @ 29.97fps = 20 [[Megabyte|MB]] per/sec, or 70 GB/hr.<br /> |
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10 bit @ 720 x 486 @ 29.97fps = 27 MB/s, or 94 GB/hr. |
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;625 PAL uncompressed |
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8 bit @ 720 x 576 @ 25fps = 20 MB/s, or 70 GB/hr.<br /> |
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10 bit @ 720 x 576 @ 25fps = 26 MB/s, or 93 GB/hr. |
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;720p HDTV uncompressed |
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8 bit @ 1280 x 720 @ 59.94fps = 105 MB/s, or 370 GB/hr.<br /> |
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10 bit @ 1280 x 720 @ 59.94fps = 140 MB/s, or 494 GB/hr. |
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;1080i and 1080p HDTV uncompressed |
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8 bit @ 1920 x 1080 @ 24fps = 95 MB/s, or 334 GB/hr.<br /> |
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10 bit @ 1920 x 1080 @ 24fps = 127 MB/s, or 445 GB/hr. |
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8 bit @ 1920 x 1080 @ 25fps = 99 MB/s, or 348 GB/hr.<br /> |
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10 bit @ 1920 x 1080 @ 25fps = 132 MB/s, or 463 GB/hr. |
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8 bit @ 1920 x 1080 @ 29.97fps = 119 MB/s, or 417 GB/hr.<br /> |
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10 bit @ 1920 x 1080 @ 29.97fps = 158 MB/s, or 556 GB/hr. |
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'''1080i and 1080p HDTV RGB (4:4:4) uncompressed'''<br /> |
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10 bit @ 1280 x 720p @ 60fps = 211 MB/s, or 742 GB/hr.<br /> |
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10 bit @ 1920 x 1080 @ 24fps = 190 MB/s, or 667 GB/hr.<br /> |
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10 bit @ 1920 x 1080 @ 50i = 198 MB/s, or 695 GB/hr.<br /> |
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10 bit @ 1920 x 1080 @ 60i = 237 MB/s, or 834 GB/hr. |
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==HDMI Specifications== |
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According to [[HDMI]] 1.3a Spec.<br /> |
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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. |
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Cameras mostly use the [[progressive segmented frame]] format: for example a 25p/30p [[progressive scan]] is transported in a 50i/60i [[interlaced]] format respectively, but with identical information: No [[deinterlacing]] should be used. |
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;Primary Video Format Timings |
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• 640x480p @ 59.94/60 Hz<br /> |
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• 1280x720p @ 59.94/60 Hz<br /> |
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• 1920x1080i @ 59.94/60 Hz<br /> |
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• 720x480p @ 59.94/60 Hz<br /> |
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• 720(1440)x480i @ 59.94/60 Hz<br /> |
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• 1280x720p @ 50 Hz<br /> |
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• 1920x1080i @ 50 Hz<br /> |
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• 720x576p @ 50 Hz<br /> |
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• 720(1440)x576i @ 50 Hz |
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;Secondary Video Format Timings |
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• 720(1440)x240p @ 59.94/60 Hz<br /> |
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• 2880x480i @ 59.94/60 Hz<br /> |
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• 2880x240p @ 59.94/60 Hz<br /> |
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• 1440x480p @ 59.94/60 Hz<br /> |
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• 1920x1080p @ 59.94/60 Hz<br /> |
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• 720(1440)x288p @ 50 Hz<br /> |
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• 2880x576i @ 50 Hz<br /> |
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• 2880x288p @ 50 Hz<br /> |
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• 1440x576p @ 50 Hz<br /> |
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• 1920x1080p @ 50 Hz<br /> |
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• 1920x1080p @ 23.98/24 Hz<br /> |
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• 1920x1080p @ 25 Hz<br /> |
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• 1920x1080p @ 29.97/30 Hz<br /> |
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• 2880x480p @ 59.94/60 Hz<br /> |
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• 2880x576p @ 50 Hz<br /> |
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• 1920x1080i (1250 total) @ 50 Hz<br /> |
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• 720(1440)x480i @ 119.88/120 Hz<br /> |
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• 720x480p @ 119.88/120 Hz<br /> |
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• 1920x1080i @ 119.88/120 Hz<br /> |
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• 1280x720p @ 119.88/120 Hz<br /> |
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• 720(1440)x480i @ 239.76/240 Hz<br /> |
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• 720x480p @ 239.76/240 Hz<br /> |
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• 720(1440)x576i @ 100 Hz<br /> |
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• 720x576p @ 100 Hz<br /> |
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• 1920x1080i @ 100 Hz<br /> |
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• 1280x720p @ 100 Hz<br /> |
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• 720(1440)x576i @ 200 Hz<br /> |
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• 720X576p @ 200 Hz |
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;Pixel Encodings and Color Depth |
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There are three different pixel encodings that may be sent across an HDMI cable: [[YCbCr]] [[Chroma subsampling#Types of subsampling|4:4:4 (chroma subsampling)]], [[YCbCr]] 4:2:2 and [[RGB]] 4:4:4. <br /> |
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There are four color depths supported: 24-, 30-, 36- and 48-bits per pixel. |
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In HDMI 2.0, it is possible to transmit 4:2:0 chroma subsampling, but only in 4K50 and 4K60 resolution. |
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==See also== |
==See also== |
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* [[List of video cameras supporting a raw format]] |
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* [[Data compression#Video|Data compression]] |
* [[Data compression#Video|Data compression]] |
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* [[Digital Picture Exchange|DPX]] and [[Material Exchange Format|MXF]] files – used in professional video files systems |
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* [[List of cameras supporting a raw format]] |
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* {{Section link|List of codecs|Lossless video compression}} |
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* [[Expeed#Video processor|Nikon Expeed Video processor]] |
* [[Expeed#Video processor|Nikon Expeed Video processor]] |
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* [[TIFF]] files – used in AV and professional video files systems |
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* [[Uncompressed audio]] |
* [[Uncompressed audio]] |
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* [[DPX]] and [[MXF]] files are used in professional video files systems. |
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==Notes== |
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* [[TIFF]] files are used in AV and professional video files systems. |
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{{notelist}} |
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==References== |
==References== |
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{{reflist |
{{reflist}} |
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==External links== |
==External links== |
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* [ |
* [https://toolstud.io/video/bitrate.php Video bitrate calculator] |
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* [http://www.creativeplanetnetwork.com/dcp/news/uncompressed-digital-video/45959 Uncompressed Digital Video] Creative Planet Network |
* [http://www.creativeplanetnetwork.com/dcp/news/uncompressed-digital-video/45959 Uncompressed Digital Video], Creative Planet Network |
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* [http://www.creativeplanetnetwork.com/dcp/news/uncompressed-vs-compressed/45625 Uncompressed vs. Compressed Video] Creative Planet Network |
* [http://www.creativeplanetnetwork.com/dcp/news/uncompressed-vs-compressed/45625 Uncompressed vs. Compressed Video], Creative Planet Network |
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* [http://wolfcrow.com/blog/master-guide-to-rigging-a-nikon-d800-or-d800e-part-12/ Master Guide to Rigging a Nikon D800 or D800E for Video] Wolfcrow |
* [http://wolfcrow.com/blog/master-guide-to-rigging-a-nikon-d800-or-d800e-part-12/ Master Guide to Rigging a Nikon D800 or D800E for Video], Wolfcrow |
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{{DSLR cameras with movie mode}} |
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{{VideoProcessing}} |
{{VideoProcessing}} |
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{{High-definition|state=collapsed}} |
{{High-definition|state=collapsed}} |
Latest revision as of 07:04, 1 May 2024
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.[1]
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[2] and Thunderbolt interface[3][4][5] also for 2160p (4K resolution).[6][7]
Software for recording uncompressed video is often supplied with suitable hardware or available for free e.g. Ingex.[8]
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[a] × vertical resolution × horizontal resolution × refresh frequency [citation needed]
For example:
- 16-bit, 480i @ 24 fps: 16 × 640 × 240[b] × 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
- Data compression
- DPX and MXF files – used in professional video files systems
- List of cameras supporting a raw format
- List of codecs § Lossless video compression
- Nikon Expeed Video processor
- TIFF files – used in AV and professional video files systems
- Uncompressed audio
Notes
- ^ 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.
- ^ 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
- ^ Using Uncompressed Audio and Video Streams Microsoft
- ^ Compare USB Video Grabbers Epiphan
- ^ Intensity models Blackmagic
- ^ HD-SDI Express/34 Imperx
- ^ OEM video card for 8-10-12-bit HD-SD SDI digital video to PCI Express Deltacast
- ^ Capture Card Series Magewell
- ^ DeckLink models Blackmagic
- ^ Ingex Studio - Multi-camera Tapeless Recording
External links
- Video bitrate calculator
- Uncompressed Digital Video, Creative Planet Network
- Uncompressed vs. Compressed Video, Creative Planet Network
- Master Guide to Rigging a Nikon D800 or D800E for Video, Wolfcrow