jpeg_data_decoder.h

/*
 * Copyright 2016 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.
 */

// Library to decode jpeg coefficients into an RGB image.

#ifndef KNUSPERLI_JPEG_DATA_DECODER_H_
#define KNUSPERLI_JPEG_DATA_DECODER_H_

#include <stdint.h>

#include "jpeg_data.h"

namespace knusperli {

// Decodes the parsed jpeg coefficients into an RGB image.
// There can be only either 1 or 3 image components, in either case, an RGB
// output image will be generated.
// Only YUV420 and YUV444 sampling factors are supported.
// Vector will be empty if a decoding error occurred.
std::vector<uint8_t> DecodeJpegToRGB(const JPEGData& jpg);

// Mimic libjpeg's heuristics to guess jpeg color space.
// Requires that the jpg has 3 components.
bool HasYCbCrColorSpace(const JPEGData& jpg);

}  // namespace knusperli

#endif  // KNUSPERLI_JPEG_DATA_DECODER_H_