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#------------------------------------------------------------------------------
# $File: jpeg,v 1.32 2018/10/01 18:58:29 christos Exp $
# JPEG images
# SunOS 5.5.1 had
#
# 0 string \377\330\377\340 JPEG file
# 0 string \377\330\377\356 JPG file
#
# both of which turn into "JPEG image data" here.
#
0 beshort 0xffd8 JPEG image data
!:mime image/jpeg
!:apple 8BIMJPEG
!:strength *3
!:ext jpeg/jpg/jpe/jfif
>6 string JFIF \b, JFIF standard
# The following added by Erik Rossen <rossen@freesurf.ch> 1999-09-06
# in a vain attempt to add image size reporting for JFIF. Note that these
# tests are not fool-proof since some perfectly valid JPEGs are currently
# impossible to specify in magic(4) format.
# First, a little JFIF version info:
>>11 byte x \b %d.
>>12 byte x \b%02d
# Next, the resolution or aspect ratio of the image:
>>13 byte 0 \b, aspect ratio
>>13 byte 1 \b, resolution (DPI)
>>13 byte 2 \b, resolution (DPCM)
>>14 beshort x \b, density %dx
>>16 beshort x \b%d
>>4 beshort x \b, segment length %d
# Next, show thumbnail info, if it exists:
>>18 byte !0 \b, thumbnail %dx
>>>19 byte x \b%d
>6 string Exif \b, Exif standard: [
>>12 indirect/r x
>>12 string x \b]
# Jump to the first segment
>(4.S+4) use jpeg_segment
# This uses recursion...
0 name jpeg_segment
>0 beshort 0xFFFE
# Recursion handled by FFE0
#>>(2.S+2) use jpeg_segment
>>2 pstring/HJ x \b, comment: "%s"
>0 beshort 0xFFC0
>>(2.S+2) use jpeg_segment
>>4 byte x \b, baseline, precision %d
>>7 beshort x \b, %dx
>>5 beshort x \b%d
>>9 byte x \b, components %d
>0 beshort 0xFFC1
>>(2.S+2) use jpeg_segment
>>4 byte x \b, extended sequential, precision %d
>>7 beshort x \b, %dx
>>5 beshort x \b%d
>>9 byte x \b, components %d
>0 beshort 0xFFC2
>>(2.S+2) use jpeg_segment
>>4 byte x \b, progressive, precision %d
>>7 beshort x \b, %dx
>>5 beshort x \b%d
>>9 byte x \b, components %d
# Define Huffman Tables
>0 beshort 0xFFC4
>>(2.S+2) use jpeg_segment
>0 beshort 0xFFE1
# Recursion handled by FFE0
#>>(2.S+2) use jpeg_segment
>>4 string Exif \b, Exif Standard: [
>>>10 indirect/r x
>>>10 string x \b]
# Application specific markers
>0 beshort&0xFFE0 =0xFFE0
>>(2.S+2) use jpeg_segment
# DB: Define Quantization tables
# DD: Define Restart interval [XXX: wrong here, it is 4 bytes]
# D8: Start of image
# D9: End of image
# Dn: Restart
>0 beshort&0xFFD0 =0xFFD0
>>0 beshort&0xFFE0 !0xFFE0
>>>(2.S+2) use jpeg_segment
#>0 beshort x unknown 0x%x
#>>(2.S+2) use jpeg_segment
# HSI is Handmade Software's proprietary JPEG encoding scheme
0 string hsi1 JPEG image data, HSI proprietary
# From: David Santinoli <david@santinoli.com>
0 string \x00\x00\x00\x0C\x6A\x50\x20\x20\x0D\x0A\x87\x0A JPEG 2000
# From: Johan van der Knijff <johan.vanderknijff@kb.nl>
# Added sub-entries for JP2, JPX, JPM and MJ2 formats; added mimetypes
# https://github.com/bitsgalore/jp2kMagic
#
# Now read value of 'Brand' field, which yields a few possibilities:
>20 string \x6a\x70\x32\x20 Part 1 (JP2)
!:mime image/jp2
>20 string \x6a\x70\x78\x20 Part 2 (JPX)
!:mime image/jpx
>20 string \x6a\x70\x6d\x20 Part 6 (JPM)
!:mime image/jpm
>20 string \x6d\x6a\x70\x32 Part 3 (MJ2)
!:mime video/mj2
# Type: JPEG 2000 codesream
# From: Mathieu Malaterre <mathieu.malaterre@gmail.com>
0 belong 0xff4fff51 JPEG 2000 codestream
45 beshort 0xff52
# JPEG extended range
0 string \x49\x49\xbc
>3 byte 1
>>4 lelong%2 0 JPEG-XR
!:mime image/jxr
!:ext jxr
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