1# $OpenBSD: jpeg,v 1.4 2009/04/24 18:54:34 chl Exp $ 2 3#------------------------------------------------------------------------------ 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>6 string JFIF \b, JFIF standard 15# The following added by Erik Rossen <rossen@freesurf.ch> 1999-09-06 16# in a vain attempt to add image size reporting for JFIF. Note that these 17# tests are not fool-proof since some perfectly valid JPEGs are currently 18# impossible to specify in magic(4) format. 19# First, a little JFIF version info: 20>>11 byte x \b %d. 21>>12 byte x \b%02d 22# Next, the resolution or aspect ratio of the image: 23#>>13 byte 0 \b, aspect ratio 24#>>13 byte 1 \b, resolution (DPI) 25#>>13 byte 2 \b, resolution (DPCM) 26#>>4 beshort x \b, segment length %d 27# Next, show thumbnail info, if it exists: 28>>18 byte !0 \b, thumbnail %dx 29>>>19 byte x \b%d 30 31# EXIF moved down here to avoid reporting a bogus version number, 32# and EXIF version number printing added. 33# - Patrik R=E5dman <patrik+file-magic@iki.fi> 34>6 string Exif \b, EXIF standard 35# Look for EXIF IFD offset in IFD 0, and then look for EXIF version tag in EXIF IFD. 36# All possible combinations of entries have to be enumerated, since no looping 37# is possible. And both endians are possible... 38# The combinations included below are from real-world JPEGs. 39# Little-endian 40>>12 string II 41# IFD 0 Entry #5: 42>>>70 leshort 0x8769 43# EXIF IFD Entry #1: 44>>>>(78.l+14) leshort 0x9000 45>>>>>(78.l+23) byte x %c 46>>>>>(78.l+24) byte x \b.%c 47>>>>>(78.l+25) byte !0x30 \b%c 48# IFD 0 Entry #9: 49>>>118 leshort 0x8769 50# EXIF IFD Entry #3: 51>>>>(126.l+38) leshort 0x9000 52>>>>>(126.l+47) byte x %c 53>>>>>(126.l+48) byte x \b.%c 54>>>>>(126.l+49) byte !0x30 \b%c 55# IFD 0 Entry #10 56>>>130 leshort 0x8769 57# EXIF IFD Entry #3: 58>>>>(138.l+38) leshort 0x9000 59>>>>>(138.l+47) byte x %c 60>>>>>(138.l+48) byte x \b.%c 61>>>>>(138.l+49) byte !0x30 \b%c 62# EXIF IFD Entry #4: 63>>>>(138.l+50) leshort 0x9000 64>>>>>(138.l+59) byte x %c 65>>>>>(138.l+60) byte x \b.%c 66>>>>>(138.l+61) byte !0x30 \b%c 67# EXIF IFD Entry #5: 68>>>>(138.l+62) leshort 0x9000 69>>>>>(138.l+71) byte x %c 70>>>>>(138.l+72) byte x \b.%c 71>>>>>(138.l+73) byte !0x30 \b%c 72# IFD 0 Entry #11 73>>>142 leshort 0x8769 74# EXIF IFD Entry #3: 75>>>>(150.l+38) leshort 0x9000 76>>>>>(150.l+47) byte x %c 77>>>>>(150.l+48) byte x \b.%c 78>>>>>(150.l+49) byte !0x30 \b%c 79# EXIF IFD Entry #4: 80>>>>(150.l+50) leshort 0x9000 81>>>>>(150.l+59) byte x %c 82>>>>>(150.l+60) byte x \b.%c 83>>>>>(150.l+61) byte !0x30 \b%c 84# EXIF IFD Entry #5: 85>>>>(150.l+62) leshort 0x9000 86>>>>>(150.l+71) byte x %c 87>>>>>(150.l+72) byte x \b.%c 88>>>>>(150.l+73) byte !0x30 \b%c 89# Big-endian 90>>12 string MM 91# IFD 0 Entry #9: 92>>>118 beshort 0x8769 93# EXIF IFD Entry #1: 94>>>>(126.L+14) beshort 0x9000 95>>>>>(126.L+23) byte x %c 96>>>>>(126.L+24) byte x \b.%c 97>>>>>(126.L+25) byte !0x30 \b%c 98# EXIF IFD Entry #3: 99>>>>(126.L+38) beshort 0x9000 100>>>>>(126.L+47) byte x %c 101>>>>>(126.L+48) byte x \b.%c 102>>>>>(126.L+49) byte !0x30 \b%c 103# IFD 0 Entry #10 104>>>130 beshort 0x8769 105# EXIF IFD Entry #3: 106>>>>(138.L+38) beshort 0x9000 107>>>>>(138.L+47) byte x %c 108>>>>>(138.L+48) byte x \b.%c 109>>>>>(138.L+49) byte !0x30 \b%c 110# EXIF IFD Entry #5: 111>>>>(138.L+62) beshort 0x9000 112>>>>>(138.L+71) byte x %c 113>>>>>(138.L+72) byte x \b.%c 114>>>>>(138.L+73) byte !0x30 \b%c 115# IFD 0 Entry #11 116>>>142 beshort 0x8769 117# EXIF IFD Entry #4: 118>>>>(150.L+50) beshort 0x9000 119>>>>>(150.L+59) byte x %c 120>>>>>(150.L+60) byte x \b.%c 121>>>>>(150.L+61) byte !0x30 \b%c 122# Here things get sticky. We can do ONE MORE marker segment with 123# indirect addressing, and that's all. It would be great if we could 124# do pointer arithemetic like in an assembler language. Christos? 125# And if there was some sort of looping construct to do searches, plus a few 126# named accumulators, it would be even more effective... 127# At least we can show a comment if no other segments got inserted before: 128>(4.S+5) byte 0xFE 129>>(4.S+8) string >\0 \b, comment: "%s" 130#>(4.S+5) byte 0xFE \b, comment 131#>>(4.S+6) beshort x \b length=%d 132#>>(4.S+8) string >\0 \b, "%s" 133# Or, we can show the encoding type (I've included only the three most common) 134# and image dimensions if we are lucky and the SOFn (image segment) is here: 135>(4.S+5) byte 0xC0 \b, baseline 136>>(4.S+6) byte x \b, precision %d 137>>(4.S+7) beshort x \b, %dx 138>>(4.S+9) beshort x \b%d 139>(4.S+5) byte 0xC1 \b, extended sequential 140>>(4.S+6) byte x \b, precision %d 141>>(4.S+7) beshort x \b, %dx 142>>(4.S+9) beshort x \b%d 143>(4.S+5) byte 0xC2 \b, progressive 144>>(4.S+6) byte x \b, precision %d 145>>(4.S+7) beshort x \b, %dx 146>>(4.S+9) beshort x \b%d 147# I've commented-out quantisation table reporting. I doubt anyone cares yet. 148#>(4.S+5) byte 0xDB \b, quantisation table 149#>>(4.S+6) beshort x \b length=%d 150#>14 beshort x \b, %d x 151#>16 beshort x \b %d 152 153# HSI is Handmade Software's proprietary JPEG encoding scheme 1540 string hsi1 JPEG image data, HSI proprietary 155 156# From: David Santinoli <david@santinoli.com> 1570 string \x00\x00\x00\x0C\x6A\x50\x20\x20\x0D\x0A\x87\x0A JPEG 2000 image data 158 159# Type: JPEG 2000 codesream 160# From: Mathieu Malaterre <mathieu.malaterre@gmail.com> 1610 belong 0xff4fff51 JPEG 2000 codestream 16245 beshort 0xff52 163