| // This file is part of OpenCV project. | |
| // It is subject to the license terms in the LICENSE file found in the top-level directory | |
| // of this distribution and at http://opencv.org/license.html. | |
| // | |
| // Copyright (C) 2021 Intel Corporation | |
| namespace cv { | |
| namespace gapi { | |
| namespace wip { | |
| namespace onevpl { | |
| struct GAPI_EXPORTS DataProviderException : public std::exception { | |
| DataProviderException(const std::string& descr); | |
| DataProviderException(std::string&& descr); | |
| virtual ~DataProviderException() = default; | |
| virtual const char* what() const noexcept override; | |
| private: | |
| std::string reason; | |
| }; | |
| struct GAPI_EXPORTS DataProviderSystemErrorException final : public DataProviderException { | |
| DataProviderSystemErrorException(int error_code, const std::string& description = std::string()); | |
| ~DataProviderSystemErrorException() = default; | |
| }; | |
| struct GAPI_EXPORTS DataProviderUnsupportedException final : public DataProviderException { | |
| DataProviderUnsupportedException(const std::string& description); | |
| ~DataProviderUnsupportedException() = default; | |
| }; | |
| struct GAPI_EXPORTS DataProviderImplementationException : public DataProviderException { | |
| DataProviderImplementationException(const std::string& description); | |
| ~DataProviderImplementationException() = default; | |
| }; | |
| /** | |
| * @brief Public interface allows to customize extraction of video stream data | |
| * used by onevpl::GSource instead of reading stream from file (by default). | |
| * | |
| * Interface implementation constructor MUST provide consistency and creates fully operable object. | |
| * If error happened implementation MUST throw `DataProviderException` kind exceptions | |
| * | |
| * @note Interface implementation MUST manage stream and other constructed resources by itself to avoid any kind of leak. | |
| * For simple interface implementation example please see `StreamDataProvider` in `tests/streaming/gapi_streaming_tests.cpp` | |
| */ | |
| struct GAPI_EXPORTS IDataProvider { | |
| using Ptr = std::shared_ptr<IDataProvider>; | |
| using mfx_codec_id_type = uint32_t; | |
| /** | |
| * NB: here is supposed to be forward declaration of mfxBitstream | |
| * But according to current oneVPL implementation it is impossible to forward | |
| * declare untagged struct mfxBitstream. | |
| * | |
| * IDataProvider makes sense only for HAVE_VPL is ON and to keep IDataProvider | |
| * interface API/ABI compliant between core library and user application layer | |
| * let's introduce wrapper mfx_bitstream which inherits mfxBitstream in private | |
| * G-API code section and declare forward for wrapper mfx_bitstream here | |
| */ | |
| struct mfx_bitstream; | |
| virtual ~IDataProvider() = default; | |
| /** | |
| * The function is used by onevpl::GSource to extract codec id from data | |
| * | |
| */ | |
| virtual mfx_codec_id_type get_mfx_codec_id() const = 0; | |
| /** | |
| * The function is used by onevpl::GSource to extract binary data stream from @ref IDataProvider | |
| * implementation. | |
| * | |
| * It MUST throw `DataProviderException` kind exceptions in fail cases. | |
| * It MUST return MFX_ERR_MORE_DATA in EOF which considered as not-fail case. | |
| * | |
| * @param in_out_bitsream the input-output reference on MFX bitstream buffer which MUST be empty at the first request | |
| * to allow implementation to allocate it by itself and to return back. Subsequent invocation of `fetch_bitstream_data` | |
| * MUST use the previously used in_out_bitsream to avoid skipping rest of frames which haven't been consumed | |
| * @return true for fetched data, false on EOF and throws exception on error | |
| */ | |
| virtual bool fetch_bitstream_data(std::shared_ptr<mfx_bitstream> &in_out_bitsream) = 0; | |
| /** | |
| * The function is used by onevpl::GSource to check more binary data availability. | |
| * | |
| * It MUST return TRUE in case of EOF and NO_THROW exceptions. | |
| * | |
| * @return boolean value which detects end of stream | |
| */ | |
| virtual bool empty() const = 0; | |
| }; | |
| } // namespace onevpl | |
| } // namespace wip | |
| } // namespace gapi | |
| } // namespace cv | |