|TIFF and LibTiff Mailing List Archive|
LibTiff Mailing List
2012.04.24 19:19 "Re: YCbCr/JPEG issue in 4.0.1", by Even Rouault
Le mardi 24 avril 2012 18:44:18, Frank Warmerdam a écrit : > John, > > It sounds like you ought to file a ticket on this. It may be that > the changed behavior is intentional. If the tag isn't really there > but is deduced for processing it may be that it is not considered > desirable to expose it as if it were really a tag. http://partners.adobe.com/public/developer/en/tiff/TIFF6.pdf shows that the default value for YCbCrSubSampling is [2, 2], so it might be allowed not to write it. Reading quickly http://www.remotesensing.org/libtiff/TIFFTechNote2.html does not show any evidence that the tag is required if the subsampling is equal to the default value. But that's just my interpretation...