| // Copyright 2011 Google Inc. All Rights Reserved. |
| // |
| // Use of this source code is governed by a BSD-style license |
| // that can be found in the COPYING file in the root of the source |
| // tree. An additional intellectual property rights grant can be found |
| // in the file PATENTS. All contributing project authors may |
| // be found in the AUTHORS file in the root of the source tree. |
| // ----------------------------------------------------------------------------- |
| // |
| // Spatial prediction using various filters |
| // |
| // Author: Urvang (urvang@google.com) |
| |
| #ifndef WEBP_UTILS_FILTERS_H_ |
| #define WEBP_UTILS_FILTERS_H_ |
| |
| #include "../webp/types.h" |
| |
| #if defined(__cplusplus) || defined(c_plusplus) |
| extern "C" { |
| #endif |
| |
| // Filters. |
| typedef enum { |
| WEBP_FILTER_NONE = 0, |
| WEBP_FILTER_HORIZONTAL, |
| WEBP_FILTER_VERTICAL, |
| WEBP_FILTER_GRADIENT, |
| WEBP_FILTER_LAST = WEBP_FILTER_GRADIENT + 1, // end marker |
| WEBP_FILTER_BEST, |
| WEBP_FILTER_FAST |
| } WEBP_FILTER_TYPE; |
| |
| typedef void (*WebPFilterFunc)(const uint8_t* in, int width, int height, |
| int stride, uint8_t* out); |
| typedef void (*WebPUnfilterFunc)(int width, int height, int stride, |
| uint8_t* data); |
| |
| // Filter the given data using the given predictor. |
| // 'in' corresponds to a 2-dimensional pixel array of size (stride * height) |
| // in raster order. |
| // 'stride' is number of bytes per scan line (with possible padding). |
| // 'out' should be pre-allocated. |
| extern const WebPFilterFunc WebPFilters[WEBP_FILTER_LAST]; |
| |
| // In-place reconstruct the original data from the given filtered data. |
| extern const WebPUnfilterFunc WebPUnfilters[WEBP_FILTER_LAST]; |
| |
| // Fast estimate of a potentially good filter. |
| extern WEBP_FILTER_TYPE EstimateBestFilter(const uint8_t* data, |
| int width, int height, int stride); |
| |
| #if defined(__cplusplus) || defined(c_plusplus) |
| } // extern "C" |
| #endif |
| |
| #endif /* WEBP_UTILS_FILTERS_H_ */ |