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79 lines
1.5 KiB
Go
79 lines
1.5 KiB
Go
// +build !cgo
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package frame
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import (
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"fmt"
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"image"
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)
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func decodeYUY2(frame []byte, width, height int) (image.Image, func(), error) {
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yi := width * height
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ci := yi / 2
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fi := yi + 2*ci
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if len(frame) != fi {
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return nil, func() {}, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
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}
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y := make([]byte, yi)
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cb := make([]byte, ci)
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cr := make([]byte, ci)
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fast := 0
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slow := 0
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for i := 0; i < fi; i += 4 {
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y[fast] = frame[i]
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cb[slow] = frame[i+1]
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y[fast+1] = frame[i+2]
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cr[slow] = frame[i+3]
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fast += 2
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slow++
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}
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return &image.YCbCr{
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Y: y,
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YStride: width,
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Cb: cb,
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Cr: cr,
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CStride: width / 2,
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SubsampleRatio: image.YCbCrSubsampleRatio422,
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Rect: image.Rect(0, 0, width, height),
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}, func() {}, nil
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}
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func decodeUYVY(frame []byte, width, height int) (image.Image, func(), error) {
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yi := width * height
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ci := yi / 2
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fi := yi + 2*ci
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if len(frame) != fi {
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return nil, func() {}, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
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}
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y := make([]byte, yi)
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cb := make([]byte, ci)
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cr := make([]byte, ci)
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fast := 0
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slow := 0
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for i := 0; i < fi; i += 4 {
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cb[slow] = frame[i]
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y[fast] = frame[i+1]
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cr[slow] = frame[i+2]
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y[fast+1] = frame[i+3]
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fast += 2
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slow++
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}
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return &image.YCbCr{
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Y: y,
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YStride: width,
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Cb: cb,
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Cr: cr,
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CStride: width / 2,
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SubsampleRatio: image.YCbCrSubsampleRatio422,
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Rect: image.Rect(0, 0, width, height),
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}, func() {}, nil
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}
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