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<title>PNG Tags</title>
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<h2 class=top>PNG Tags</h2>
<blockquote>
<table class=frame><tr><td>
<table class=inner cellspacing=1>
<tr class=h><th>Tag ID</th><th>Tag Name</th>
<th>Writable</th><th>Values / <span class=n>Notes</span></th></tr>
<tr>
<td>'IHDR'</td>
<td>ImageHeader</td>
<td class=c>-</td>
<td>--> <a href='PNG.html#ImageHeader'>PNG ImageHeader Tags</a></td></tr>
<tr class=b>
<td>'PLTE'</td>
<td>Palette</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td>'bKGD'</td>
<td>BackgroundColor</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td>'cHRM'</td>
<td>PrimaryChromaticities</td>
<td class=c>-</td>
<td>--> <a href='PNG.html#PrimaryChromaticities'>PNG PrimaryChromaticities Tags</a></td></tr>
<tr>
<td>'fRAc'</td>
<td>FractalParameters</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td>'gAMA'</td>
<td>Gamma</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td>'gIFg'</td>
<td>GIFGraphicControlExtension</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td>'gIFt'</td>
<td>GIFPlainTextExtension</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td>'gIFx'</td>
<td>GIFApplicationExtension</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td>'hIST'</td>
<td>PaletteHistogram</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td>'iCCP'</td>
<td>ICC_Profile</td>
<td class=c>-</td>
<td>--> <a href='ICC_Profile.html'>ICC_Profile Tags</a></td></tr>
<tr class=b>
<td>'iTXt'</td>
<td>InternationalText</td>
<td class=c>-</td>
<td>--> <a href='PNG.html#TextualData'>PNG TextualData Tags</a></td></tr>
<tr>
<td>'oFFs'</td>
<td>ImageOffset</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td>'pCAL'</td>
<td>PixelCalibration</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td>'pHYs'</td>
<td>PhysicalPixel</td>
<td class=c>-</td>
<td>--> <a href='PNG.html#PhysicalPixel'>PNG PhysicalPixel Tags</a></td></tr>
<tr class=b>
<td>'sBIT'</td>
<td>SignificantBits</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td>'sPLT'</td>
<td>SuggestedPalette</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td>'sRGB'</td>
<td>SRGBRendering</td>
<td class=c>N</td>
<td><span class=s>0 = Perceptual
<br>1 = Relative Colorimetric
<br>2 = Saturation
<br>3 = Absolute Colorimetric</span></td></tr>
<tr>
<td>'tEXt'</td>
<td>TextualData</td>
<td class=c>-</td>
<td>--> <a href='PNG.html#TextualData'>PNG TextualData Tags</a></td></tr>
<tr class=b>
<td>'tIME'</td>
<td>ModifyDate</td>
<td class=c>Y</td>
<td> </td></tr>
<tr>
<td>'tRNS'</td>
<td>Transparency</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td>'tXMP'</td>
<td>XMP</td>
<td class=c>-</td>
<td>--> <a href='XMP.html'>XMP Tags</a>
<br><span class='n s'>(obsolete location specified by older XMP draft)</span></td></tr>
<tr>
<td>'zTXt'</td>
<td>CompressedText</td>
<td class=c>-</td>
<td>--> <a href='PNG.html#TextualData'>PNG TextualData Tags</a></td></tr>
</table></td></tr></table></blockquote>
<h2><a name='ImageHeader'>PNG ImageHeader Tags</a></h2>
<blockquote>
<table class=frame><tr><td>
<table class=inner cellspacing=1>
<tr class=h><th>Index</th><th>Tag Name</th>
<th>Writable</th><th>Values / <span class=n>Notes</span></th></tr>
<tr>
<td class=r title='0 = 0x0'>0</td>
<td>ImageWidth</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td class=r title='4 = 0x4'>4</td>
<td>ImageHeight</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td class=r title='8 = 0x8'>8</td>
<td>BitDepth</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td class=r title='9 = 0x9'>9</td>
<td>ColorType</td>
<td class=c>N</td>
<td><span class=s>0 = Grayscale
<br>2 = RGB
<br>3 = Palette
<br>4 = Grayscale with Alpha
<br>6 = RGB with Alpha</span></td></tr>
<tr>
<td class=r title='10 = 0xa'>10</td>
<td>Compression</td>
<td class=c>N</td>
<td><span class=s>0 = Deflate/Inflate</span></td></tr>
<tr class=b>
<td class=r title='11 = 0xb'>11</td>
<td>Filter</td>
<td class=c>N</td>
<td><span class=s>0 = Adaptive</span></td></tr>
<tr>
<td class=r title='12 = 0xc'>12</td>
<td>Interlace</td>
<td class=c>N</td>
<td><span class=s>0 = Noninterlaced
<br>1 = Adam7 Interlace</span></td></tr>
</table></td></tr></table></blockquote>
<h2><a name='PrimaryChromaticities'>PNG PrimaryChromaticities Tags</a></h2>
<blockquote>
<table class=frame><tr><td>
<table class=inner cellspacing=1>
<tr class=h><th>Index</th><th>Tag Name</th>
<th>Writable</th><th>Values / <span class=n>Notes</span></th></tr>
<tr>
<td class=r title='0 = 0x0'>0</td>
<td>WhitePointX</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td class=r title='1 = 0x1'>1</td>
<td>WhitePointY</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td class=r title='2 = 0x2'>2</td>
<td>RedX</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td class=r title='3 = 0x3'>3</td>
<td>RedY</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td class=r title='4 = 0x4'>4</td>
<td>GreenX</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td class=r title='5 = 0x5'>5</td>
<td>GreenY</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td class=r title='6 = 0x6'>6</td>
<td>BlueX</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td class=r title='7 = 0x7'>7</td>
<td>BlueY</td>
<td class=c>N</td>
<td> </td></tr>
</table></td></tr></table></blockquote>
<h2><a name='TextualData'>PNG TextualData Tags</a></h2>
<p>The PNG TextualData format allows aribrary tag names to be used. The tags
listed below are the only ones that can be written (unless new user-defined
tags are added via the configuration file), however ExifTool will extract
any other TextualData tags that are found.</p>
<p>Data for the TextualData tags may be stored as tEXt, zTXt or iTXt chunks in
the PNG image. ExifTool will read and edit tags in their original form, but
new string tags are created as uncompressed tEXt by default, or as
compressed zTXt if the -z (Compress) option is used and Compress::Zlib is
available. Raw profile information is always created as compressed zTXt if
Compress::Zlib is available.</p>
<p>Some of the tags below are not registered as part of the PNG specification,
but are included here because they are generated by other software such as
ImageMagick.</p>
<blockquote>
<table class=frame><tr><td>
<table class=inner cellspacing=1>
<tr class=h><th>Tag ID</th><th>Tag Name</th>
<th>Writable</th><th>Values / <span class=n>Notes</span></th></tr>
<tr>
<td>'Artist'</td>
<td>Artist</td>
<td class=c>string</td>
<td><span class=s><span class=n>(unregistered)</span></span></td></tr>
<tr class=b>
<td>'Author'</td>
<td>Author</td>
<td class=c>string</td>
<td> </td></tr>
<tr>
<td>'Comment'</td>
<td>Comment</td>
<td class=c>string</td>
<td> </td></tr>
<tr class=b>
<td>'Copyright'</td>
<td>Copyright</td>
<td class=c>string</td>
<td> </td></tr>
<tr>
<td>'Creation Time'</td>
<td>CreationTime</td>
<td class=c>string</td>
<td> </td></tr>
<tr class=b>
<td>'Description'</td>
<td>Description</td>
<td class=c>string</td>
<td> </td></tr>
<tr>
<td>'Disclaimer'</td>
<td>Disclaimer</td>
<td class=c>string</td>
<td> </td></tr>
<tr class=b>
<td>'Document'</td>
<td>Document</td>
<td class=c>string</td>
<td><span class=s><span class=n>(unregistered)</span></span></td></tr>
<tr>
<td>'Label'</td>
<td>Label</td>
<td class=c>string</td>
<td><span class=s><span class=n>(unregistered)</span></span></td></tr>
<tr class=b>
<td>'Make'</td>
<td>Make</td>
<td class=c>string</td>
<td><span class=s><span class=n>(unregistered)</span></span></td></tr>
<tr>
<td>'Model'</td>
<td>Model</td>
<td class=c>string</td>
<td><span class=s><span class=n>(unregistered)</span></span></td></tr>
<tr class=b>
<td>'Raw profile type APP1'</td>
<td>APP1_Profile</td>
<td class=c>-</td>
<td>--> <a href='EXIF.html'>EXIF Tags</a>
<br>--> <a href='XMP.html'>XMP Tags</a></td></tr>
<tr>
<td>'Raw profile type exif'</td>
<td>EXIF_Profile</td>
<td class=c>-</td>
<td>--> <a href='EXIF.html'>EXIF Tags</a></td></tr>
<tr class=b>
<td>'Raw profile type icc'</td>
<td>ICC_Profile</td>
<td class=c>-</td>
<td>--> <a href='ICC_Profile.html'>ICC_Profile Tags</a></td></tr>
<tr>
<td>'Raw profile type icm'</td>
<td>ICC_Profile</td>
<td class=c>-</td>
<td>--> <a href='ICC_Profile.html'>ICC_Profile Tags</a></td></tr>
<tr class=b>
<td>'Raw profile type iptc'</td>
<td>IPTC_Profile</td>
<td class=c>-</td>
<td>--> <a href='Photoshop.html'>Photoshop Tags</a></td></tr>
<tr>
<td>'Raw profile type xmp'</td>
<td>XMP_Profile</td>
<td class=c>-</td>
<td>--> <a href='XMP.html'>XMP Tags</a></td></tr>
<tr class=b>
<td>'Software'</td>
<td>Software</td>
<td class=c>string</td>
<td> </td></tr>
<tr>
<td>'Source'</td>
<td>Source</td>
<td class=c>string</td>
<td> </td></tr>
<tr class=b>
<td>'TimeStamp'</td>
<td>TimeStamp</td>
<td class=c>string</td>
<td><span class=s><span class=n>(unregistered)</span></span></td></tr>
<tr>
<td>'Title'</td>
<td>Title</td>
<td class=c>string</td>
<td> </td></tr>
<tr class=b>
<td>'URL'</td>
<td>URL</td>
<td class=c>string</td>
<td><span class=s><span class=n>(unregistered)</span></span></td></tr>
<tr>
<td>'Warning'</td>
<td>PNGWarning</td>
<td class=c>string</td>
<td> </td></tr>
<tr class=b>
<td>'XML:com.adobe.xmp'</td>
<td>XMP</td>
<td class=c>-</td>
<td>--> <a href='XMP.html'>XMP Tags</a>
<br><span class='n s'>(location according to the XMP specification -- this is where ExifTool will
add a new XMP chunk if the image didn't already contain XMP)</span></td></tr>
</table></td></tr></table></blockquote>
<h2><a name='PhysicalPixel'>PNG PhysicalPixel Tags</a></h2>
<blockquote>
<table class=frame><tr><td>
<table class=inner cellspacing=1>
<tr class=h><th>Index</th><th>Tag Name</th>
<th>Writable</th><th>Values / <span class=n>Notes</span></th></tr>
<tr>
<td class=r title='0 = 0x0'>0</td>
<td>PixelsPerUnitX</td>
<td class=c>N</td>
<td> </td></tr>
<tr class=b>
<td class=r title='4 = 0x4'>4</td>
<td>PixelsPerUnitY</td>
<td class=c>N</td>
<td> </td></tr>
<tr>
<td class=r title='8 = 0x8'>8</td>
<td>PixelUnits</td>
<td class=c>N</td>
<td><span class=s>0 = Unknown
<br>1 = Meters</span></td></tr>
</table></td></tr></table></blockquote>
<hr>
(This document generated automatically by Image::ExifTool::BuildTagLookup)
<br><i>Last revised Nov 14, 2007</i>
<p class=lf><a href='index.html'><-- ExifTool Tag Names</a></p>
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