gif.go 357 B

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  1. package imagemeta
  2. import (
  3. "io"
  4. )
  5. func DecodeGifMeta(r io.Reader) (Meta, error) {
  6. var tmp [10]byte
  7. _, err := io.ReadFull(r, tmp[:])
  8. if err != nil {
  9. return nil, err
  10. }
  11. return &meta{
  12. format: "gif",
  13. width: int(tmp[6]) + int(tmp[7])<<8,
  14. height: int(tmp[8]) + int(tmp[9])<<8,
  15. }, nil
  16. }
  17. func init() {
  18. RegisterFormat("GIF8?a", DecodeGifMeta)
  19. }