48 lines
1.0 KiB
Go
48 lines
1.0 KiB
Go
// Copyright 2018 kts of kettek / Ketchetwahmeegwun Tecumseh Southall. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package apng
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import (
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"image"
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)
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// dispose_op values, as per the APNG spec.
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const (
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DISPOSE_OP_NONE = 0
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DISPOSE_OP_BACKGROUND = 1
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DISPOSE_OP_PREVIOUS = 2
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)
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// blend_op values, as per the APNG spec.
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const (
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BLEND_OP_SOURCE = 0
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BLEND_OP_OVER = 1
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)
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type Frame struct {
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Image image.Image
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width, height int
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XOffset, YOffset int
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DelayNumerator uint16
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DelayDenominator uint16
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DisposeOp byte
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BlendOp byte
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// IsDefault indicates if the Frame is a default image that
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// should not be used in the animation. IsDefault can only
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// be true on the first frame.
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IsDefault bool
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}
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// GetDelay returns the number of seconds in the frame.
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func (f *Frame) GetDelay() float64 {
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d := uint16(0)
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if f.DelayDenominator == 0 {
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d = 100
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} else {
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d = f.DelayDenominator
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}
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return float64(f.DelayNumerator) / float64(d)
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}
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