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small cosmetics on TokenBuffer.

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Change-Id: I7c33651ed8e3a151aef44247db5fb1e8bf41f8ba
This commit is contained in:
Pascal Massimino 2015-03-03 00:48:28 +01:00
parent 76394c09d4
commit c9b8ea0eef
1 changed files with 29 additions and 29 deletions
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58
src/enc/token.c
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@ -30,15 +30,15 @@
#define MIN_PAGE_SIZE 8192 // minimum number of token per page
#define FIXED_PROBA_BIT (1u << 14)
typedef uint16_t token_t; // bit#15: bit
// bit #14: constant proba or idx
// bits 0..13: slot or constant proba
typedef uint16_t token_t; // bit #15: bit value
// bit #14: flags for constant proba or idx
// bits #0..13: slot or constant proba
struct VP8Tokens {
VP8Tokens* next_; // pointer to next page
};
// Token data is located in memory just after the next_ field.
// This macro is used to return their address and hide the trick.
#define TOKEN_DATA(p) ((token_t*)&(p)[1])
#define TOKEN_DATA(p) ((const token_t*)&(p)[1])
//------------------------------------------------------------------------------
@ -65,8 +65,8 @@ void VP8TBufferClear(VP8TBuffer* const b) {
static int TBufferNewPage(VP8TBuffer* const b) {
VP8Tokens* page = NULL;
const size_t size = sizeof(*page) + b->page_size_ * sizeof(token_t);
if (!b->error_) {
const size_t size = sizeof(*page) + b->page_size_ * sizeof(token_t);
page = (VP8Tokens*)WebPSafeMalloc(1ULL, size);
}
if (page == NULL) {
@ -78,19 +78,19 @@ static int TBufferNewPage(VP8TBuffer* const b) {
*b->last_page_ = page;
b->last_page_ = &page->next_;
b->left_ = b->page_size_;
b->tokens_ = TOKEN_DATA(page);
b->tokens_ = (token_t*)TOKEN_DATA(page);
return 1;
}
//------------------------------------------------------------------------------
#define TOKEN_ID(t, b, ctx, p) \
((p) + NUM_PROBAS * ((ctx) + NUM_CTX * ((b) + NUM_BANDS * (t))))
#define TOKEN_ID(t, b, ctx) \
(NUM_PROBAS * ((ctx) + NUM_CTX * ((b) + NUM_BANDS * (t))))
static WEBP_INLINE int AddToken(VP8TBuffer* const b,
int bit, uint32_t proba_idx) {
static WEBP_INLINE uint32_t AddToken(VP8TBuffer* const b,
uint32_t bit, uint32_t proba_idx) {
assert(proba_idx < FIXED_PROBA_BIT);
assert(bit == 0 || bit == 1);
assert(bit <= 1);
if (b->left_ > 0 || TBufferNewPage(b)) {
const int slot = --b->left_;
b->tokens_[slot] = (bit << 15) | proba_idx;
@ -99,20 +99,21 @@ static WEBP_INLINE int AddToken(VP8TBuffer* const b,
}
static WEBP_INLINE void AddConstantToken(VP8TBuffer* const b,
int bit, int proba) {
uint32_t bit, uint32_t proba) {
assert(proba < 256);
assert(bit == 0 || bit == 1);
assert(bit <= 1);
if (b->left_ > 0 || TBufferNewPage(b)) {
const int slot = --b->left_;
b->tokens_[slot] = (bit << 15) | FIXED_PROBA_BIT | proba;
}
}
int VP8RecordCoeffTokens(int ctx, int coeff_type, int first, int last,
int VP8RecordCoeffTokens(const int ctx, const int coeff_type,
int first, int last,
const int16_t* const coeffs,
VP8TBuffer* const tokens) {
int n = first;
uint32_t base_id = TOKEN_ID(coeff_type, n, ctx, 0);
uint32_t base_id = TOKEN_ID(coeff_type, n, ctx);
if (!AddToken(tokens, last >= 0, base_id + 0)) {
return 0;
}
@ -120,14 +121,13 @@ int VP8RecordCoeffTokens(int ctx, int coeff_type, int first, int last,
while (n < 16) {
const int c = coeffs[n++];
const int sign = c < 0;
int v = sign ? -c : c;
const uint32_t v = sign ? -c : c;
if (!AddToken(tokens, v != 0, base_id + 1)) {
ctx = 0;
base_id = TOKEN_ID(coeff_type, VP8EncBands[n], ctx, 0);
base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 0); // ctx=0
continue;
}
if (!AddToken(tokens, v > 1, base_id + 2)) {
ctx = 1;
base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 1); // ctx=1
} else {
if (!AddToken(tokens, v > 4, base_id + 3)) {
if (AddToken(tokens, v != 2, base_id + 4))
@ -142,40 +142,40 @@ int VP8RecordCoeffTokens(int ctx, int coeff_type, int first, int last,
} else {
int mask;
const uint8_t* tab;
if (v < 3 + (8 << 1)) { // VP8Cat3 (3b)
uint32_t residue = v - 3;
if (residue < (8 << 1)) { // VP8Cat3 (3b)
AddToken(tokens, 0, base_id + 8);
AddToken(tokens, 0, base_id + 9);
v -= 3 + (8 << 0);
residue -= (8 << 0);
mask = 1 << 2;
tab = VP8Cat3;
} else if (v < 3 + (8 << 2)) { // VP8Cat4 (4b)
} else if (residue < (8 << 2)) { // VP8Cat4 (4b)
AddToken(tokens, 0, base_id + 8);
AddToken(tokens, 1, base_id + 9);
v -= 3 + (8 << 1);
residue -= (8 << 1);
mask = 1 << 3;
tab = VP8Cat4;
} else if (v < 3 + (8 << 3)) { // VP8Cat5 (5b)
} else if (residue < (8 << 3)) { // VP8Cat5 (5b)
AddToken(tokens, 1, base_id + 8);
AddToken(tokens, 0, base_id + 10);
v -= 3 + (8 << 2);
residue -= (8 << 2);
mask = 1 << 4;
tab = VP8Cat5;
} else { // VP8Cat6 (11b)
AddToken(tokens, 1, base_id + 8);
AddToken(tokens, 1, base_id + 10);
v -= 3 + (8 << 3);
residue -= (8 << 3);
mask = 1 << 10;
tab = VP8Cat6;
}
while (mask) {
AddConstantToken(tokens, !!(v & mask), *tab++);
AddConstantToken(tokens, !!(residue & mask), *tab++);
mask >>= 1;
}
}
ctx = 2;
base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 2); // ctx=2
}
AddConstantToken(tokens, sign, 128);
base_id = TOKEN_ID(coeff_type, VP8EncBands[n], ctx, 0);
if (n == 16 || !AddToken(tokens, n <= last, base_id + 0)) {
return 1; // EOB
}