| // Copyright 2015 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. |
| // |
| //////////////////////////////////////////////////////////////////////////////// |
| // |
| // The purpose of the preview-image-extractor (piex) is to find and extract the |
| // largest JPEG compressed preview image contained in a RAW file. |
| // |
| // Even for unsupported RAW files we want to provide high quality images using a |
| // dedicated, small and portable library. That is possible by taking the preview |
| // image contained in all RAW files. |
| // |
| // Typically a preview image is stored as JPEG compressed, full size (or at |
| // least half size) image in a RAW file. |
| // |
| // A typical client code snippet: |
| // |
| // // In C++ |
| // PreviewImageData image_data; |
| // unique_ptr<StreamInterface> data_stream(new DataStream(file)); |
| // Error err = GetPreviewImageData(data_stream.get(), &image_data)); |
| // if (err == Error::kFail) { |
| // // The input data seems to be broken. |
| // return; |
| // } else if (err == Error::kUnsupported) { |
| // // The input data is not supported. |
| // return; |
| // } |
| // |
| // // Uncompress the JPEG as usual, e.g. on Android with the BitmapFactory: |
| // // In Java |
| // Bitmap bitmap = BitmapFactory.decodeByteArray( |
| // file.at(image_data.preview_offset), image_data.preview_length); |
| |
| #ifndef PIEX_PIEX_H_ |
| #define PIEX_PIEX_H_ |
| |
| #include <string> |
| #include <vector> |
| |
| #include "src/piex_types.h" |
| |
| namespace piex { |
| |
| // Returns the maximum number of bytes IsRaw() will read from the stream. |
| size_t BytesRequiredForIsRaw(); |
| |
| // Returns true if 'data' contains a RAW file format, even if it is not |
| // supported by Piex, false otherwise. Reads at most BytesRequiredForIsRaw() |
| // from the stream. |
| bool IsRaw(StreamInterface* data); |
| |
| // Gets the largest JPEG compressed preview image data. On success |
| // 'preview_image_data' contains image metadata, the unverified length and the |
| // offset to a JPEG compressed image from the beginning of the file. |
| // |
| // Returns 'kFail' when something with the data is wrong. |
| // Returns 'kUnsupported' if file format is not supported. |
| // |
| // One could check the "preview_image_data->preview_length != 0" for the |
| // existance of a preview image. |
| Error GetPreviewImageData(StreamInterface* data, |
| PreviewImageData* preview_image_data); |
| |
| // Returns true if the full width and height and the mosaic pattern dimension of |
| // a DNG image could be obtained. False otherwise. |
| bool GetDngInformation(StreamInterface* data, std::uint32_t* width, |
| std::uint32_t* height, |
| std::vector<std::uint32_t>* cfa_pattern_dim); |
| |
| // Returns true if Exif orientation for the image can be obtained. False |
| // otherwise. |
| bool GetOrientation(StreamInterface* data, std::uint32_t* orientation); |
| |
| // Returns a vector of upper case file extensions, which are used as a first |
| // step to quickly guess a supported file format. |
| std::vector<std::string> SupportedExtensions(); |
| |
| } // namespace piex |
| |
| #endif // PIEX_PIEX_H_ |
