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54 lines
1.1 KiB
Go
54 lines
1.1 KiB
Go
// Copyright 2021 The Periph Authors. All rights reserved.
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// Use of this source code is governed under the Apache License, Version 2.0
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// that can be found in the LICENSE file.
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package videosink
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import (
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"image/png"
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"sync"
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)
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type pngEncoderBufferPool sync.Pool
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func (p *pngEncoderBufferPool) Get() *png.EncoderBuffer {
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buf, _ := (*sync.Pool)(p).Get().(*png.EncoderBuffer)
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return buf
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}
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func (p *pngEncoderBufferPool) Put(buf *png.EncoderBuffer) {
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(*sync.Pool)(p).Put(buf)
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}
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type pngEncoderManager struct {
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mu sync.Mutex
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pool pngEncoderBufferPool
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enc map[png.CompressionLevel]*png.Encoder
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}
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var pngEncoder pngEncoderManager
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// get returns a PNG encoder with a globally shared buffer pool.
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func (m *pngEncoderManager) get(level png.CompressionLevel) *png.Encoder {
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m.mu.Lock()
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defer m.mu.Unlock()
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enc := m.enc[level]
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if enc == nil {
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if m.enc == nil {
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// The vast majority of use cases will involve exactly one
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// compression level.
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m.enc = make(map[png.CompressionLevel]*png.Encoder, 1)
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}
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enc = &png.Encoder{
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CompressionLevel: level,
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BufferPool: &m.pool,
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}
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m.enc[level] = enc
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}
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return enc
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}
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