public static bool Read(string file, List <byte[]> byteSearch)
{
//var r1 = new ExifLib.ExifReader(file);
//var m1 = MetadataExtractor.ImageMetadataReader.ReadMetadata(file);
Console.Write("Searching " + file);
var fileBytes = System.IO.File.ReadAllBytes(file);
int indexOfMp4 = -1;
foreach (var search in byteSearch)
{
indexOfMp4 = new BoyerMoore(search).Search(fileBytes);
if (indexOfMp4 >= 0)
{
break;
}
}
if (indexOfMp4 >= 0)
{
Console.WriteLine(" Found the video");
WriteVideo(file, fileBytes, indexOfMp4);
return(true);
}
else
{
Console.Write(" Did not find known video, trying generic approach");
// http://dev.exiv2.org/projects/exiv2/wiki/The_Metadata_in_JPEG_files says that a JPEG start of image with 0xFFD8 and ends with 0xFFD9.
var endOfJpeg = MovingPhotoExtraction.ToBytes("FF D9".Split(' '));
var indexOfMp4_Part1 = MovingPhotoExtraction.ToBytes("00 00 00".Split(' '));
var indexOfMp4_Part2 = MovingPhotoExtraction.ToBytes("66 74 79 70".Split(' '));
var indexOfMp4_Part3 = MovingPhotoExtraction.ToBytes("6D 70 34 32".Split(' '));
var bm = new BoyerMoore(endOfJpeg);
var endOf = bm.Search(fileBytes);
bm.SetPattern(indexOfMp4_Part2);
var part2s = bm.SearchAll(fileBytes);
bm.SetPattern(indexOfMp4_Part3);
foreach (var part2 in part2s)
{
if (part2 < endOf)
{
Console.Write("Not yet at end of jpeg");
}
var part3 = bm.SearchAll(fileBytes).FirstOrDefault(a => a > part2);
// part 3 is just a bit further than part2
if (part3 > part2 && part2 + 20 > part3)
{
var minus4 = fileBytes[part2 - 4];
var minus3 = fileBytes[part2 - 3];
var minus2 = fileBytes[part2 - 2];
var minus1 = fileBytes[part2 - 1];
if (minus4 == 0 && minus3 == 0 && minus2 == 0)
{
Console.WriteLine("... Found video via pattern search");
WriteVideo(file, fileBytes, part2 - 4);
return(true);
}
Console.WriteLine($"... Found part2 and 3, not 1: {minus4} {minus3} {minus2} {minus1}");
}
}
Console.WriteLine($"Failed to find the video out of {part2s.Count} possibilites");
Console.WriteLine("Please report this output to https://github.com/cliveontoast/GoMoPho/issues and attach your moving image jpeg file");
}
return(false);
}
