isJpg static method
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);
}