57 lines
1.0 KiB
Go
57 lines
1.0 KiB
Go
package mov
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import (
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"bytes"
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"encoding/binary"
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"errors"
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"io"
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"time"
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)
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const epochAdjust = 2082844800
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// Created attempts to find a created time from the metadata in a .mov file.
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func Created(file io.ReadSeeker) (time.Time, error) {
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var r time.Time
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var err error
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buf := [8]byte{}
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for {
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_, err := file.Read(buf[:])
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if err != nil {
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return r, err
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}
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if bytes.Equal(buf[4:8], []byte("moov")) {
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break
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} else {
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atomSize := binary.BigEndian.Uint32(buf[:])
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file.Seek(int64(atomSize)-8, 1)
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}
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}
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_, err = file.Read(buf[:])
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if err != nil {
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return r, err
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}
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s := string(buf[4:8])
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switch s {
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case "mvhd":
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if _, err := file.Seek(4, 1); err != nil {
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return r, err
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}
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_, err = file.Read(buf[:4])
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if err != nil {
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return r, err
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}
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i := int64(binary.BigEndian.Uint32(buf[:4]))
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c := i - epochAdjust
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u := time.Unix(c, 0).Local()
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return u, nil
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case "cmov":
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return r, errors.New("moov atom is compressed")
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default:
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return r, errors.New("expected to find 'mvhd' header, didn't")
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}
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}
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