tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

vp8li_enc.h (5066B)


      1 // Copyright 2012 Google Inc. All Rights Reserved.
      2 //
      3 // Use of this source code is governed by a BSD-style license
      4 // that can be found in the COPYING file in the root of the source
      5 // tree. An additional intellectual property rights grant can be found
      6 // in the file PATENTS. All contributing project authors may
      7 // be found in the AUTHORS file in the root of the source tree.
      8 // -----------------------------------------------------------------------------
      9 //
     10 // Lossless encoder: internal header.
     11 //
     12 // Author: Vikas Arora (vikaas.arora@gmail.com)
     13 
     14 #ifndef WEBP_ENC_VP8LI_ENC_H_
     15 #define WEBP_ENC_VP8LI_ENC_H_
     16 
     17 #ifdef HAVE_CONFIG_H
     18 #include "src/webp/config.h"
     19 #endif
     20 
     21 #include <stddef.h>
     22 
     23 // Either WEBP_NEAR_LOSSLESS is defined as 0 in config.h when compiling to
     24 // disable near-lossless, or it is enabled by default.
     25 #ifndef WEBP_NEAR_LOSSLESS
     26 #define WEBP_NEAR_LOSSLESS 1
     27 #endif
     28 
     29 #include "src/webp/types.h"
     30 #include "src/enc/backward_references_enc.h"
     31 #include "src/enc/histogram_enc.h"
     32 #include "src/utils/bit_writer_utils.h"
     33 #include "src/webp/encode.h"
     34 #include "src/webp/format_constants.h"
     35 
     36 #ifdef __cplusplus
     37 extern "C" {
     38 #endif
     39 
     40 // maximum value of 'transform_bits' in VP8LEncoder.
     41 #define MAX_TRANSFORM_BITS (MIN_TRANSFORM_BITS + (1 << NUM_TRANSFORM_BITS) - 1)
     42 
     43 typedef enum {
     44  kEncoderNone = 0,
     45  kEncoderARGB,
     46  kEncoderNearLossless,
     47  kEncoderPalette
     48 } VP8LEncoderARGBContent;
     49 
     50 typedef struct {
     51  const WebPConfig* config;      // user configuration and parameters
     52  const WebPPicture* pic;        // input picture.
     53 
     54  uint32_t* argb;                       // Transformed argb image data.
     55  VP8LEncoderARGBContent argb_content;  // Content type of the argb buffer.
     56  uint32_t* argb_scratch;               // Scratch memory for argb rows
     57                                        // (used for prediction).
     58  uint32_t* transform_data;             // Scratch memory for transform data.
     59  uint32_t* transform_mem;              // Currently allocated memory.
     60  size_t    transform_mem_size;         // Currently allocated memory size.
     61 
     62  int       current_width;       // Corresponds to packed image width.
     63 
     64  // Encoding parameters derived from quality parameter.
     65  int histo_bits;
     66  int predictor_transform_bits;    // <= MAX_TRANSFORM_BITS
     67  int cross_color_transform_bits;  // <= MAX_TRANSFORM_BITS
     68  int cache_bits;        // If equal to 0, don't use color cache.
     69 
     70  // Encoding parameters derived from image characteristics.
     71  int use_cross_color;
     72  int use_subtract_green;
     73  int use_predict;
     74  int use_palette;
     75  int palette_size;
     76  uint32_t palette[MAX_PALETTE_SIZE];
     77  // Sorted version of palette for cache purposes.
     78  uint32_t palette_sorted[MAX_PALETTE_SIZE];
     79 
     80  // Some 'scratch' (potentially large) objects.
     81  struct VP8LBackwardRefs refs[4];  // Backward Refs array for temporaries.
     82  VP8LHashChain hash_chain;         // HashChain data for constructing
     83                                    // backward references.
     84 } VP8LEncoder;
     85 
     86 //------------------------------------------------------------------------------
     87 // internal functions. Not public.
     88 
     89 // Encodes the picture.
     90 // Returns 0 if config or picture is NULL or picture doesn't have valid argb
     91 // input.
     92 int VP8LEncodeImage(const WebPConfig* const config,
     93                    const WebPPicture* const picture);
     94 
     95 // Encodes the main image stream using the supplied bit writer.
     96 // Returns false in case of error (stored in picture->error_code).
     97 int VP8LEncodeStream(const WebPConfig* const config,
     98                     const WebPPicture* const picture, VP8LBitWriter* const bw);
     99 
    100 #if (WEBP_NEAR_LOSSLESS == 1)
    101 // in near_lossless.c
    102 // Near lossless preprocessing in RGB color-space.
    103 int VP8ApplyNearLossless(const WebPPicture* const picture, int quality,
    104                         uint32_t* const argb_dst);
    105 #endif
    106 
    107 //------------------------------------------------------------------------------
    108 // Image transforms in predictor.c.
    109 
    110 // pic and percent are for progress.
    111 // Returns false in case of error (stored in pic->error_code).
    112 int VP8LResidualImage(int width, int height, int min_bits, int max_bits,
    113                      int low_effort, uint32_t* const argb,
    114                      uint32_t* const argb_scratch, uint32_t* const image,
    115                      int near_lossless, int exact, int used_subtract_green,
    116                      const WebPPicture* const pic, int percent_range,
    117                      int* const percent, int* const best_bits);
    118 
    119 int VP8LColorSpaceTransform(int width, int height, int bits, int quality,
    120                            uint32_t* const argb, uint32_t* image,
    121                            const WebPPicture* const pic, int percent_range,
    122                            int* const percent, int* const best_bits);
    123 
    124 void VP8LOptimizeSampling(uint32_t* const image, int full_width,
    125                          int full_height, int bits, int max_bits,
    126                          int* best_bits_out);
    127 
    128 //------------------------------------------------------------------------------
    129 
    130 #ifdef __cplusplus
    131 }    // extern "C"
    132 #endif
    133 
    134 #endif  // WEBP_ENC_VP8LI_ENC_H_