Re: [gdal-dev] Create COG jpeg tiles with JFIF APPn markers
Jose, Those tiles contain normal JPEG markers (SOI, SOF0, DQT) but no JFIF marker (APP/n/) is added. How can I ensure adding this JFIF marker? you can't, unless you're ready to patch the JPEG codec in libtiff to do that I should point to https://www.awaresystems.be/imaging/tiff/specification/TIFFTechNote2.txt which mentions: "Writers should avoid including "noise" JPEG markers (COM and APPn markers). Standard TIFF fields provide a better way to transport any non-image data. Some JPEG codecs may change behavior if they see an APPn marker they think they understand; since the TIFF spec requires these markers to be ignored, this behavior is undesirable." Even -- http://www.spatialys.com My software is free, but my time generally not. ___ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev
Re: [gdal-dev] Create COG jpeg tiles with JFIF APPn markers
Hi, I would like to inform that you did write mail to the right place even you have not received any answers yet. Unfortunately your question is too specific for most GDAL users and capable developers are very busy as you can see from the GitHub activity. Let's still hope that somebody reacts. -Jukka Rahkonen- Lähettäjä: gdal-dev Puolesta Jose Calvo Lähetetty: tiistai 29. maaliskuuta 2022 9.59 Vastaanottaja: gdal-dev@lists.osgeo.org Aihe: [gdal-dev] Create COG jpeg tiles with JFIF APPn markers Hi. Currently my c++ app creates COG files from GeoTiff tiled files. GeoTiff files are created using JPEG compression with YCBCR photometric using following creation options: * PROFILE=GeoTIFF * TILED=YES * BLOCKXSIZE=xxx * BLOCKYSIZE=xxx * COMPRESS=JPEG * PHOTOMETRIC=YCBCR * JPEG_QUALITY=xx * JPEGTABLESMODE=0 >From this Geotiff files, app creates COG tiled files using following options: * BLOCKSIZE=xxx * OVERVIEWS=FORCE_USE_EXISTING * COMPRESS=JPEG * QUALITY=xx Those tiles contain normal JPEG markers (SOI, SOF0, DQT) but no JFIF marker (APPn) is added. How can I ensure adding this JFIF marker? I'm using gdal 3.1.0.7 in a ubuntu 20.10 using both strategies: * internal jpeg and tiff code: --with-jpeg=internal --with-libtiff=internal * external jpeg and tiff libraries: libjpeg.so.8.2.2 libtiff.so.5.5.0 Thanks in advance. ___ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev
[gdal-dev] Create COG jpeg tiles with JFIF APPn markers
Hi. Currently my c++ app creates COG files from GeoTiff tiled files. GeoTiff files are created using JPEG compression with YCBCR photometric using following creation options: * PROFILE=GeoTIFF * TILED=YES * BLOCKXSIZE=xxx * BLOCKYSIZE=xxx * COMPRESS=JPEG * PHOTOMETRIC=YCBCR * JPEG_QUALITY=xx * JPEGTABLESMODE=0 >From this Geotiff files, app creates COG tiled files using following options: * BLOCKSIZE=xxx * OVERVIEWS=FORCE_USE_EXISTING * COMPRESS=JPEG * QUALITY=xx Those tiles contain normal JPEG markers (SOI, SOF0, DQT) but no JFIF marker (APPn) is added. How can I ensure adding this JFIF marker? I'm using gdal 3.1.0.7 in a ubuntu 20.10 using both strategies: * internal jpeg and tiff code: --with-jpeg=internal --with-libtiff=internal * external jpeg and tiff libraries: libjpeg.so.8.2.2 libtiff.so.5.5.0 Thanks in advance. ___ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev
