src/net/instaweb/rewriter/public/webp_optimizer.h

/*
 * Copyright 2011 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// Author: jmaessen@google.com (Jan Maessen)

#ifndef NET_INSTAWEB_REWRITER_PUBLIC_WEBP_OPTIMIZER_H_
#define NET_INSTAWEB_REWRITER_PUBLIC_WEBP_OPTIMIZER_H_

#include "pagespeed/kernel/base/string.h"

namespace net_instaweb {

class MessageHandler;

// Progress hook for WebP conversions.
typedef bool (*WebpProgressHook)(int percent, void* user_data);

// Quality taken when no quality is passed through flags or when no quality is
// retrieved from JpegUtils::GetImageQualityFromImage.
const int kNoQualityGiven = -1;

// Optimizer in the style of pagespeed/kernel/image/jpeg_optimizer.h that
// creates a webp-formatted image in compressed_webp from the jpeg image in
// original_jpeg.  Indicates failure by returning false, in which case
// compressed_webp may be filled with junk.
bool OptimizeWebp(const GoogleString& original_jpeg, int configured_quality,
                  WebpProgressHook progress_hook, void* progress_hook_data,
                  GoogleString* compressed_webp,
                  MessageHandler* message_handler);

// Reduce the quality of the webp image. Indicates failure by returning false.
// WebP quality varies from 1 to 100. Original image will be returned if input
// quality is <1.
bool ReduceWebpImageQuality(const GoogleString& original_webp,
                            int quality, GoogleString* compressed_webp);

}  // namespace net_instaweb

#endif  // NET_INSTAWEB_REWRITER_PUBLIC_WEBP_OPTIMIZER_H_