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1.5x-2x faster encoding for method 3 and up

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using token-buffer (that is: slightly more memory. O(output_size))

This change is ON by default. To return to previous behaviour, use
'cwebp -low_memory' or set config.low_memory to true.

Side-effect of this new mode: it forces 1 partition only (which was
default anyway), and makes some statistics about the bitstream
no longer available. cwebp will no longer report 'intra4-coeffs', etc.

This mode also doesn't work (yet) with multi-pass, and -low_memory
is currently forced for multi-pass.

also: reversed the flag: USE_TOKEN_BUFFER -> DISABLE_TOKEN_BUFFER
also: fixed the kAverageBytesPerMB estimate

Change-Id: I4ea80382038d6df4309663e0cb7bd88d9bca9cf1
This commit is contained in:
skal
2013-03-12 00:37:42 +01:00
committed by James Zern
parent be2fd1735a
commit 9bfbdd144f
10 changed files with 346 additions and 184 deletions
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32
src/enc/vp8enci.h
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@ -175,6 +175,9 @@ struct VP8Histogram {
int distribution[MAX_COEFF_THRESH + 1];
};
// Uncomment the following to remove token-buffer code:
// #define DISABLE_TOKEN_BUFFER
//------------------------------------------------------------------------------
// Headers
@ -327,12 +330,10 @@ void VP8SetSegment(const VP8EncIterator* const it, int segment);
//------------------------------------------------------------------------------
// Paginated token buffer
// WIP:#define USE_TOKEN_BUFFER
typedef struct VP8Tokens VP8Tokens; // struct details in token.c
typedef struct {
#ifdef USE_TOKEN_BUFFER
#if !defined(DISABLE_TOKEN_BUFFER)
VP8Tokens* pages_; // first page
VP8Tokens** last_page_; // last page
uint16_t* tokens_; // set to (*last_page_)->tokens_
@ -344,15 +345,22 @@ typedef struct {
void VP8TBufferInit(VP8TBuffer* const b); // initialize an empty buffer
void VP8TBufferClear(VP8TBuffer* const b); // de-allocate pages memory
#ifdef USE_TOKEN_BUFFER
#if !defined(DISABLE_TOKEN_BUFFER)
int VP8EmitTokens(const VP8TBuffer* const b, VP8BitWriter* const bw,
// Finalizes bitstream when probabilities are known.
// Deletes the allocated token memory if final_pass is true.
int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw,
const uint8_t* const probas, int final_pass);
int VP8RecordCoeffTokens(int ctx, int first, int last,
const int16_t* const coeffs, VP8TBuffer* tokens);
// record the coding of coefficients without knowing the probabilities yet
int VP8RecordCoeffTokens(int ctx, int coeff_type, int first, int last,
const int16_t* const coeffs,
VP8TBuffer* const tokens);
// unused for now
void VP8TokenToStats(const VP8TBuffer* const b, proba_t* const stats);
#endif // USE_TOKEN_BUFFER
#endif // !DISABLE_TOKEN_BUFFER
//------------------------------------------------------------------------------
// VP8Encoder
@ -377,12 +385,10 @@ struct VP8Encoder {
// per-partition boolean decoders.
VP8BitWriter bw_; // part0
VP8BitWriter parts_[MAX_NUM_PARTITIONS]; // token partitions
VP8TBuffer tokens_; // token buffer
int percent_; // for progress
int use_tokens_; // if true, use Token buffer
VP8TBuffer tokens_; // token buffer
// transparency blob
int has_alpha_;
uint8_t* alpha_data_; // non-NULL if transparency is present
@ -419,6 +425,8 @@ struct VP8Encoder {
VP8RDLevel rd_opt_level_; // Deduced from method_.
int max_i4_header_bits_; // partition #0 safeness factor
int thread_level_; // derived from config->thread_level
int do_search_; // derived from config->target_XXX
int use_tokens_; // if true, use token buffer
// Memory
VP8MBInfo* mb_info_; // contextual macroblock infos (mb_w_ + 1)
@ -480,7 +488,7 @@ int VP8GetCostLuma4(VP8EncIterator* const it, const int16_t levels[16]);
int VP8GetCostUV(VP8EncIterator* const it, const VP8ModeScore* const rd);
// Main coding calls
int VP8EncLoop(VP8Encoder* const enc);
int VP8StatLoop(VP8Encoder* const enc);
int VP8EncTokenLoop(VP8Encoder* const enc);
// in webpenc.c
// Assign an error code to a picture. Return false for convenience.