Need help with TIF TILE SIZE

[Brent Fraser]

Yar,

  It would be something like:

gdalwarp -s_srs "+proj=utm +zone=15 +datum=NAD83" -t_srs "+proj=latlong
+datum=WGS84" 10_1_1.tif latlong.tif

Then do 4 more gdalwarps of the surrounding files into the same target
file to fill in the edges.  For example:

gdalwarp -s_srs "+proj=utm +zone=15 +datum=NAD83" 10_1_2.tif latlong.tif
gdalwarp -s_srs "+proj=utm +zone=15 +datum=NAD83" 10_1_3.tif latlong.tif
gdalwarp -s_srs "+proj=utm +zone=15 +datum=NAD83" 10_1_4.tif latlong.tif
gdalwarp -s_srs "+proj=utm +zone=15 +datum=NAD83" 10_1_5.tif latlong.tif

Note the -t_srs is not allowed after the first gdalwarp command.

Brent

> Brent,
>
> Thank you.
>
> Would you happen to have a sample syntax for the mosaicking feature of
> gdalwarp?
>
>
> Yar
>
>
>
> On Thu, 7 Jul 2005 08:21:28 -0600, Brent Fraser <bfraser at GEOANALYTIC.COM>
> wrote:
>
>>Yar,
>>
>>  The effect you are seeing may be due to re-projecting the UTM tifs to
>>geographic (latlong).  This results in having a set of nodata (usually
>>black) pixels around the perimeter of the new tif file.  One solution is
>> to
>>use the mosaicking feature of gdalwarp to add in the surrounding UTM
>> images
>>it fill in the gaps.
>>
>>Brent Fraser
>>
>>
>>----- Original Message -----
>>From: "Yar Doroshenko" <numerous at GMAIL.COM>
>>To: <MAPSERVER-USERS at LISTS.UMN.EDU>
>>Sent: Wednesday, July 06, 2005 9:08 PM
>>Subject: [UMN_MAPSERVER-USERS] Need help with TIF TILE SIZE
>>
>>
>>> Hi Guys,
>>>
>>> Would anyone be able to answer this one, I'm posting it second time:
>>>
>>> My tileindex works fine, I have 51 tig images, I define my layer as the
>>> folowing:
>>>
>>> layer
>>> name "aerial"
>>> tileindex mrsid/img_index
>>> type raster
>>> status default
>>> end
>>>
>>> My tif images display just fine, the top left corner seems to be
>>positioned
>>> correctly. The problem is that at a certain zoom level, there are
>>> spaces
>>> between my tiles and I would like them to overlap. I know that my tifs
> are
>>> fine, when I open them in a viewer I can zoom in deep. Is there any way
> to
>>> make tifs larger, or make them overlap at a certain zoom level?
>>>
>>> Also, here is what I used before I implemented gdaltindex:
>>>
>>> I used mrsiddecode to convert my MrSID images to Tif
>>>
>>> mrsiddecode -i input.sid -o output.tif -s 2
>>>
>>> This way I got my tif to be around 100Mb instead of 2Gb with
>>gdal_translate
>>>
>>> next I did gdalwarp to convert my coordinates
>>>
>>> C:\ITS\GDAL\125\bin>gdalwarp -s_srs "+proj=utm +zone=15 +datum=NAD83" -
>>> t_srs "+p
>>> roj=latlong +datum=WGS84" 10_1_1.tif latlong.tif
>>> :0...10...20...30...40...50...60...70...80...90...100 - done.
>>>
>>>
>>> Could anyone see a potential explanation to my tile problem?
>>>
>>> Thank you,
>>>
>>>
>>> Yar
>