isJpg static method

Future<bool> isJpg(
  1. AsyncImageInput input
)

Implementation

static Future<bool> isJpg(AsyncImageInput input) async {
  if (!(await input.exists())) {
    return false;
  }

  const start = [0xFF, 0xD8];
  const end = [0xFF, 0xD9];

  final length = await input.length;
  final startList = await input.getRange(0, 2);
  final endList = await input.getRange(length - 2, length);

  const eq = ListEquality();

  return eq.equals(start, startList) && eq.equals(end, endList);
}