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