libvips/TODO

- we have this is many places:

	if( vips_image_copy_fieldsv( conversion->output, 
		insert->main, insert->sub, NULL ) )
		return( -1 );
        vips_demand_hint( conversion->output, 
		VIPS_DEMAND_STYLE_THINSTRIP, insert->main, insert->sub, NULL );

  why not combine these into a single API call?

  use array version in several places



- do clip etc. in new style, good to get everything that VipsAdd uses in
  the new stack

  embed needs flip* *join extract_area replicate insert

  *join needs insert too

  insert* needs clip, lintra_vec





- change the way we wrap vips7 operations

  make im_max() appear in vips8 as "im_max" (we wrap as "max" right now), this
  will help compatibility when we redo as a class and create "max"

  make vips.c try the vip8 APIs for an operation before falling back to vips7

  ... actually, leave it alone, it can never work well, no point encouraging
  its use




- we have some serious exif problems

  we attach exif as both the original exif data and as a set of broken-out
  tags, such as 'exif-Orientation' ... the tags are attached as strings

  when we write a jpg file, we parse the original exif block, update the
  resolution and Orientation tags from metadata, and add to the output file

  we need a way to update the exif block with all 'exif-' tags, but this is
  hard because a tag is 

	tag
  	format (eg. short, rational, string)
	components (for short, for example, you can have an array of 12)
	data (byte buffer)
	size (sizeof byte buffer)

  many tags have extra meanings, for example Orientation means that the format
  must be short and the data must be 1, 2, 3, 4, 5, 6, 7 or 8 for the 8
  possible rotates and flips ... libexif does not expose any way to convert
  strings to enum values safely, what do we do with "Bottom-right"

  how do we expose this to bindings in a sane way, how do we accurately
  convert the updated tag values back into correct exif when we reattach

  additionally, exif tags can be in one of several ifd blocks, do we need to
  add the tag to the correct block? how do we save that information?

  oo! we have the original, of course

  to reattach, get the entry from the original exif block, get the updated
  tag, coerce the updated value back to the orginal format

  save exif entries to tags as something like:

	exif-Orientation: 1 (Top-left, Short, 1 component, 2 bytes)

  so we can restore the value from the "1" without needding to look up i18n
  strings




- vips_object_set_argument_from_string() needs more arg types

  must be some way to make this more automatic




- add nifti support

	http://niftilib.sourceforge.net/







- add vips_init_argv() which processes argc/argv for you? handy for tiny
  progs, perhaps




- generate the code for vips_add() etc. automatically? it might be 
  nice to have them all in one place at least




- all the old dispatch wrappers could move to deprecated




- support planar tiff




- vips operation print could show operation flags as well, cf. "vips
  im_subtract"

  haha, we don't have any flags like that on operation ... NOCACHE looks
  useful, should we add that? any others?

  maybe wait until we have to




- revisit orc conv

  use an 8.8 accumulator ... build the scale into the 8.8 coeffs ... no div at
  the end, just a shift

  need 8 x 8.8 -> 8.8 for each coeff though






- also VipsFormat ... could this replace vips_image_new_from_string()? or
  could we call this from vips_image_new_from_string()? 

  at the moment, VipsFormat subclasses never get made, we just use the classes
  ... we'd need to start making real vipsformat objects for this to work

  how would this work?

  at the moment we have

  	image = vips_image_new_from_file( filename );

	build a VipsImage with filename "r"

  we also have the new CLI thing

  	obj = vips_object_new_from_string( class, str );

	calls class->new_from_string( first-component(str) ), then sets
	optional args from rest-of-str(str), then does _build()

	image-class->new_from_string() just make a vipsimage "r" str

	the _build() uses VipsFormat() to load via im_tiff2vips() or whatever

  so ... we could change vips_image_new_from_file() to be

  	VIPS_IMAGE( vips_object_new_from_string( VipsImageClass, str ) )

  we could also make VipsImage::new_from_string() make a real VipsFormat
  object, then load options could be set from the str

  how does save work? we call image-class->output_to_arg(obj, str), which in
  turn calls vips_image_write(), which in turn uses VipsFormat


  



- make a vips8 binding for Python as well

  use ctypes and not swig so we get an easy Win version

  wrap new API for C++






- Magick: 

	- do we bundle "convert" in the OS X / win32 builds? if we don't we
	  should




- need vips_image_invalidate_area()






- add matlab write

- need a way to make the vips.1 etc. man pages

  gtk has things like docs/reference/gtk/gtk-update-icon-cache.xml and man
  pages are made from that with xslt

- get rid of a lot of the command-line programs, who wants to write a man page
  for batch_image_convert etc yuk

- can we make man pages for the API as well? probably not from googling a bit



- use g_mmap() or whatever it's called ... or perhaps they don't have all
  these options




- use |_O_TEMPORARY to open()'s mode on Windows for tmpfiles to increase the
  chances we actually delete

  see http://www.mail-archive.com/bug-gnulib@gnu.org/msg05730.html





- lab [100,0,0] -> srgb [255, 255, 254]? how odd









- im_conv()/im_morph() could have more than 10 programs? try 20 and see if we
  still have a speedup

  make a base class for vector area operations with a matrix with three vfuncs
  for init / generate code for one element / end and a gslist of programs, use
  that as the base for morph and conv

  wait for vipsobject for this




- perspective transform with a matrix ... base it on the Lenz transformer, but
  partial





- maybe im_draw_smudge() is too slow :-( also, we had a sanity failure with
  it, argh

  make a region, prepare to that, copy back over the image?




- use D65 in cmsCreateLab4Profile() ? not sure

- im_divide() can /0 for complex 

- unlink temps earlier on *nix systems

  the file is created by setupout, which is called just before generate or
  writeline, so perhaps unlink on evalstart?

  no, on a rewind we need to be able to close and reopen, argh




- test

		python setup.py build_ext
		python setup.py build
		python setup.py install


>>> from vipsCC import *
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.6/dist-packages/vipsCC/VImage.py", line 25, in
<module>
    vimagemodule = swig_import_helper()
  File "/usr/local/lib/python2.6/dist-packages/vipsCC/VImage.py", line 21, in
swig_import_helper
    _mod = imp.load_module('vimagemodule', fp, pathname, description)
ImportError: /usr/local/lib/python2.6/dist-packages/vipsCC/vimagemodule.so:
swig_import_helper
    _mod = imp.load_module('vimagemodule', fp, pathname, description)
ImportError: /usr/local/lib/python2.6/dist-packages/vipsCC/vimagemodule.so:
undefined symbol: _ZTIN4vips5VMaskE

ie. vimagemodule.so can't find libvipsCC.so I guess? or perhaps the compiler
is being given a differnt mangling flag

we're building with:

gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall
-Wstrict-prototypes -fPIC -DDEBUG_FATAL=1 -DDEBUG_LEAK=1
-I/usr/lib/glib-2.0/include -I/usr/include/pango-1.0 -I/usr/include/libxml2
-I/usr/include/libpng12 -I/usr/include/libexif -I/usr/include/glib-2.0
-I/usr/include/freetype2 -I/usr/include/OpenEXR -I/usr/include/ImageMagick
-I../../libvips/include -I../../libvipsCC/include -I/usr/include/python2.6 -c
vimagemodule.cpp -o build/temp.linux-x86_64-2.6/vimagemodule.o -pthread
-fopenmp -pthread -Wl,--export-dynamic -pthread -pthread -pthread

g++ -pthread -shared -Wl,-O1 -Wl,-Bsymbolic-functions
build/temp.linux-x86_64-2.6/vimagemodule.o -Wl,-R/home/john/vips/lib
-lMagickWand -lMagickCore -lpng12 -ltiff -lz -ljpeg -lgthread-2.0 -lrt
-lglib-2.0 -lgmodule-2.0 -lxml2 -lgobject-2.0 -lgthread-2.0 -lrt -lglib-2.0
-lpangoft2-1.0 -lpango-1.0 -lfreetype -lfontconfig -lgobject-2.0 -lgmodule-2.0
-lgthread-2.0 -lrt -lglib-2.0 -lfftw3 -lm -llcms -lIlmImf -lz -lImath -lHalf
-lIex -lIlmThread -lmatio -lz -lexif -lm -lstdc++ -lm -o
build/lib.linux-x86_64-2.6/vipsCC/vimagemodule.so -pthread -fopenmp -pthread
-Wl,--export-dynamic -pthread -pthread -pthread

how does this compare to the working build? swig/vipsCC does

g++ -DHAVE_CONFIG_H -I. -I../.. -I../../libvips/include -I../../libvipsCC/include -DDEBUG_FATAL -DDEBUG_LEAK -pthread -fopenmp -I/usr/lib/glib-2.0/include -I/usr/include/pango-1.0 -I/usr/include/libxml2 -I/usr/include/libpng12 -I/usr/include/libexif -I/usr/include/glib-2.0 -I/usr/include/freetype2 -I/usr/include/OpenEXR -I/usr/include/ImageMagick -I/usr/include/python2.6 -g -Wall -MT vimagemodule.lo -MD -MP -MF .deps/vimagemodule.Tpo -c vimagemodule.cxx -o vimagemodule.o >/dev/null 2>&1

g++ -shared -nostdlib /usr/lib/gcc/x86_64-linux-gnu/4.4.3/../../../../lib/crti.o /usr/lib/gcc/x86_64-linux-gnu/4.4.3/crtbeginS.o  .libs/vimagemodule.o   -Wl,-rpath -Wl,/home/john/SVN/vips/vips7/trunk/libvipsCC/.libs -Wl,-rpath -Wl,/home/john/SVN/vips/vips7/trunk/libvips/.libs -Wl,-rpath -Wl,/home/john/vips/lib ../../libvipsCC/.libs/libvipsCC.so ../../libvips/.libs/libvips.so /usr/lib/libMagickWand.so /usr/lib/libMagickCore.so -lpng12 /usr/lib/libtiff.so /usr/lib/libjpeg.so /usr/lib/libxml2.so /usr/lib/libpangoft2-1.0.so /usr/lib/libpango-1.0.so /usr/lib/libfreetype.so -lfontconfig /usr/lib/libgobject-2.0.so /usr/lib/libgmodule-2.0.so /usr/lib/libgthread-2.0.so -lrt /usr/lib/libglib-2.0.so /usr/lib/libfftw3.so /usr/lib/liblcms.so /usr/lib/libIlmImf.so -lImath -lHalf -lIex -lIlmThread /usr/lib/libmatio.so -lz /usr/lib/libexif.so -L/usr/lib/gcc/x86_64-linux-gnu/4.4.3 -L/usr/lib/gcc/x86_64-linux-gnu/4.4.3/../../../../lib -L/lib/../lib -L/usr/lib/../lib -L/usr/lib/gcc/x86_64-linux-gnu/4.4.3/../../.. -L/usr/lib/x86_64-linux-gnu -lstdc++ -lm -lc -lgcc_s /usr/lib/gcc/x86_64-linux-gnu/4.4.3/crtendS.o /usr/lib/gcc/x86_64-linux-gnu/4.4.3/../../../../lib/crtn.o  -pthread -Wl,--export-dynamic -pthread -pthread -pthread   -pthread -Wl,-soname -Wl,vimagemodule.so -o .libs/vimagemodule.so





- convert_saveable for other writers: tiff, ppm, csv, rad etc.



- expose more of the tone funcs in nip2

- quite a few hist operations have no GUI ... lhisteq, for example? or
  histspec?




- rename header, edvips as vipsheader, vipsedit

  maybe have back compat links?

- should im_rwcheck() copy to disc?

  maybe im_rwcheck_disc() copies to im->filename and maps that

  rather awkward to do atm with the way check.c is structured

- what does G_UNLIKELY() do? can we use it?

- rename vipsCC in SWIG as pyvips?

- look into G_GNUC_DEPRECATED for back compat in vips8

- use

	http://library.gnome.org/devel/glib/stable/glib-Byte-Order-Macros.html

  for swapping ... they are asm macros so we should see a speedup

- can we use conv_sep to speed up the memuse benchmarks?

- check mosaic1, global_balance, similarity etc. use of im__affine
  
  how can we move them to im_affinei ?

- doc strings would be nice, read the SWIG notes on this

- bilateral filtering, see:

	http://en.wikipedia.org/wiki/Bilateral_filter
	http://www.shellandslate.com/fastmedian.html
	http://people.csail.mit.edu/sparis/bf_course/

  also a mail from Martin Breidt has links to several fast free C
  implementations

- need a section for vipsobject in the tutorial

  also a manpage?

  not really stable yet :( don't document

- we shouldn't need to call im_invalidate() in gtkdisp4 :( how can we fix
  this?

- we should wrap the format API, also im_render*(), see gtkdisp.cc for sample
  code

- need an im_init_world() for C++ which does cmd-line args too, so C++ progs
  can get --vips-progress and stuff automatically

- unsharp should work on GREY16? should be easy to add GREY16->LABS

  no, labs is signed short, ranges are all differrent, and the scaling will be
  wrong anyway

  correct: import with ICC to labs, then process, then export to RGB, take
  green?

  yuk, can we add a 16bit path to vips's lab <--> rgb converter?

  use TIFF RGB16 as the 16bit RGB target

  im_XYZ2disp() would be easy to 16bit ... just need the 1,500 element table
  table->t_Yr2r[i] expanded
  
  im_disp2XYZ() uses im_col_rgb2XYZ() in a loop ... again, need
  the 1,500 element table table->t_r2Yr[i] expanded

  usually these three tables (t_r2Yr, t_g2Yg, t_b2Yb) will be identical, can
  we common them up? same for t_Yr2r etc.

  how big should the table be for 16 bits? 256 times larger? too big!

  we really just need a LUT for pow() with the right exponent, eg. 2.4 for
  sRGBs, and one for 1/2.4 ... see what calcul_tables does:

  	table->t_r2Yr[i] = yo + a * pow( i * table->ristep / f + c, ga );

  see



  

- test maxpos_avg, quite a few changes

- HAVE_HYPOT could define a hypot() macro?

- im_exr2vips can now use c++ api

  see TODO notes in openexr read (though they all need more openexr C API)

  consider openexr write

- python startup fails with plugins in vipslib:

	Fatal Python error: can't initialise module vips
	plugin: unable to open plugin "/home/john/vips/lib/resample.plg"
	plugin: /home/john/vips/lib/resample.plg: undefined symbol: im_start_one

  do we need to build plugins with -rpath etc. and more libs?

  or do we need to make sure our python modules export all their im_ symbols?

  check:

  	http://www.swig.org/Doc1.3/SWIGDocumentation.html#Python_nn8
	http://docs.python.org/dist/dist.html
	result = vips_call ("name", args)

  then call that from VImage_method

- do we really need VImage_method? Can't we write

	__getattr__ (self, name) = lambda (obj_to_call, arguments):

  or something like that?

- TIFF load/save should use meta system for unknown tags

- balance should use new meta stuff

- magick2vips should spot ICC profiles and attach them as meta

- also png2vips?

- magick should set some header field for n_frames and frame_height? see also
  analyze

- im_csv2vips() could use "-" for filename to mean stdin

  but then we'd have to read to a malloced buffer of some sort rather than an
  image, since we might need to grow it during the read, since we couldn't
  then seek

- add erode/dilate 3x3 special case using a 512-bit LUT

  ... nope, actually slower :-( we end up doing an inner loop like

  	for( i = 0; i < 9; i++ )
		bits |= (p[o[i]] != 0) << i;

  which is horrible. Maybe if we had a one band true 1 bit image it'd be
  quicker since we could get bits out in parallel and wouldn't have to worry
  about converting non-zero to 1

  could have a Coding type for bitpack? eg. relational produces a bitpack
  image by default, boolean & morph can work on bitpack etc

  maybe something for vips8 ... we could have a flag on operations for the
  coding types they can accept, and if they are passed other type, they are
  automatically converted

- non-linear sharpen: replace each pixel by the lightest or darkest neighbour
  depending on which is closer in value

- can wrap other inplace funcs which use ink now we have vector_to_ink() in
  inplace_dispatch.c

  see also comments in nip2 TODO ... we could auto-wrap in vips_call.c

  cleaner!