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https://github.com/wader/fq.git
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e9d9f8aef9
Rename s/interface{}/any/g Preparation for using generics in decode API and native jq funcations etc Remove some unused linter ignores as linter has been fixed
48 lines
1.0 KiB
Go
48 lines
1.0 KiB
Go
package mpeg
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import (
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"github.com/wader/fq/pkg/decode"
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)
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func annexBFindStartCode(d *decode.D) (int64, int64, error) {
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offset, v, err := d.TryPeekFind(32, 8, -1, func(v uint64) bool {
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return annexBDecodeStartCodeLen(v) > 0
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})
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return offset, annexBDecodeStartCodeLen(v), err
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}
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func annexBDecodeStartCodeLen(v uint64) int64 {
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switch {
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case v == 0x00_00_00_01:
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return 4 * 8
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case v&0xff_ff_ff_00 == 0x00_00_01_00:
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return 3 * 8
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default:
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return 0
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}
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}
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func annexBDecode(d *decode.D, _ any, format decode.Group) any {
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currentOffset, currentPrefixLen, err := annexBFindStartCode(d)
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// TODO: really restrict to 0?
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if err != nil || currentOffset != 0 {
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d.Errorf("could not find start code (first)")
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}
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for d.NotEnd() {
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d.FieldRawLen("start_code", currentPrefixLen)
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nextOffset, nextPrefixLen, err := annexBFindStartCode(d)
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if err != nil {
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nextOffset = d.Len() - d.Pos()
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}
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naluLen := nextOffset
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d.FieldFormatLen("nalu", naluLen, format, nil)
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currentPrefixLen = nextPrefixLen
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}
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return nil
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}
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