Early width estimation of fragmented JPEG with corrupted header

In transformed and compressed domain fragmented files are very difficult to recover using conventional file recovery software. JPEG images are forensically important file format due to its popularity in a wide area of applications. In JPEG compression the header keeps important parameters that are required to decode the image back to pixel domain. In this paper the detection of width and height of an image from the JPEG stream is improved with less assumptions than previous papers. In the old approaches it was assumed that information about the image like Huffman table, Reset (RST) value and Quantization table were readily available for the techniques to work. However, in this paper the width is extracted from the quantized AC values that reduce the assumptions to just Huffman table.