Hi Ralf, I haven't experimented with jpegs and osgdem for several years so it's due a revist. Adding more compression options into VPB will be required, including the option to write to .ive with compression jpegs.
One thing to note, using jpegs should reduce the memory footprint, but will take more CPU time to decompression, will also prevent the use of mipmaps so these will have to be generated by either the CPU or the GPU, and also being uncompressed in main memory will mean uncompressed when you download to GPU, pushing the CPU->GPU bandwidth, pushing the GPU memory as well. Given all of this, I'd expect using jpeg to produce better download rates over the internet, but it'll be a heavier load on CPU and GPU so frame drops will be more likely. Robert. On Sun, Aug 24, 2008 at 10:25 AM, Ralf Stokholm <[EMAIL PROTECTED]> wrote: > Arrrgh sry > > On a rare occasion of brain activity i checked the timestamp on the jpeg > plug in i build with the changed default quality and somehow my build must > have failed. > > It now builds much more compressed jpeg's :-) > > The question that remains is how to channel the desired compression through > vpb to the writer plug in because my command line doesn't seam to work. > > Additionally osg doesn't seam to work as an output, only the top level > texture is shown i guess its because vpb was changed to use sub folders but > the jpegs are all pleased in the root. This is not a big issue though as I > just checked that the jpegs can be embedded in the ive's as well. > > Gotta try to build a new terrain and test the paging performance of a > database build with jpeg's > > Brgs. > > Ralf Stokholm > Arenalogic > > 2008/8/24 Ralf Stokholm <[EMAIL PROTECTED]> >> >> Hi Robert >> >> Had some time to revisit this, and as you suggested is is possible to >> change the format of imagery generated if outputting to osg format. >> >> I tried the --image-ext jpeg option and it generated jpg files as >> expected, but to my surprise the generated output was larger than a similar >> dds output. >> >> I then spend some hours looking for creation options in the jpeg plug in >> and found the JPEG_QUALITY option. But it didn't do anything. >> >> This command line: >> vpbmaster -t input_vrt -l 4 --build-options "JPEG_QUALITY 20" --image-ext >> jpeg -o dk2\dk.osg >> >> results in a database of exactly the same size as it was without the >> JPEG_QUALITY option. >> >> I even tried leaving it at default and then recompile the jpeg plugin to >> use 20 as default quality in place of 100, that didn't change anything >> either. >> >> Can you give me any hints on how to make this work? >> >> Brgs. >> Ralf Stokholm >> Arenalogic >> >> >> 2008/8/3 Robert Osfield <[EMAIL PROTECTED]> >>> >>> Hi Ralf, >>> >>> osgdem does support changing the output format of the imagery, but it >>> may well need to be accompanied by outputting to .osg. I must admit >>> I haven't tested this specific feature during my work on >>> VirtualPlanetBuilder over the last year. Once OSG-2.6.0 is out I >>> should have a chance at revisiting this specific feature. >>> >>> Robert. >>> >>> On Wed, Jul 30, 2008 at 1:56 PM, Ralf Stokholm <[EMAIL PROTECTED]> >>> wrote: >>> > Hi Robert / all >>> > >>> > Thanks for the info on vpbmaster again, finally got around to trying it >>> > out. >>> > My data is in the ecw format and after some initial problems the trick >>> > about >>> > transforming them into vrt which is recommentet in another thread >>> > worked >>> > like a charm. >>> > >>> > Im currently building what will be a roughly 600 gig database 14 levels >>> > deep. I cant wait to see how it runs in my sim. :-) >>> > >>> > During my investigations I tried specifying different output formats >>> > like >>> > jpeg, I expected a jpeg database to be smaller than what is currently >>> > generatet, but it wassent. Is there no way of generating a database >>> > containing more compressed data than the default? I know it would >>> > propably >>> > hurt paging performance, but it might be worth it in may case. >>> > >>> > Brgs. >>> > >>> > Ralf >>> > _______________________________________________ >>> > osg-users mailing list >>> > osg-users@lists.openscenegraph.org >>> > >>> > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >>> > >>> > >>> _______________________________________________ >>> osg-users mailing list >>> osg-users@lists.openscenegraph.org >>> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >> > > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
