# Image package

The image package is part of the octave-forge project. See its homepage for the latest release.

## Development

Follows an incomplete list of stuff missing in the image package to be matlab compatible. Bugs are not listed here, search and report them on the bug tracker instead.

### Roadmap

The following are missing targets for the next minor release of the image package (version 2.8.0). Small bug fixes, build fixes, and regressions may still be released before in a patch release (Version 2.6.X).

- add ellipse properties to
`regionprops`

(see bug #44100) (done) - speed up
`regionprops`

for large images with many small objects (probably work around for loop with labeled == labelid) - support passing
`bwconncomp`

output to`regionprops`

(and then fix`bwpropfilt`

to use that instead of a labeled image) - ND support on
`imfilter`

- check if
`normxcorr2`

is Matlab compatible and investigate making use of`fftconvn`

since it's likely to receive large input - investigate implementing the missing deconvolution functions (see patch #8571)
- anything else that is done or submitted before the above are done

### Missing functions

- activecontour
- adapthisteq
- affine2d
- affine3d
- applycform
- axes2pix
- bwconvhull
- bwdistgeodesic
- bwlookup
- bwpack
- bwtraceboundary
- bwulterode
- bwunpack
- chromadapt
- colorangle
- colorcloud
- convmtx2
- corner
- cornermetric
- cpcorr
- cpselect
- cpstruct2pairs
- dct2
- dctmtx
- deconvblind
- deconvlucy
- deconvreg
- deconvwnr
- decorrstretch
- demosaic
- dicomanon
- dicomdisp
- dicomuid
- dpxinfo
- dpxread
- fan2para
- fanbeam
- fliptform
- freqz2
- fsamp2
- ftrans2
- fwind1
- fwind2
- gabor
- getimage
- getimagemodel
- getline
- getpts
- getrect
- gradientweight
- grayconnected
- graycoprops
- graydiffweight
- hdrread
- hdrwrite
- houghlines -- (see hough_line)
- houghpeaks
- iccfind
- iccread
- iccroot
- iccwrite
- idct2
- ifanbeam
- illumgray
- illumpca
- illumwhite
- im2java2d
- ImageAdapter
- imageinfo
- imapplymatrix
- imapprox
- imbinarize
- imboxfilt
- imboxfilt3
- imcolormaptool
- imcontour
- imcontrast
- imdisplayrange
- imdistline
- imellipse
- imfreehand
- imfuse
- imgaborfilt
- imgaussfilt
- imgaussfilt3
- imgca
- imgcf
- imguidedfilter
- imhandles
- imhistmatch
- imline
- immagbox
- immovie
- imoverview
- imoverviewpanel
- impixelinfo
- impixelinfoval
- impixelregion
- impixelregionpanel
- implay
- impoint
- impoly
- improfile
- imrect
- imref2d
- imref3d
- imregconfig
- imregcorr
- imregdemons
- imregister
- imregtform
- imroi
- imscrollpanel
- imsegfmm
- imseggeodesic
- imshowpair
- imtool
- imwarp
- integralBoxFilter
- integralBoxFilter3
- integralImage
- integralImage3
- interfileinfo
- interfileread
- iptaddcallback
- iptcheckhandle
- iptgetapi
- iptGetPointerBehavior
- iptgetpref
- ipticondir
- iptPointerManager
- iptprefs
- iptremovecallback
- iptSetPointerBehavior
- iptsetpref
- iptwindowalign
- isicc
- isrset
- lin2rgb
- makecform
- makeConstrainToRectFcn
- makehdr
- makeresampler
- multithresh
- nitfinfo
- nitfread
- openrset
- otsuthresh
- para2fan
- projective2d
- regionfill
- rgb2lin
- roifill
- roifilt2
- roipoly
- rsetwrite
- ssim
- tformarray
- tonemap
- truesize
- visboundaries
- warp
- whitepoint
- xyz2double
- xyz2uint16

### Different functions

- with version 2014a, Matlab introduced a new function imtranslate. This function was part of Octave's package since 2002 but Matlab version is completely different. It needs to be rewritten for Matlab compatibility.

### Missing options

- @strel
- missing SE decomposition for the diamond shape
- approximation argument for the ball and disk shapes are not implemented
- the translate method is not yet implemented

- blockproc
- The name-value input arguments have not yet been implemented.

- colfilt
- the option to split the image in smaller blocks before performing the im2col and filtering is ignored. Since that option only allows to use less memory and has no effect on the output is only important for sliding filtering with big blocks size.

- impixel
- interactive selection of points (less than 2 input arguments) is not yet implemented. Ability to create such UIs needs to be implemented in Octave core first.

- imcrop
- messing around with alternative coordinate systems (XData and YData) are not yet implemented.

- imwrap
- no supports for SmoothEdges option

- hough
- no RhoResolution option

### Contributing

- It'd help to group the missing functions above, as per [1] (similar to what was done in the signal package wiki page); please keep the original alphabetical list intact.

### Open Bugs

bug | bug title | status |
---|---|---|

#38085 | image package: fails to build with --enable-64 (entropyfilt) | Confirmed |

#38087 | image package: graycomatrix incompatibilities with matlab | None |

#38345 | image package: __spatial_filtering__() always returns class double | Confirmed |

#41674 | image package: temporary arrays in imresize are doubles | None |

#43218 | image package: imshear causes more signal spread than expected and inconsistent vertical offset | None |

#44396 | image package: bwmorph shrink does not preserve Euler number | Confirmed |

#44799 | image package: imrotate chrashes when using 'spline' as interpolation method | Confirmed |

#44831 | image package: imrotate - different dimensions of output matrix | Confirmed |

#45088 | image package: rangefilt requires domain and image to have equal number of dimensions | Patch Reviewed |

#46745 | image package: imresize default method (bicubic) Matlab incompatible for the border pixels | None |

#48529 | image package: compilation warnings under Mac OSX | None |

#50071 | OF image: bwfill(...,4) in Octave behaves like bwfill(...,8) in MATLAB and vice versa | None |

#50151 | image package: normxcorr2 is not compatible with Matlab | None |

#50188 | image package: poly2mask does incompatible rounding | None |

#50257 | image package: imtranslate is not Matlab compatible | Confirmed |

#50341 | Missing Function imrect in image package | None |

#50429 | image package: xyz2lab changed slightly in Matlab (and other color conversion functions) | None |

#50656 | image package: bwerode does not return right size when there's more dimensions on conn | None |

#50708 | image package: add demosaic.m | Patch Submitted |

#50732 | Image package: infinite error loop when assigning a strel (class) object to a vector | Confirmed |

#50783 | image package: imlincomb is not compatible with Matlab | Patch submitted |

#50874 | bwdist call causes application crash | Confirmed |

#51420 | [octave forge] (image) imrotate is less tolerant to missing argument than Matlab | None |

#51719 | [octave forge] (image) watershed unit test failure | None |

#51769 | [octave forge] (image) imresize bilinear interpolation inaccurate | Patch Submitted |

#51884 | [octave forge] (image) bwmorph(blackNwhiteMatrix, "thicken", 1) returns negated result (+ strange behavior at border) | None |

#51979 | [octave forge] (image) Failing unit test for impyramid | None |

#51980 | [octave forge] (image) Failing unit test for edge | None |

#51981 | [octave forge] (image) Failing unit test for otf2psf | None |

#51982 | [octave forge] (image) Failing unit test for nlfilter | None |

#52006 | [octave forge] (image) 'makecform' feature request | Confirmed |

#52119 | [octave forge] (image) Add 'reflect' padding option to imfilter | None |

#52715 | [octave forge] (image) Add full data range option to ycbcrfunc conversions | None |

#52933 | [octave-forge] (image) regionprops Perimeter returns Matlab incompatible results | Patch Submitted |

#52959 | [octave-forge] (image) histeq is not compatible with Matlab | None |

#53090 | [octave-forge] (image) imhist fails in dev version due to changes in colorbar | None |

#53309 | [octave forge] (image) imrotate of +/-90 degrees results in black image when 'crop' and RGB image as input | In Progress |

### Patches

- #8059: [new function for image package] ranktf.m
- #8060: [image package new function] whitepoint.m
- #8722: implement impixelinfo and impixelinfoval
- #8813: image package: Extended image I/O for Analyze 7.5 format to handle big-endian images
- #8866: image package: add metainfo.xml file for Gnome Software
- #8571: image package: three deconvolution routines (Wiener, RL, RLTV)
- #8824: added affine2d class
- #9235: image package: improve filtering functions (stdfilt, entropyfilt) and add tests (also medfilt2, ordfilt2, rangefilt)
- #9244: image package: regionprops.m - new properties ConvexHull, ConvexImage, ConvexArea, Solidity
- #9354: image package: new function wiener2.m
- #9360: image package: new function otsuthresh.m
- #9365: image package: new function deconvwnr.m
- #9407: image package: new function houghpeaks.m
- #9412: image package: new function houghlines.m
- #9509: Image package: simple implementation of roipoly function

## Image Processing Functions

This is a list of Image Processing functions by topic including: missing functions, related bugs and patches, and some alternatives.

Note:

### Basic Read and Write Image Files

Function | Octave Package Version | Related Bugs and Patches | Alternatives | Notes |
---|---|---|---|---|

imfinfo | function is in Octave core | |||

imread | function is in Octave core | cv.imread from mexopencv |
in case of color image, the color order of Octave is RGB/RGBA while OpenCV color order is BGR/BGRA | |

imwrite | function is in Octave core | cv.imwrite from mexopencv |
in case of color image, the color order of Octave is RGB/RGBA while OpenCV color order is BGR/BGRA |

**Missing:** *dicomanon, dicomdisp, dicomuid, dpxinfo, dpxread, interfileinfo, interfileread, nitfinfo, nitfread*

### High Dynamic Range Images - *Not implemented*

### Large Image Files - *Not implemented*

### Type Conversion

Function | Octave Package Version | Related Bugs and Patches | Alternatives | Notes |
---|---|---|---|---|

adaptthresh | - | cv.adaptiveThreshold from mexopencv | ||

demosaic | - | #50708 | cv.demosaicing from mexopencv | |

gray2ind | function is in Octave core | |||

grayslice | < 1.0.0 | |||

graythresh | 1.0.0 | Octave version has more methods | ||

im2double | 1.0.0 | |||

im2int16 | 2.0.0 | |||

im2java2d | - | |||

im2single | 2.0.0 | |||

im2uint16 | 1.0.0 | |||

im2uint8 | 1.0.0 | |||

imbinarize | - | imbinarize (I) is equivalent to im2bw(I, graythresh(I)),
another option is cv.threshold from mexopencv |
||

imcast | 2.4.0 | Octave Only | ||

imquantize | 2.6.0 | |||

ind2gray | function is in Octave core | |||

ind2rgb | function is in Octave core | |||

label2rgb | 1.0.0 | |||

mat2gray | < 1.0.0 | |||

multithresh | - | |||

otsuthresh | - | #9360 | graythresh | otsuthresh(hist) is equivalent to graythresh (hist) |

rgb2gray | < 1.0.0 | |||

rgb2ind | function is in Octave core |

**Missing:** *demosaic*

### Color

Function | Octave Package Version | Related Bugs and Patches | Alternatives | Notes |
---|---|---|---|---|

lab2double | - | |||

lab2rgb | - | |||

lab2uint16 | - | |||

lab2uint8 | - | |||

lab2xyz | - | |||

ntsc2rgb | function is in Octave core | |||

rgb2lab | - | |||

rgb2ntsc | function is in Octave core | |||

rgb2xyz | - | |||

rgb2ycbcr | - | |||

xyz2lab | - | |||

xyz2rgb | - | |||

ycbcr2rgb | - |

**Missing:** *applycform, chromadapt, colorangle, colorcloud, iccfind, iccread, iccroot, iccwrite, illumgray, illumpca, illumwhite, imapprox, isicc, lin2rgb, makecform, rgb2lin, whitepoint, xyz2double, xyz2uint16*

### Synthetic Images

Function | Octave Package Version | Related Bugs and Patches | Alternatives | Notes |
---|---|---|---|---|

checkerboard | - | |||

imnoise | - | |||

phantom | - |

### Basic Display

Function | Octave Package Version | Related Bugs and Patches | Alternatives | Notes |
---|---|---|---|---|

imshow | function is in Octave core | |||

montage | - |

**Missing:** *imfuse, immovie, implay, imshowpair, iptgetpref, iptprefs, iptsetpref, warp*

### Image Filtering

Function | Octave Package Version | Related Bugs and Patches | Alternatives | Notes |
---|---|---|---|---|

bwareafilt | 2.4.0 | |||

bwpropfilt | 2.4.0 | |||

convmtx2 | - | |||

entropyfilt | 1.0.9 | #9235 | ||

fibermetric | - | |||

freqz2 | - | |||

fsamp2 | - | |||

fspecial | 1.0.0 | |||

ftrans2 | - | |||

fwind1 | - | |||

fwind2 | - | |||

gabor | - | |||

imboxfilt | - | |||

imboxfilt3 | - | |||

imfilter | 1.0.5 | |||

imgaborfilt | - | |||

imgaussfilt | - | |||

imgaussfilt3 | - | |||

imguidedfilter | - | |||

imsmooth | 1.0.5 | Octave only | ||

integralBoxFilter | - | |||

integralBoxFilter3 | - | |||

integralImage | - | cv.integral from mexopencv | ||

integralImage3 | - | |||

medfilt2 | < 1.0.0 | #9235 | ||

medfilt3 | - | |||

nlfilter | < 1.0.0 | |||

normxcorr2 | 2.0.0 | #50151 | ||

ordfilt2 | 1.0.9 | #9235 | ||

padarray | < 1.0.0 | |||

rangefilt | 1.0.9 | #45088 #9235 | ||

stdfilt | 1.0.9 | #9235 | ||

wiener2 | dev |

### Image Arithmetic

Function | Octave Package Version | Related Bugs and Patches | Alternatives | Notes |
---|---|---|---|---|

imabsdiff | 2.0.0 | |||

imadd | 2.0.0 | |||

imapplymatrix | - | |||

imcomplement | 1.0.6 | |||

imdivide | 2.0.0 | |||

imlincomb | 2.0.0 | #50783 | ||

immultiply | 2.0.0 | |||

imsubtract | 2.0.0 |

### Morphological Operations

Function | Octave Package Version | Related Bugs and Patches | Alternatives | Notes |
---|---|---|---|---|

applylut | < 1.0.0 | |||

bwareaopen | 2.2.0 | |||

bwhitmiss | < 1.0.0 | |||

bwlookup | -- | |||

bwmorph | < 1.0.0 | #51884 | ||

bwulterode | -- | |||

conndef | < 1.0.0 | |||

imbothat | 2.0.0 | |||

imclearborder | 2.4.0 | |||

imclose | < 1.0.0 | |||

imdilate | < 1.0.0 | |||

imerode | < 1.0.0 | |||

imextendedmax | dev | #9488 | ||

imextendedmin | dev | #9488 | ||

imfill | 2.6.0 | |||

imhmax | dev | #9488 | ||

imhmin | dev | #9488 | ||

imimposemin | dev | #9488 | ||

imopen | < 1.0.0 | |||

imreconstruct | 2.4.0 | |||

imregionalmax | 2.4.0 | |||

imregionalmin | 2.4.0 | |||

imtophat | < 1.0.0 | |||

iptcheckconn | 2.0.0 | |||

offsetstrel | -- | |||

strel | 2.2.0 | #50732 | ||

watershed | 2.6.0 |