31 lines
1.2 KiB
C++
31 lines
1.2 KiB
C++
// Copyright 2016 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef SUBSAMPLE_ENTRY_H_
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#define SUBSAMPLE_ENTRY_H_
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#include <stdint.h>
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namespace media {
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// The Common Encryption spec provides for subsample encryption, where portions
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// of a sample are set in cleartext. A SubsampleEntry specifies the number of
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// clear and encrypted bytes in each subsample. For decryption, all of the
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// encrypted bytes in a sample should be considered a single logical stream,
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// regardless of how they are divided into subsamples, and the clear bytes
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// should not be considered as part of decryption. This is logically equivalent
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// to concatenating all 'cypher_bytes' portions of subsamples, decrypting that
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// result, and then copying each byte from the decrypted block over the
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// position of the corresponding encrypted byte.
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struct SubsampleEntry {
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SubsampleEntry() : clear_bytes(0), cypher_bytes(0) {}
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SubsampleEntry(uint32_t clear_bytes, uint32_t cypher_bytes)
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: clear_bytes(clear_bytes), cypher_bytes(cypher_bytes) {}
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uint32_t clear_bytes;
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uint32_t cypher_bytes;
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};
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} // namespace media
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#endif // SUBSAMPLE_ENTRY_H_
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