52 lines
1.5 KiB
C++
52 lines
1.5 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
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*
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* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/**
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* Deinterlacer is a utility class to allow Downscaler to work with interlaced
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* images.
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* Since Downscaler needs to receive rows in top-to-bottom or
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* bottom-to-top order, it can't natively handle interlaced images, in which the
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* rows arrive in an interleaved order. Deinterlacer solves this problem by
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* acting as an intermediate buffer that records decoded rows. Unlike
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* Downscaler, it allows the rows to be written in arbitrary order. After each
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* pass, calling PropagatePassToDownscaler() will downscale every buffered row
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* in a single operation. The rows remain in the buffer, so rows that were
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* written in one pass will be included in subsequent passes.
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*/
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#ifndef mozilla_image_Deinterlacer_h
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#define mozilla_image_Deinterlacer_h
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#include "Downscaler.h"
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namespace mozilla {
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namespace image {
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class Deinterlacer
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{
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public:
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explicit Deinterlacer(const nsIntSize& aImageSize);
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bool IsValid() { return !!mBuffer; }
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uint8_t* RowBuffer(uint32_t aRow);
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void PropagatePassToDownscaler(Downscaler& aDownscaler);
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private:
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uint32_t RowSize() const;
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nsIntSize mImageSize;
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UniquePtr<uint8_t[]> mBuffer;
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};
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} // namespace image
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} // namespace mozilla
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#endif // mozilla_image_Deinterlacer_h
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