398:(e.g. analog or digital, standard def. or high def., etc.), and type of equipment available to the user, which is often related to budget constraints – as highest quality digital video equipment, and storage space, may be expensive. Effectively this means that any transcoding will involve some cumulative image loss, and hence the most practical solution insofar as minimizing loss of quality is for the original recording to be deemed the master copy, and for desired subsequent transcoded versions, which will often be in a different format and smaller file size, to be transcoded only from that master copy.
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options, which are either completely missing or very limited in PCM formats. These lossless formats can be transcoded to PCM formats or transcoded directly from one lossless format to another lossless format, without any loss in quality. They can be transcoded into a lossy format, but these copies
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is created. When sending the image to another phone, this high resolution image might be transcoded to a lower resolution image with fewer colors in order to better fit the target device's screen size and color limitations. This size and color reduction improves the user experience on the target
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that would be created if they were not, and because the huge storage demands being too cumbersome for the user otherwise. However, the amount of compression used at the recording stage can be highly variable, and is dependent on a number of factors, including the quality of images being recorded
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or uncompressed format, and then edit a copy of that master version, only converting to lossy formats if smaller file sized images are needed for final distribution. As with audio, transcoding from lossy format to another format of any type will result in a loss of quality.
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Real-time transcoding in a many-to-many way (any input format to any output format) is becoming a necessity to provide true search capability for any multimedia content on any mobile device, with over 500 million videos on the web and a plethora of mobile devices.
433:(MMS), which is the technology used to send or receive messages with media (image, sound, text and video) between mobile phones. For example, when a camera phone is used to take a digital picture, a high-quality image of usually at least 640x480
302:, and is used if the output resolution differs from the resolution of the media. On a powerful enough device, image scaling can be done on playback, but it can also be done by re-encoding, particularly as part of transrating (such as a
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and their capabilities. This diversity requires an intermediate state of content adaptation in order to make sure that the source content will adequately function on the target device to which it is sent.
267:, and make all edits on that copy, rather than repeatedly re-encoding it. Similarly, if encoding to a lossy format is required, it should be deferred until the data is finalised, e.g. after mastering.
489:, but onto a thin, dielectric target; the camera part reads the deposited charge pattern at a different scan rate from the back side of this target. The setup could also be used as a
178:) does not support the format or has limited storage capacity that mandates a reduced file size, or to convert incompatible or obsolete data to a better-supported or modern format.
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lossless format has better compression performance than other lossless coding technologies, and in many cases, JPEG2000 can compress images to half-size.
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will then not be able to be transcoded into another format of any kind (PCM, lossless, or lossy) without a subsequent loss of quality.
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In the analog video world, transcoding can be performed just while files are being searched, as well as for presentation. For example,
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can reduce the file size significantly while keeping the quality about the same. This is possible because most consumer cameras are
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is a process similar to transcoding in which files are coded to a lower bitrate without changing video formats; this can include
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Before the advent of semiconductors and integrated circuits, realtime resolution and frame rate transcoding between different
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Transcoding is a two-step process in which the original data is decoded to an intermediate uncompressed format (e.g.,
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197:(TB). That large size can increase the cost and difficulty of handling movie files. However, transcoding into a
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are cumulative, so transcoding causes a progressive loss of quality with each successive generation, known as
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Although transcoding can be found in many areas of content adaptation, it is commonly used in the area of
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device, and is sometimes the only way for content to be sent between different mobile devices.
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If one wishes to edit data in a compressed format (for instance, perform image editing on a
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image), one will generally decode it, edit it, then re-encode it. This re-encoding causes
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A frequency-domain video transcoder for dynamic bit-rate reduction of MPEG-2 bit streams
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by video files. The most common operation in this application is the transcoding of
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content adaptation. In this case, transcoding is a must, due to the diversity of
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One of the most popular technologies in which transcoding is used is the
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For users wanting to be able to re-encode audio into any format, and for
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The key drawback of transcoding in lossy formats is decreased quality.
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bitrate peeling as of 2008, the quality is inferior to re-encoding.
596:"Advancements in Compression and Transcoding: 2008 and Beyond",
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Five Steps for
Building Transcoding into Your Workflow whitepaper
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H.264/MPEG-4 AVC products and implementations § Transcoding
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Direct digital-to-digital conversion of one encoding to another
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IEEE Transactions on
Circuits and Systems for Video Technology
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616:"Why is Bit Rate Important When Converting Videos to MP3?"
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for video), which is then encoded into the target format.
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193:, but the data size of a two-hour movie is about 8
189:files have been widely used as a common format for
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598:Society of Motion Picture and Television Engineers
248:data in the same format, for a number of reasons:
381:users are advised to capture or save images in a
485:combination. The CRT part does not write onto a
298:Changing the picture size of video is known as
664:. General Electric Corporation. 10 April 1961
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712:Huifang Sun, Xuemin Chen, and Tihao Chiang,
639:: CS1 maint: numeric names: authors list (
614:Branson, Ryan (6 July 2015) (6 July 2015).
341:, it is best to retain a master copy in a
131:Learn how and when to remove this message
709:, vol. 8, no. 8, pp. 953-967, Dec. 1998.
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701:P. A. A. Assuncao and M. Ghanbari, "
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69:adding citations to reliable sources
441:Transcoding is extensively used by
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540:Comparison of DVD ripper software
306:image requiring a lower bitrate).
445:software to reduce the usage of
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729:IDC Report on Video Transcoding
154:data files, audio files (e.g.,
56:needs additional citations for
545:Comparison of video converters
310:One can also use formats with
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657:GEC 7828 Scan conversion tube
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681:General and cited references
477:standards was achieved by a
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528:Adaptive bitrate streaming
204:Transcoding is commonly a
32:Transcode (disambiguation)
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764:Video conversion software
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739:Transcoding White Papers
150:to another, such as for
754:Audio format converters
332:digital generation loss
261:digital generation loss
687:Federal Standard 1037C
620:Online Video Converter
280:sample rate conversion
518:Lossy data conversion
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328:Compression artifacts
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30:For other uses, see
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63:Please help
58:verification
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692:MIL-STD-188
659:data sheet"
483:camera tube
304:downsampled
300:transsizing
275:Transrating
232:for audio;
218:destructive
144:Transcoding
748:Categories
576:2018-01-14
534:Comparison
447:disk space
395:file sizes
91:newspapers
625:10 August
602:SMPTE-spm
551:Citations
424:real-time
371:meta data
345:(such as
322:Drawbacks
246:re-encode
195:terabytes
18:Transcode
668:21 April
635:cite web
502:Concepts
497:See also
487:phosphor
461:format.
288:Video CD
199:JPEG2000
176:workflow
148:encoding
491:genlock
469:History
355:WavPack
353:, TTA,
286:onto a
252:Editing
224:Process
166:(e.g.,
105:scholar
705:", in
455:MPEG-4
451:MPEG-2
435:pixels
365:, and
316:Vorbis
183:Cineon
162:), or
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662:(PDF)
459:H.264
402:Usage
168:UTF-8
152:video
112:JSTOR
98:books
670:2017
641:link
627:2015
389:For
377:For
367:AIFF
351:ALAC
347:FLAC
265:once
257:JPEG
185:and
84:news
34:and
479:CRT
457:or
383:raw
363:WAV
359:PCM
284:DVD
234:YUV
230:PCM
187:DPX
160:WAV
156:MP3
67:by
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