libwebp/examples/gif2webp_util.h
Urvang Joshi 38efdc2e9c Simplify the gif2webp tool: move the optimization details to util
Specifically:
- Merge OptimizeAndEncodeFrame with WebPFrameCacheAddFrame: they use the same
  if-else structure.
- Move maintenance of 'prev_canvas' and 'curr_canvas' to util.
- Move ReduceTransparency() and FlattenPixels() calls to SetFrame(): This is in
  preparation for the next patch: which will try try lossless encoding for
  each frame, even when '-lossy' option is given.
- Make most methods static inside util.

No changes to output expected.

Change-Id: I1f65af25246665508cb20f0f6e338f9aaba9367b
2013-10-14 14:39:46 -07:00

79 lines
2.9 KiB
C

// Copyright 2013 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.
// -----------------------------------------------------------------------------
//
// Helper structs and methods for gif2webp tool.
//
// Author: Urvang (urvang@google.com)
#ifndef WEBP_EXAMPLES_GIF2WEBP_UTIL_H_
#define WEBP_EXAMPLES_GIF2WEBP_UTIL_H_
#include <stdlib.h>
#include "webp/mux.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
//------------------------------------------------------------------------------
// Helper utilities.
#define WEBP_UTIL_TRANSPARENT_COLOR 0x00ffffff
struct WebPPicture;
typedef struct {
int x_offset, y_offset, width, height;
} WebPFrameRect;
// Clear pixels in 'picture' within given 'rect' to transparent color.
void WebPUtilClearPic(struct WebPPicture* const picture,
const WebPFrameRect* const rect);
//------------------------------------------------------------------------------
// Frame cache.
typedef struct WebPFrameCache WebPFrameCache;
// Given the minimum distance between key frames 'kmin' and maximum distance
// between key frames 'kmax', returns an appropriately allocated cache object.
// Use WebPFrameCacheDelete() to deallocate the 'cache'.
WebPFrameCache* WebPFrameCacheNew(int width, int height,
size_t kmin, size_t kmax);
// Release all the frame data from 'cache' and free 'cache'.
void WebPFrameCacheDelete(WebPFrameCache* const cache);
// Given an image described by 'frame', 'info' and 'orig_rect', optimize it for
// WebP, encode it and add it to 'cache'.
// This takes care of frame disposal too, according to 'info->dispose_method'.
int WebPFrameCacheAddFrame(WebPFrameCache* const cache,
const WebPConfig* const config,
const WebPFrameRect* const orig_rect,
WebPPicture* const frame,
WebPMuxFrameInfo* const info);
// Flush the *ready* frames from cache and add them to 'mux'. If 'verbose' is
// true, prints the information about these frames.
WebPMuxError WebPFrameCacheFlush(WebPFrameCache* const cache, int verbose,
WebPMux* const mux);
// Similar to 'WebPFrameCacheFlushFrames()', but flushes *all* the frames.
WebPMuxError WebPFrameCacheFlushAll(WebPFrameCache* const cache, int verbose,
WebPMux* const mux);
//------------------------------------------------------------------------------
#if defined(__cplusplus) || defined(c_plusplus)
} // extern "C"
#endif
#endif // WEBP_EXAMPLES_GIF2WEBP_UTIL_H_