#------------------------------------------------------------------------------ # $File: jpeg,v 1.31 2017/03/17 21:35:28 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, frames %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, frames %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, frames %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