1IM_JPEG2VIPS(3) Library Functions Manual IM_JPEG2VIPS(3)
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6 im_jpeg2vips, im_vips2jpeg, im_vips2bufjpeg, im_vips2mimejpeg - convert
7 JPEG images to and from VIPS format
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10 #include <vips/vips.h>
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12 int im_jpeg2vips( char *filename, IMAGE *out )
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14 int im_jpeg2vips_header( char *filename, IMAGE *out )
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16 int im_vips2jpeg( IMAGE *in, char *filename )
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18 int im_vips2bufjpeg( IMAGE *in, IMAGE *base, char **obuf, int *olen )
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20 int im_vips2mimejpeg( IMAGE *in )
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24 im_jpeg2vips() reads the named jpeg file and writes it to the specified
25 IMAGE. The entire image is read before returning. It will handle 1 and
26 3 band 8-bit images only.
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28 Any embedded ICC profiles are ignored: you always just the the RGB from
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31 im_jpeg2vips_header() reads just the header of the JPEG file, and sets
32 the fields in the VIPS image. You can't read any pixels! This is only
33 useful for printing header information.
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35 im_vips2jpeg() writes the IMAGE to filename in JPEG format. It uses the
36 default settings of the IJG library.
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38 A compression factor may be encoded in the filename: for example,
39 "fred.jpg" will write with the default compression factor (75),
40 "fred.jpg:25" will write with factor 25.
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42 An ICC profile may also be specified. For example,
43 "fred.jpg:25,/home/john/srgb.icc" will embed the profile stored in the
44 file "/home/john/srgb.icc" into the JPEG image. This does not affect
45 the pixels which are written, just the way they are tagged. Very few
46 image readers respect this tag.
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48 im_vips2bufjpeg() returns the compressed image in a memory buffer. The
49 buffer is allocated for you, local to IMAGE descriptor base. The size
50 of the allocated buffer is returned in the olen parameter. You are
51 responsible for freeing the buffer. The buffer is only allocated if the
52 function returns successfully.
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54 im_vips2mimejpeg() writes the image to stdout as a MIME image/jpeg
55 type. It outputs Content-Length and Content-Type fields making the
56 result suitable for a web browser.
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60 im_isjpeg(3).
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64 6 June 1994 IM_JPEG2VIPS(3)