Wireshark · Display Filter Reference: Portable Network Graphics

Field name	Description	Type	Versions
png.bkgd.blue	Blue	Unsigned integer (16 bits)	1.0.0 to 4.4.2
png.bkgd.green	Green	Unsigned integer (16 bits)	1.0.0 to 4.4.2
png.bkgd.greyscale	Greyscale	Unsigned integer (16 bits)	1.0.0 to 4.4.2
png.bkgd.palette_index	Palette Index	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.bkgd.red	Red	Unsigned integer (16 bits)	1.0.0 to 4.4.2
png.chrm.blue.x	Blue X	Floating point (single-precision)	1.12.0 to 4.4.2
png.chrm.blue.y	Blue Y	Floating point (single-precision)	1.12.0 to 4.4.2
png.chrm.green.x	Green X	Floating point (single-precision)	1.12.0 to 4.4.2
png.chrm.green.y	Green Y	Floating point (single-precision)	1.12.0 to 4.4.2
png.chrm.red.x	Red X	Floating point (single-precision)	1.12.0 to 4.4.2
png.chrm.red.y	Red Y	Floating point (single-precision)	1.12.0 to 4.4.2
png.chrm.white.x	White X	Floating point (single-precision)	1.12.0 to 4.4.2
png.chrm.white.y	White Y	Floating point (single-precision)	1.12.0 to 4.4.2
png.chunk.crc	CRC	Unsigned integer (32 bits)	1.0.0 to 4.4.2
png.chunk.data	Data	Label	1.0.0 to 4.4.2
png.chunk.flag.ancillary	Ancillary	Boolean	1.0.0 to 4.4.2
png.chunk.flag.private	Private	Boolean	1.0.0 to 4.4.2
png.chunk.flag.stc	Safe To Copy	Boolean	1.0.0 to 4.4.2
png.chunk.len	Len	Unsigned integer (32 bits)	1.0.0 to 4.4.2
png.chunk.type	Type	Character string	1.0.0 to 4.4.2
png.chunk_too_large	chunk size too large, dissection of this chunk is not supported	Label	1.12.0 to 4.4.2
png.gama.gamma	Gamma	Floating point (single-precision)	1.12.0 to 4.4.2
png.ihdr.bitdepth	Bit Depth	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.ihdr.colour_type	Colour Type	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.ihdr.compression_method	Compression Method	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.ihdr.filter_method	Filter Method	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.ihdr.height	Height	Unsigned integer (32 bits)	1.0.0 to 4.4.2
png.ihdr.interlace_method	Interlace Method	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.ihdr.width	Width	Unsigned integer (32 bits)	1.0.0 to 4.4.2
png.phys.horiz	Horizontal pixels per unit	Unsigned integer (32 bits)	1.0.0 to 4.4.2
png.phys.unit	Unit	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.phys.vert	Vertical pixels per unit	Unsigned integer (32 bits)	1.0.0 to 4.4.2
png.signature	PNG Signature	Byte sequence	1.0.0 to 4.4.2
png.srgb.intent	Intent	Unsigned integer (8 bits)	1.12.0 to 4.4.2
png.text.keyword	Keyword	Character string	1.0.0 to 4.4.2
png.text.string	String	Character string	1.0.0 to 4.4.2
png.time.day	Day	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.time.hour	Hour	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.time.minute	Minute	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.time.month	Month	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.time.second	Second	Unsigned integer (8 bits)	1.0.0 to 4.4.2
png.time.year	Year	Unsigned integer (16 bits)	1.0.0 to 4.4.2