<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hello, <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I try to use GDAL to convert USGS Topo geopdfs to Geotiff format. I have the following command: <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>gdalwarp geo.pdf geo.tif -crop_to_cutline -cutline C:\JIANTestFolder\cutline.csv -overwrite --config GDAL_CACHEMAX 500 -wm 500 --config GDAL_PDF_LAYERS_OFF Projection_and_Grids --config GDAL_PDF_DPI 508 -co "TILED=YES" -co "TFW=YES" -co "COMPRESS=JPEG" –co "PHOTOMETRIC=YCBCR"<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I want to maintain the image quality while keeping the file to a minimal size. But my output .tif is about twice as big as the input pdf (19.5M vs. 11.9M) -- the output dpi (GDAL_PDF_DPI=508) is set based on the metadata information in the geopdf. I read somewhere that pdf just stores image “as it is”, and I am wondering how come my geotiff is twice as big, even with the jpeg compression with the YCBCR option? Is it still possible to reduce its size? <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Here is the geopdf I use: <span style='color:black'><a href="http://ims.er.usgs.gov/gda_services/download?item_id=5998960">http://ims.er.usgs.gov/gda_services/download?item_id=5998960</a><o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’ve searched the mail archive and couldn’t find anything relevant. I appreciate any answers or suggestions about converting geopdf to geotiffs. Thank you! <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best regards, <o:p></o:p></p><p class=MsoNormal>Jian <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>