third_party/libwebp/enc/vp8li.h

   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_H_
  15 #define WEBP_ENC_VP8LI_H_
  16
  17 #include "./backward_references.h"
  18 #include "./histogram.h"
  19 #include "../utils/bit_writer.h"
  20 #include "../webp/encode.h"
  21 #include "../webp/format_constants.h"
  22
  23 #ifdef __cplusplus
  24 extern "C" {
  25 #endif
  26
  27 typedef struct {
  28   const WebPConfig* config_;    // user configuration and parameters
  29   const WebPPicture* pic_;      // input picture.
  30
  31   uint32_t* argb_;              // Transformed argb image data.
  32   uint32_t* argb_scratch_;      // Scratch memory for argb rows
  33                                 // (used for prediction).
  34   uint32_t* transform_data_;    // Scratch memory for transform data.
  35   int       current_width_;     // Corresponds to packed image width.
  36
  37   // Encoding parameters derived from quality parameter.
  38   int histo_bits_;
  39   int transform_bits_;
  40   int cache_bits_;        // If equal to 0, don't use color cache.
  41
  42   // Encoding parameters derived from image characteristics.
  43   int use_cross_color_;
  44   int use_subtract_green_;
  45   int use_predict_;
  46   int use_palette_;
  47   int palette_size_;
  48   uint32_t palette_[MAX_PALETTE_SIZE];
  49
  50   // Some 'scratch' (potentially large) objects.
  51   struct VP8LBackwardRefs refs_[2];  // Backward Refs array corresponding to
  52                                      // LZ77 & RLE coding.
  53   VP8LHashChain hash_chain_;         // HashChain data for constructing
  54                                      // backward references.
  55 } VP8LEncoder;
  56
  57 //------------------------------------------------------------------------------
  58 // internal functions. Not public.
  59
  60 // Encodes the picture.
  61 // Returns 0 if config or picture is NULL or picture doesn't have valid argb
  62 // input.
  63 int VP8LEncodeImage(const WebPConfig* const config,
  64                     const WebPPicture* const picture);
  65
  66 // Encodes the main image stream using the supplied bit writer.
  67 WebPEncodingError VP8LEncodeStream(const WebPConfig* const config,
  68                                    const WebPPicture* const picture,
  69                                    VP8LBitWriter* const bw);
  70
  71 //------------------------------------------------------------------------------
  72
  73 #ifdef __cplusplus
  74 }    // extern "C"
  75 #endif
  76
  77 #endif  /* WEBP_ENC_VP8LI_H_ */