1 2#------------------------------------------------------------------------------ 3# $File: jpeg,v 1.29 2015/04/10 15:36:02 christos Exp $ 4# JPEG images 5# SunOS 5.5.1 had 6# 7# 0 string \377\330\377\340 JPEG file 8# 0 string \377\330\377\356 JPG file 9# 10# both of which turn into "JPEG image data" here. 11# 120 beshort 0xffd8 JPEG image data 13!:mime image/jpeg 14!:apple 8BIMJPEG 15!:strength *3 16!:ext jpeg/jpg/jpe/jfif 17>6 string JFIF \b, JFIF standard 18# The following added by Erik Rossen <rossen@freesurf.ch> 1999-09-06 19# in a vain attempt to add image size reporting for JFIF. Note that these 20# tests are not fool-proof since some perfectly valid JPEGs are currently 21# impossible to specify in magic(4) format. 22# First, a little JFIF version info: 23>>11 byte x \b %d. 24>>12 byte x \b%02d 25# Next, the resolution or aspect ratio of the image: 26>>13 byte 0 \b, aspect ratio 27>>13 byte 1 \b, resolution (DPI) 28>>13 byte 2 \b, resolution (DPCM) 29>>14 beshort x \b, density %dx 30>>16 beshort x \b%d 31>>4 beshort x \b, segment length %d 32# Next, show thumbnail info, if it exists: 33>>18 byte !0 \b, thumbnail %dx 34>>>19 byte x \b%d 35>6 string Exif \b, Exif standard: [ 36>>12 indirect/r x 37>>12 string x \b] 38 39# Jump to the first segment 40>(4.S+4) use jpeg_segment 41 42# This uses recursion... 430 name jpeg_segment 44>0 beshort 0xFFFE 45# Recursion handled by FFE0 46#>>(2.S+2) use jpeg_segment 47>>2 pstring/HJ x \b, comment: "%s" 48 49>0 beshort 0xFFC0 50>>(2.S+2) use jpeg_segment 51>>4 byte x \b, baseline, precision %d 52>>7 beshort x \b, %dx 53>>5 beshort x \b%d 54>>9 byte x \b, frames %d 55 56>0 beshort 0xFFC1 57>>(2.S+2) use jpeg_segment 58>>4 byte x \b, extended sequential, precision %d 59>>7 beshort x \b, %dx 60>>5 beshort x \b%d 61>>9 byte x \b, frames %d 62 63>0 beshort 0xFFC2 64>>(2.S+2) use jpeg_segment 65>>4 byte x \b, progressive, precision %d 66>>7 beshort x \b, %dx 67>>5 beshort x \b%d 68>>9 byte x \b, frames %d 69 70# Define Huffman Tables 71>0 beshort 0xFFC4 72>>(2.S+2) use jpeg_segment 73 74>0 beshort 0xFFE1 75# Recursion handled by FFE0 76#>>(2.S+2) use jpeg_segment 77>>4 string Exif \b, Exif Standard: [ 78>>>10 indirect/r x 79>>>10 string x \b] 80 81# Application specific markers 82>0 beshort&0xFFE0 =0xFFE0 83>>(2.S+2) use jpeg_segment 84 85# DB: Define Quantization tables 86# DD: Define Restart interval [XXX: wrong here, it is 4 bytes] 87# D8: Start of image 88# D9: End of image 89# Dn: Restart 90>0 beshort&0xFFD0 =0xFFD0 91>>0 beshort&0xFFE0 !0xFFE0 92>>>(2.S+2) use jpeg_segment 93 94#>0 beshort x unknown 0x%x 95#>>(2.S+2) use jpeg_segment 96 97# HSI is Handmade Software's proprietary JPEG encoding scheme 980 string hsi1 JPEG image data, HSI proprietary 99 100# From: David Santinoli <david@santinoli.com> 1010 string \x00\x00\x00\x0C\x6A\x50\x20\x20\x0D\x0A\x87\x0A JPEG 2000 102# From: Johan van der Knijff <johan.vanderknijff@kb.nl> 103# Added sub-entries for JP2, JPX, JPM and MJ2 formats; added mimetypes 104# https://github.com/bitsgalore/jp2kMagic 105# 106# Now read value of 'Brand' field, which yields a few possibilities: 107>20 string \x6a\x70\x32\x20 Part 1 (JP2) 108!:mime image/jp2 109>20 string \x6a\x70\x78\x20 Part 2 (JPX) 110!:mime image/jpx 111>20 string \x6a\x70\x6d\x20 Part 6 (JPM) 112!:mime image/jpm 113>20 string \x6d\x6a\x70\x32 Part 3 (MJ2) 114!:mime video/mj2 115 116# Type: JPEG 2000 codesream 117# From: Mathieu Malaterre <mathieu.malaterre@gmail.com> 1180 belong 0xff4fff51 JPEG 2000 codestream 11945 beshort 0xff52 120