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Use a consistent capitalization for 'Snow' as discussed on the list

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Originally committed as revision 11880 to svn://svn.ffmpeg.org/ffmpeg/trunk
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Mike Melanson 2008-02-08 19:17:46 +00:00
parent 91208916c6
commit ead6ebdd44
1 changed files with 8 additions and 8 deletions
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doc/snow.txt
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@ -1,18 +1,18 @@
============================================= =============================================
SNOW Video Codec Specification Draft 20080110 Snow Video Codec Specification Draft 20080110
============================================= =============================================
Introduction: Introduction:
============= =============
This specification describes the SNOW bitstream syntax and semantics as This specification describes the Snow bitstream syntax and semantics as
well as the formal SNOW decoding process. well as the formal Snow decoding process.
The decoding process is described precisely and any compliant decoder The decoding process is described precisely and any compliant decoder
MUST produce the exact same output for a spec-conformant SNOW stream. MUST produce the exact same output for a spec-conformant Snow stream.
For encoding, though, any process which generates a stream compliant to For encoding, though, any process which generates a stream compliant to
the syntactical and semantic requirements and which is decodable by the syntactical and semantic requirements and which is decodable by
the process described in this spec shall be considered a conformant the process described in this spec shall be considered a conformant
SNOW encoder. Snow encoder.
Definitions: Definitions:
============ ============
@ -315,7 +315,7 @@ Binary Range Coder:
The implemented range coder is an adapted version based upon "Range encoding: The implemented range coder is an adapted version based upon "Range encoding:
an algorithm for removing redundancy from a digitised message." by G. N. N. an algorithm for removing redundancy from a digitised message." by G. N. N.
Martin. Martin.
The symbols encoded by the snow range coder are bits (0|1). The The symbols encoded by the Snow range coder are bits (0|1). The
associated probabilities are not fix but change depending on the symbol mix associated probabilities are not fix but change depending on the symbol mix
seen so far. seen so far.
@ -486,7 +486,7 @@ the remaining points shall be bilinearly interpolated from the
up to 4 surrounding halfpel and fullpel points, again rounding should be to up to 4 surrounding halfpel and fullpel points, again rounding should be to
nearest and halfway values rounded up nearest and halfway values rounded up
compliant snow decoders MUST support 1-1/8 pel luma and 1/2-1/16 pel chroma compliant Snow decoders MUST support 1-1/8 pel luma and 1/2-1/16 pel chroma
interpolation at least interpolation at least
@ -562,7 +562,7 @@ s[w ] shall be considered equivalent to s[w-2]
| + | + | + | + +1/2 | + | + | + | + +1/2
snows 9/7 Integer filter: Snow's 9/7 Integer filter:
1. s[i] -= (3*(s[i-1] + s[i+1]) + 4)>>3; for all even i < w 1. s[i] -= (3*(s[i-1] + s[i+1]) + 4)>>3; for all even i < w
2. s[i] -= s[i-1] + s[i+1] ; for all odd i < w 2. s[i] -= s[i-1] + s[i+1] ; for all odd i < w
3. s[i] += ( s[i-1] + s[i+1] + 4*s[i] + 8)>>4; for all even i < w 3. s[i] += ( s[i-1] + s[i+1] + 4*s[i] + 8)>>4; for all even i < w