// Copyright 2016 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef MEDIA_BASE_SUBSAMPLE_ENTRY_H_ #define MEDIA_BASE_SUBSAMPLE_ENTRY_H_ #include #include #include #include "media/base/media_export.h" namespace media { // The Common Encryption spec provides for subsample encryption, where portions // of a sample are set in cleartext. A SubsampleEntry specifies the number of // clear and encrypted bytes in each subsample. For decryption, all of the // encrypted bytes in a sample should be considered a single logical stream, // regardless of how they are divided into subsamples, and the clear bytes // should not be considered as part of decryption. This is logically equivalent // to concatenating all 'cypher_bytes' portions of subsamples, decrypting that // result, and then copying each byte from the decrypted block over the // position of the corresponding encrypted byte. struct SubsampleEntry { SubsampleEntry() : clear_bytes(0), cypher_bytes(0) {} SubsampleEntry(uint32_t clear_bytes, uint32_t cypher_bytes) : clear_bytes(clear_bytes), cypher_bytes(cypher_bytes) {} uint32_t clear_bytes; uint32_t cypher_bytes; }; // Verifies that |subsamples| correctly specifies a buffer of length // |input_size|. Returns false if the total of bytes specified in |subsamples| // does not match |input_size|. MEDIA_EXPORT bool VerifySubsamplesMatchSize( const std::vector& subsamples, size_t input_size); } // namespace media #endif // MEDIA_BASE_SUBSAMPLE_ENTRY_H_