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move the decoder sourcetree to a sub-location src/dec

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to make room for future libs sources

also extract the types declaration into its own types.h file

Change-Id: I8bae8a323a479a29375cf509792228ae6af51c7a
This commit is contained in:
Pascal Massimino
2011-01-06 07:25:43 -08:00
parent a9b3eab6fd
commit 6421a7a4fb
22 changed files with 17747 additions and 23160 deletions
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78
src/dec/bits.c Normal file
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// Copyright 2010 Google Inc.
//
// This code is licensed under the same terms as WebM:
// Software License Agreement: http://www.webmproject.org/license/software/
// Additional IP Rights Grant: http://www.webmproject.org/license/additional/
// -----------------------------------------------------------------------------
//
// Boolean decoder
//
// Author: Skal (pascal.massimino@gmail.com)
#include "bits.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
//-----------------------------------------------------------------------------
// VP8BitReader
void VP8Init(VP8BitReader* const br, const uint8_t* buf, uint32_t size) {
assert(br);
assert(buf);
br->range_ = 255 - 1;
br->eof_ = 0;
br->buf_ = buf;
br->buf_end_ = buf + size;
// Need two initial bytes.
br->value_ = (VP8GetByte(br) << 8) | VP8GetByte(br);
br->left_ = -8;
}
const uint8_t kVP8Log2Range[128] = {
7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
0
};
// range = ((range + 1) << kVP8Log2Range[range]) - 1
const uint8_t kVP8NewRange[128] = {
127, 127, 191, 127, 159, 191, 223, 127, 143, 159, 175, 191, 207, 223, 239,
127, 135, 143, 151, 159, 167, 175, 183, 191, 199, 207, 215, 223, 231, 239,
247, 127, 131, 135, 139, 143, 147, 151, 155, 159, 163, 167, 171, 175, 179,
183, 187, 191, 195, 199, 203, 207, 211, 215, 219, 223, 227, 231, 235, 239,
243, 247, 251, 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149,
151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179,
181, 183, 185, 187, 189, 191, 193, 195, 197, 199, 201, 203, 205, 207, 209,
211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239,
241, 243, 245, 247, 249, 251, 253, 127
};
//-----------------------------------------------------------------------------
// Higher-level calls
uint32_t VP8GetValue(VP8BitReader* const br, int bits) {
uint32_t v = 0;
while (bits-- > 0) {
v |= VP8GetBit(br, 0x80) << bits;
}
return v;
}
int32_t VP8GetSignedValue(VP8BitReader* const br, int bits) {
const int value = VP8GetValue(br, bits);
return VP8Get(br) ? -value : value;
}
//-----------------------------------------------------------------------------
#if defined(__cplusplus) || defined(c_plusplus)
} // extern "C"
#endif