AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

2005.05.27 07:46 "[Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & compress", by Kelvin Zhong
2005.05.28 17:21 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & compress", by Joris Van Damme
2005.05.30 09:58 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & co mpress", by Kelvin Zhong
2005.05.30 13:32 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & compress", by Jean-Yves Le Ridant
2005.05.31 07:24 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & com press", by Kelvin Zhong
2005.06.29 20:21 "[Tiff] copying jpeg tables", by James Carroll

2005.05.31 07:24 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & com press", by Kelvin Zhong

Thanks Jean,

This time I "attach"(or convert) a JFIF-FILE to a JPEG-IN-TIFF FILE I parsed some infomation i need to know,such as ImageWidth,ImageLength,BitsPerSample, SamplesPerPixel...,(this data are contained in the SOF0 MARKER,) and i also figure out the YCBCRSUMPLING value i need to use for a JPEG-IN-TIFF FILE.

but i failed to Get the DPI value of jpeg image file. (xresolution or yresolution ?), i search for a detailed specification of JFIF (JPEG IMAGE file format),but failed.

does anyone have a detailed information about JFIF format (i only have got a specification called:<JPEG File Interchange Format v1.02.>

my question is :how i can a DPI value from a JPEG-DATA stream? where does it reside in?

thanks in advance

yourpattern@126.com
Kelvin Zhong