// Copyright 2015 Google Inc.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//
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////////////////////////////////////////////////////////////////////////////////
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//
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// The purpose of the preview-image-extractor (piex) is to find and extract the
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// largest JPEG compressed preview image contained in a RAW file.
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//
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// Even for unsupported RAW files we want to provide high quality images using a
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// dedicated, small and portable library. That is possible by taking the preview
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// image contained in all RAW files.
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//
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// Typically a preview image is stored as JPEG compressed, full size (or at
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// least half size) image in a RAW file.
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//
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// A typical client code snippet:
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//
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// // In C++
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// PreviewImageData image_data;
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// unique_ptr<StreamInterface> data_stream(new DataStream(file));
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// Error err = GetPreviewImageData(data_stream.get(), &image_data));
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// if (err == Error::kFail) {
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// // The input data seems to be broken.
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// return;
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// } else if (err == Error::kUnsupported) {
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// // The input data is not supported.
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// return;
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// }
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//
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// // Uncompress the JPEG as usual, e.g. on Android with the BitmapFactory:
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// // In Java
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// Bitmap bitmap = BitmapFactory.decodeByteArray(
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// file.at(image_data.preview_offset), image_data.preview_length);
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#ifndef PIEX_PIEX_H_
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#define PIEX_PIEX_H_
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#include <string>
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#include <vector>
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#include "src/piex_types.h"
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namespace piex {
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// Returns the maximum number of bytes IsRaw() will read from the stream.
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size_t BytesRequiredForIsRaw();
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// Returns true if 'data' contains a RAW file format, even if it is not
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// supported by Piex, false otherwise. Reads at most BytesRequiredForIsRaw()
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// from the stream.
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bool IsRaw(StreamInterface* data);
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// Gets the largest JPEG compressed preview image data. On success
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// 'preview_image_data' contains image metadata, the unverified length and the
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// offset to a JPEG compressed image from the beginning of the file.
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//
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// Returns 'kFail' when something with the data is wrong.
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// Returns 'kUnsupported' if file format is not supported.
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//
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// One could check the "preview_image_data->preview_length != 0" for the
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// existance of a preview image.
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Error GetPreviewImageData(StreamInterface* data,
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PreviewImageData* preview_image_data);
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// Returns true if the full width and height and the mosaic pattern dimension of
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// a DNG image could be obtained. False otherwise.
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bool GetDngInformation(StreamInterface* data, std::uint32_t* width,
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std::uint32_t* height,
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std::vector<std::uint32_t>* cfa_pattern_dim);
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// Returns true if Exif orientation for the image can be obtained. False
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// otherwise.
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bool GetOrientation(StreamInterface* data, std::uint32_t* orientation);
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// Returns a vector of upper case file extensions, which are used as a first
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// step to quickly guess a supported file format.
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std::vector<std::string> SupportedExtensions();
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} // namespace piex
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#endif // PIEX_PIEX_H_
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