Re: [gdal-dev] LJPEG Support for GDAL

2021-06-16 Thread bradh
I note that NITF JPEG is a bit different to what libjpeg puts out by default. See MIL-STD-188-198A.I would interested to see sample data with C5/M5 IC. What makes it?BradOn 17 Jun. 2021 04:07, Even Rouault wrote: Le 16/06/2021 à 19:53, GeodudeKid a écrit : > We can refer to this: https://en.wikipe

Re: [gdal-dev] LJPEG Support for GDAL

2021-06-16 Thread Christoph Gohlke
Lossless JPEG is defined in the Annex H of the JPEG specification. See also and . LJPEG compressed images ca

Re: [gdal-dev] LJPEG Support for GDAL

2021-06-16 Thread Even Rouault
Le 16/06/2021 à 19:53, GeodudeKid a écrit : We can refer to this: https://en.wikipedia.org/wiki/Lossless_JPEG. "Besides lossless compression, JPEG-LS also provides a lossy mode ("near-lossless") where the maximum absolute error can be controlled by the encoder." That being said, would the existi

Re: [gdal-dev] LJPEG Support for GDAL

2021-06-16 Thread GeodudeKid
We can refer to this: https://en.wikipedia.org/wiki/Lossless_JPEG. "Besides lossless compression, JPEG-LS also provides a lossy mode ("near-lossless") where the maximum absolute error can be controlled by the encoder." That being said, would the existing JPEGLS driver be able to support lossless an

Re: [gdal-dev] LJPEG Support for GDAL

2021-06-16 Thread Even Rouault
Hum, your answer confuses me. Do you have a pointer to where LJPEG is specified, and how different it is from JPEGLS ? Looking at MIL-STD-2500C (https://nsgreg.nga.mil/doc/view?i=4724&month=3&day=22&year=2021), it mentions C5 - Lossless JPEG C6 - reserved values that will represent a future

Re: [gdal-dev] LJPEG Support for GDAL

2021-06-16 Thread GeodudeKid
LJPEG is lossless JPEG. Trying to produce a NITF that is representative of the Image Compression (IC) field being set to C5 or C6. C5 should be for LJPEG, and C6 is for JPEGLS. I was wondering if there's a separate driver for lossless JPEG, or if JPEGLS is a catch-all for both compression algorithm

Re: [gdal-dev] LJPEG Support for GDAL

2021-06-16 Thread Even Rouault
What is exacly LJPEG ? Is it Lossless JPEG ? If so, you need the CharLS driver: https://gdal.org/drivers/raster/jpegls.html Le 16/06/2021 à 17:58, GeodudeKid a écrit : Is there an LJPEG driver for GDAL? I tried looking on the documentation online, but nothing really showed up. Has there been an

[gdal-dev] LJPEG Support for GDAL

2021-06-16 Thread GeodudeKid
Is there an LJPEG driver for GDAL? I tried looking on the documentation online, but nothing really showed up. Has there been anyone that has added support for LJPEG compression? -- Sent from: http://osgeo-org.1560.x6.nabble.com/GDAL-Dev-f3742093.html _