[ptx] Release: autopano-sift 1.5: bug fixes and exciting newfeatures

[alexandre jenny]

Excellent, good job Sebastian.

BTW : do you have any reason why I cannot email you ? (It always bounce me
back ...)

Alexandre


> -----Message d'origine-----
> De : ptx-bounces at email-lists.org 
> [mailto:ptx-bounces at email-lists.org] De la part de Sebastian Nowozin
> Envoyé : vendredi 6 août 2004 08:42
> À : ptx at email-lists.org
> Objet : [ptx] Release: autopano-sift 1.5: bug fixes and 
> exciting newfeatures
> 
> 
> 
> Hello everybody,
> 
> after a long time travelling and being unable to respond to 
> all the mails, I finally found time to improve upon 
> autopano-sift and fix the bugs Alexandre reported. Thanks for 
> the reports, it really improves the results. Besides various 
> other smaller improvements detailed in the changelog below, I 
> put in three exciting new features, which I hope will improve 
> the results a lot:
> 
>  1. Automatic pre-aligning of images
>     In case the images fullfil some simple criterias (first 
> images lie in a row
>     on the horizon in either strict left-to-right or 
> right-to-left order), all
>     the images can be pre-aligned so the panotools optimizer 
> has a good minima
>     to start from instead of trying rather randomly. Also 
> includes a "bottom
>     estimator", that guesses about where the bottom of an 
> image is based on
>     keypoint density. You can override the use of that by using
>     --bottom-is-left or --bottom-is-right for 90/-90 degree 
> rotated images. The
>     automatic estimation works well for landscape photography.
> 
>  2. Automatic horizon generation
>     Under the same conditions as in 1., automatic generation 
> of horizon lines
>     can be enabled.
> 
>  3. Component enumeration
>     After matching, all connected components are enumerated 
> and shown. This
>     way, you can quickly see which image groups are failing 
> to match and can
>     either increase keypoint density by increasing the 
> downscaleResolution, or
>     by manually fixing the components together.
>     Question: does hugin's wizard check for components or 
> only single images?
> 
> 
> The release is available at the usual location:
> 
> 	http://user.cs.tu-berlin.de/~nowozin/autopano-sift/
> 
> Please test and let me know of your results, but do not 
> expect a reply before September, as I will be travelling 
> again. I promise to check every report I receive in the 
> meantime though.
> 
> 
> The detailed changelog follows:
> 
> autopano-sift 1.5, libsift 1.3
> 2004/08/06
> 
>   * Fix two severe mathematical bugs found by Alexandre Jenny
>     (autopano at kolor dot com). Thanks! One is a wrong 
> factor in a matrix
>     calculation that lead to fewer keypoints being detected. 
> Another is an
>     algorithmic bug that also reduced the number of 
> keypoints. This bug has
>     previously been found by Willi Nagel (lascobar at gmx dot 
> de), but I did
>     not recognized it back then, sorry. Both bugfixes 
> together double the
>     number of keypoints generated.
>   * Fix documentation of generatekeys, where the 
> downscaleResolution option
>     was not explained correctly.
>   * Change behaviour of the downscale resolution in the 
> generatekeys utility.
>     By supplying zero as downscale resolution, the image is 
> taken verbatim,
>     without any scaling.
>   * Fix small bug in autopano GUI: images are no longer added 
> when cancel is
>     hit in the file selection dialog.
>   * Fix a rare bug where a RANSAC model fit was accepted that 
> was not fitted.
>     This occured only when at two or more scales the same 
> point location was
>     selected to fit a model.
>   * Change the Best-Bin-First search cutoff depth from static 130 to
>     logarithmically increasing, depending on the overall 
> keypoints (formula
>     is (ln(keypoints)/ln(1000))*130. This increases accuracy, 
> but introduces a
>     logarithmic factor into the otherwise linear time complexity.
>   * Change the autopano-complete.sh script so that a 
> downscale resolution of
>     800 pixels is used in case none is given. Any given 
> railable on the command
>     line utility (autopano.exe) and has to be enabled through 
> the "--align"
>     option. See the manpage for further information on 
> restrictions on images
>     that can be used with this option. This computation comes 
> at virtually no
>     costs and everybody should try it out :-)
>   + Add the "--bottom-is-left" and "--bottom-is-right" 
> options for use with
>     "--align" option, in case 90/-90 degree tilted images are 
> not properly
>     recognized.
>   + Add experimental horizon generation. This works only in 
> conjunction with
>     the "--align" option and simply puts up to a given number 
> of horizontal
>     control point lines on the images found to be in the first row.
> 
> 
> Thanks for testing,
> Sebastian
> 
> -- 
> nowozin at cs.tu-berlin.de --- http://user.cs.tu-berlin.de/~nowozin/
>