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BitJazz
SheerVideo FAQ
Formats: Precisions
Does SheerVideo support 10-bit channels?
Does SheerVideo support 16-bit channels?
Does SheerVideo support 8-bit channels?
 Does SheerVideo support 8-bit channels?
Yes, SheerVideo codecs currently supports real-time lossless encoding and decoding of 8-bit data:
RGB[A] 8b, Y'CbCr[A] 8bv 4:4:4[:4], Y'CbCr[A] 8bu 4:4:4[:4], Y'CbCr[A] 8bv 4:2:2[:4], and Y'CbCr 8bw 4:2:2,
both progressive and interlaced, at all resolutions and frame rates, on both Mac and Windows.
SheerVideo supports the 8-bit RGB[A] 8b pixel formats
'ARGB', 'ABGR', 'RGBA', 'BGRA', 'RGB ', and 'BGR ';
the 8-bit Y'CbCr[A] 8bu|v 4:4:4[:4] pixel formats
'r408', 'v408', and 'VUYA';
the 8-bit Y'CbCr[A] 8bv 4:2:2[:4] pixel formats
'2vuy' and 'yuvs';
and the 8-bit Y'CbCr 8bw 4:2:2 pixel format
'yuvu' or 'yuv2'.
The specific Sheer codec corresponding to 8-bit RGB[A] 8b is
which encodes from and decodes to RGB[A] 8b losslessly in real time.
Sheer RGB[A] 10b also encodes from and decodes to RGB[A] 10b losslessly in real time.
Sheer Y'CbCr[A] 10bv 4:4:4[:4] also encodes from and decodes to RGB[A] 8b losslessly using Synchromy, though not always in real time.
Sheer Y'CbCr[A] 8bv 4:4:4[:4], Sheer Y'CbCr[A] 10bv 4:2:2[:4], and Sheer Y'CbCr[A] 8bv 4:2:2[:4] also encode from and decode to RGB[A] 8b,
though not losslessly and not always in real time.
The generic Sheer encoder encodes RGB[A] 8b as Sheer RGB[A] 8b.
The specific Sheer codec corresponding to 8-bit Y'CbCr[A] 8bv 4:4:4[:4] is
- Sheer Y'CbCr[A] 8bv 4:4:4[:4]
which encodes from and decodes to Y'CbCr[A] 10bv 4:4:4[:4] losslessly in real time.
Sheer Y'CbCr[A] 10bv 4:4:4[:4] also encodes from and decodes to Y'CbCr[A] 8bv 4:4:4[:4] losslessly in real time.
Sheer RGB[A] 10b also encodes from and decodes back to Y'CbCr[A] 8bv 4:4:4[:4] losslessly (except for out-of-range colors) using Synchromy,
though not always in real time.
Sheer RGB[A] 8b, Sheer Y'CbCr[A] 10bv 4:2:2[:4], and Sheer Y'CbCr[A] 8bv 4:2:2[:4] also encode from and decode to Y'CbCr[A] 8bv 4:4:4[:4],
though not losslessly and not always in real time.
The generic Sheer encoder encodes Y'CbCr[A] 8bv 4:4:4[:4] as Sheer Y'CbCr[A] 8bv 4:4:4[:4].
The specific Sheer codec corresponding to 8-bit Y'CbCr[A] 8bu 4:4:4[:4] is
- Sheer Y'CbCr[A] 8bu 4:4:4[:4]
an unbiassed variant of the Sheer Y'CbCr[A] 8bv 4:4:4[:4] codec,
which encodes from and decodes to Y'CbCr[A] 8bu 4:4:4[:4] losslessly in real time.
Sheer Y'CbCr[A] 10bv 4:4:4[:4] also encodes from and decodes to this data format losslessly (except for out-of-range colors) in real time.
Sheer RGB[A] 10b also encodes from and decodes to Y'CbCr[A] 8bu 4:4:4[:4] losslessly (except for out-of-range colors) using Synchromy, but not always in real time.
Sheer RGB[A] 8b, Sheer Y'CbCr[A] 10bv 4:2:2[:4], and Sheer Y'CbCr[A] 8bv 4:2:2[:4] also encode from and decode to Y'CbCr[A] 8bu 4:4:4[:4], but not losslessly and not always in real time.
The generic Sheer encoder and the Sheer Y'CbCr[A] 8bv 4:4:4[:4] encoder encode Y'CbCr[A] 8bu 4:4:4[:4] as Sheer Y'CbCr[A] 8bu 4:4:4[:4].
The specific Sheer codec corresponding to 8-bit Y'CbCr[A] 8bv 4:2:2[:4] is
- Sheer Y'CbCr[A] 8bv 4:2:2[:4]
which encodes from and decodes to Y'CbCr[A] 10bv 4:4:4[:4] losslessly in real time.
Sheer Y'CbCr[A] 10bv 4:2:2[:4] also encodes Y'CbCr[A] 8bv 4:2:2[:4] losslessly in real time.
Sheer RGB[A] 10b, Sheer RGB[A] 8b, Sheer Y'CbCr[A] 10bv 4:4:4[:4], and Sheer Y'CbCr[A] 8bv 4:4:4[:4] also encode from and decode to Y'CbCr[A] 8bv 4:2:2[:4],
though not losslessly and not always in real time.
The generic Sheer encoder encodes Y'CbCr[A] 8bv 4:2:2[:4] as Sheer Y'CbCr[A] 8bv 4:2:2[:4].
The specific Sheer codec corresponding to 8-bit Y'CbCr 8bw 4:2:2 is
which encodes from and decodes to Y'CbCr 8bw 4:2:2 losslessly in real time.
This is an obsolete format not supported by the other specific Sheer codecs.
The generic Sheer encoder encodes Y'CbCr 8bw 4:2:2 as Sheer Y'CbCr 8bw 4:2:2.
In the Sheer codec and Sheer format names, the 8b designation following the color-space name
indicates that the channel precision is 8 bits:
- Sheer RGB[A] 8b
- Sheer Y'CbCr[A] 8bu 4:4:4[:4]
- Sheer Y'CbCr[A] 8bv 4:4:4[:4]
- Sheer Y'CbCr[A] 8bv 4:2:2[:4]
- Sheer Y'CbCr 8bw 4:2:2
With 8-bit channels, each component theoretically has 28 = 256 possible distinct values,
which is close to the number of just noticeable differences that the human visual system can distinguish
under typical viewing conditions.
Just about all video digiters and digital video displays nowadays are standardized to 8-bit channels,
although high-end systems use 10 to 16 bits per channel, particularly for post-production work.
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Does SheerVideo support 10-bit channels? Yes, SheerVideo supports real-time lossless encoding and decoding of 10-bit data:
RGB[A] 10b, Y'CbCr[A] 10bv 4:4:4[:4], and Y'CbCr[A] 10bv 4:2:2[:4],
both progressive and interlaced, at all resolutions and frame rates, on both Mac and Windows.
SheerVideo supports the 10-bit RGB[A] 10b pixel formats
'b64a', 'L64A', and 'b48r';
the 10-bit Y'CbCr[A] 10bv 4:4:4[:4] pixel formats
'V416' and 'v410';
and the 10-bit Y'CbCr[A] 10bv 4:2:2[:4] pixel formats
'v210', 'v216', and 'Y216'.
The specific Sheer codec corresponding to 10-bit RGB[A] 10b is
which encodes from and decodes to RGB[A] 10b losslessly in real time.
Sheer RGB[A] 8b also encodes from and decodes to RGB[A] 10b in real time, but only to 8 bits of precision.
Sheer Y'CbCr[A] 10bv 4:4:4[:4], Sheer Y'CbCr[A] 8bv 4:4:4[:4], Sheer Y'CbCr[A] 10bv 4:2:2[:4], and Sheer Y'CbCr[A] 8bv 4:2:2[:4] codecs
also encode from and decode to RGB[A] 10b, but not losslessly, and not always in real time.
The generic Sheer codec uses Sheer RGB[A] 10b to encode RGB[A] 10b.
The specific Sheer codec corresponding to 10-bit Y'CbCr[A] 10bv 4:4:4[:4] is
- Sheer Y'CbCr[A] 10bv 4:4:4[:4]
which encodes from and decodes to Y'CbCr[A] 10bv 4:4:4[:4] losslessly in real time.
Sheer Y'CbCr[A] 8bv 4:4:4[:4] also encodes from and decodes to Y'CbCr[A] 10bv 4:4:4[:4] in real time, but only to 8 bits of precision.
Sheer RGB[A] 10b, Sheer RGB[A] 8b, Sheer Y'CbCr[A] 10bv 4:2:2[:4], and Sheer Y'CbCr[A] 8bv 4:2:2[:4] codecs
also encode from and decode to Y'CbCr[A] 10bv 4:4:4[:4], but not losslessly, and not always in real time.
The generic Sheer codec uses Sheer Y'CbCr[A] 10bv 4:4:4[:4] to encode Y'CbCr[A] 10bv 4:4:4[:4].
The specific Sheer codec corresponding to 10-bit Y'CbCr[A] 10bv 4:2:2[:4] is
- Sheer Y'CbCr[A] 10bv 4:2:2[:4]
which encodes from and decodes to Y'CbCr[A] 10bv 4:4:4[:4] losslessly in real time.
Sheer Y'CbCr[A] 8bv 4:2:2[:4] also encodes from and decodes to Y'CbCr[A] 10bv 4:2:2[:4] in real time, but only to 8 bits of precision.
Sheer RGB[A] 10b, Sheer RGB[A] 8b, Sheer Y'CbCr[A] 10bv 4:4:4[:4], and Sheer Y'CbCr[A] 8bv 4:4:4[:4] also encode from and decode to Y'CbCr[A] 10bv 4:2:2[:4],
though not losslessly and not always in real time.
The generic Sheer encoder encodes Y'CbCr[A] 10bv 4:2:2[:4] as Sheer Y'CbCr[A] 10bv 4:2:2[:4].
In the Sheer codec and Sheer format names, the 10b designation following the color-space name
indicates that the channel precision is 10 bits:
- Sheer RGB[A] 10b
- Sheer Y'CbCr[A] 10bv 4:4:4[:4]
- Sheer Y'CbCr[A] 10bv 4:2:2[:4]
With 10-bit channels, each component theoretically has 210 = 1024 possible distinct values,
which is greater than the number of just noticeable differences that the human visual system can distinguish
under optimal viewing conditions.
10-bit precision has long been the norm in high-end digitized film work, as in Cineon and DPX files;
as well as in high-end video work, as in the D5 format.
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Does SheerVideo support 16-bit channels? No, SheerVideo does not yet support real-time lossless encoding or decoding of any 16-bit formats. However, BitJazz already has 16-bit codecs in development,
and is planning to release them as soon as there is sufficient demand.
Note that the 10-bit Sheer codecs make use of the additional precision in 16-bit pixel formats for lossless color conversion with Synchromy.
For example, when decoding Sheer Y'CbCr[A] 10bv 4:4:4[:4] to 16-bit pixel formats 'b64a', 'L64A', or 'b48r' and encoding it back to Sheer Y'CbCr[A] 10bv 4:4:4[:4],
the Sheer Y'CbCr[A] 10bv 4:4:4[:4] codec utilizes 12 bits of precision for lossless conversion.
With 16-bit channels, each component theoretically has 216 = 65536 possible distinct values,
which is far beyond the number of just noticeable differences that the human visual system can distinguish under optimal viewing conditions,
but is more convenient when capturing under widely varying lighting conditions,
and for intermediate results during editing.
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