[ptx] Autopano-sift -> Hugin -> Enblend Workflow

[Ian Sydenham]

Is anyone interested in discussing Autopano-sift ->Hugin -> Enblend workflow 
using W2k?

There seem to be a few people on list list using at least some of this software 
and I'd like to see if the way I use it is similar, or if there is a 
quicker/better way. The description of how I use it is a bit terse, but 
hopefully it contains enough for someone who already uses these programs to know 
what I am trying to explain.
I'm a bit wary of posting to this ptx list as the topic may be a bit
more "user" focused than developer focused, and very W2k biased, but this is 
the best place to post that I know of.

Firstly my set-up

Hardware:
Intel D865PERL motherboard
P4-2.40GHz CPU
512 MB RAM

OS: Windows 2000-sp4

Panorama software:
Pano12.dll: v2.7 Beta3 - Rik Littlefield
Autopano-sift: v1.3 - Sebastian Nowozin
Hugin: hugin snapshot - hugin_2004_03_25-08_41_win32
Enblend: Enblend1.3- with patch by Edouard Gomez as incorporated into the latest
enblend at http://wurm.wh-wurm.uni-ulm.de/~redman/enblend.exe

The way I use these packages right now to create full or partial panoramas is 
like this:

1. Copy the images I want to use for the panorama into my image working folder 
(C:\Program Files\autopano-sift\tmp)
2. Run a batch file I have created
(C:\Program Files\autopano-sift\bin\AutopanoIt.cmd) to create the Hugin Project 
File (normally Hugin.pto). The batch file checks to make sure that I have got 
some files to work with, creates the autopano key files and then calls 
autopano-sift to create the hugin file.
3. Start Hugin and then open the Hugin.pto file.
4. Change the image hfov to my camera's setting (normally 38mm), set the
reference image for position (and exposure), and create vertical line control
points for images (if I can), and add any additional control point pairs where I
think they may be of some use.
5. Optimise for the default setting of "Positions (pairwise optim., starting
from anchor)", then save.
6. Look at the "points" table and see if there are any wild points with large
distances. If there are then review the point pair to see if is correct and
decide to adjust it, remove it, or keep it. If I changed anything then re-do the
optimisation step.
7. Preview the image in the preview window, check that it looks OK, then centre
the image and save the project.
8. Optimise using custom optimisation - for Yaw roll and pitch (yaw fixed for
the reference image).
9. Optimise again adding barrel.
10. Optimise again adding view v.
11. Optimise again adding distortion a and b.
(Sometimes I get better results by swapping steps 10 and 11)

(I separate these optimisation steps because it seems to be a more reliable way
to get a "good" solution without drifting off to a wild set of parameters. After
each step I look at the preview window and the points table to see if anything
has gone wild, and if it has then I revert to the previous step and try to find
what went wrong)

12. Open the Hugin Stitcher Tab and set the pixel width to 1024, image format to 
JPG (90%) and then stitch now!
13. I then open this image (using irfanview) and check that it looks OK. If it
does not then I try lots of things - more control points, less control points...
14. Assuming it looks OK then I set the pixel width to the default (click on
"Calculate Pixel Dimensions") and stitch again using nona and multiple Tiff with
the file name nona.tiff saved into the folder C:\Program Files\autopano-sift\tmp
14a. If the image is a 360 deg panorama then (since I started using the patched 
enblend) I open the created tiff file in GIMP and resize the image by one pixel 
column to remove the blank column of pixels at the right side of the image
15. I delete the 0 byte file nona.tiff (leaving nona.tif for later use) then
start enblend using a batch file I have created
C:\Program Files\autopano-sift\bin\EnblendIt.cmd.
The batch file looks for tiff files in the directory C:\Program 
Files\autopano-sift\tmp and runs enblend to create a JPG file enblended.tif. 
This works not only with multiple layer tiff files, but also with multiple tiff 
files (I have not tried it with a mix of both). It then uses image magic 
"convert.exe" to convert this to a (smaller) PNG file and deletes the enblended 
tiff file.
16. I preview this then do any final "tweaks" using Gimp. If there are any very
bad join problems (I mostly take hand-held shots and sometimes it's not so good)
I use pieces of the images from the the Hugin output tiff file to paste over 
with corrections.

regards,

Ian Sydenham