mirror of https://bitbucket.org/ausocean/av.git
65 lines
965 B
Go
65 lines
965 B
Go
/*
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DESCRIPTION
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helpers.go provides general helper utilities.
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AUTHORS
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Saxon Nelson-Milton <saxon@ausocean.org>, The Australian Ocean Laboratory (AusOcean)
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*/
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package h264dec
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import (
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"errors"
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)
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// binToSlice is a helper function to convert a string of binary into a
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// corresponding byte slice, e.g. "0100 0001 1000 1100" => {0x41,0x8c}.
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// Spaces in the string are ignored.
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func binToSlice(s string) ([]byte, error) {
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var (
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a byte = 0x80
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cur byte
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bytes []byte
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)
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for i, c := range s {
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switch c {
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case ' ':
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continue
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case '1':
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cur |= a
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case '0':
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default:
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return nil, errors.New("invalid binary string")
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}
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a >>= 1
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if a == 0 || i == (len(s)-1) {
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bytes = append(bytes, cur)
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cur = 0
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a = 0x80
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}
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}
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return bytes, nil
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}
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func maxi(a, b int) int {
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if a > b {
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return a
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}
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return b
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}
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func mini(a, b int) int {
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if a < b {
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return a
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}
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return b
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}
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func absi(a int) int {
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if a < 0 {
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return -a
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}
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return a
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}
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