Friday 11 December 2020

4D in archaeology: 3D documentation VS 3D reconstruction

 Hi everybody,

On 23 April 2020 I was asked by my friend Piergiovanna Grossi to give a lesson about 3D and archaeology at the University of Verona. Unfortunately I cannot share here this lesson (at least not yet), due to some restrictions. Nevertheless I would like to write a fast post about one of the topics that seem to have surprised the students: the difference, in archaeology, between 3D documentation and 3D reconstruction.

To keep it simple (KISS principle) we have to consider that we can define our reality (at least in a simple way) in 4D, through three spatial dimensions (x,y,z) and a temporal dimension (t). For this reason, when we work on an archaeological project (excavation, survey, etc...) and we want to document something, we have to pay attention that we are not simply registering the data in 3D, but we are doing a digital copy of the object of our investigation, during a specific time lapse, so that we are recording his physical aspect (morphology) as it is at the moment in which we are working on it. In other words, we are recording a 3D of the object as we see it now (but it would be more correct to say that we are recording it in 4D: x,y,z and t). This is what we call archaeological documentation, but we have to keep in mind that the object as we see it can be very different from the shape it had in the past (like the ruins of a castle are different from the castle itself). Moreover we have to consider that a single object may have had various shapes in the past (a castle could be the result of various architectural stages). This is lead us to the main difference between an the archaeological documentation (which record the object as we see it when we study it) and the archaeological reconstruction (which tries to rebuild the original shape of the object in the past).

This difference is important also because, in Digital Archaeology, 3D documentations  and 3D reconstructions are performed with different kind of software. In the first case we can use SfM-MVS techniques with FLOSS like MeshRoom, OpenMVG, etc..., while in the second we use 3D suite like Blender, even if, recently, Cicero Moraes wrote an add-on able to join this two aspects into a single application: OrtgogOnBlender.

Of course, working in Arc-team together with Cicero Moraes, it is obvious for me to mention him for this topic, but this is due not only to his effort in developing OrtogOnBlender, but also because, in order to explain the students this fundamental difference between archaeological documentation and reconstruction, I found out that the best way was to  show the some example of our past projects related with Forensic Facial Reconstruction (FFR). In fact I started showing some example regarding the medieval of Torre dei Sicconi and the roman site of Villa di Valdonega, like the image below...

 

The Roman site of Villa di Valdonega: 3D documentation (up) and 3D reconstruction (down)

... but suddenly everything was more clear when I showed an example of FFR, like this one:

 

The FFR of St. Valentine of Monselice: on the left side the reconstructive model, on the right side the documentation of the skull

Indeed, during an archaeological FFR project, it is pretty simple to understand that the 3D of the skull represent a 3D documentation, while the 3D of the face is a 3D reconstruction.

I hope this post was useful, Have a nice day!



Tuesday 4 August 2020

S. Catherine of Genua FFR: technical report published

Hello everybody,
this summer we are working very hard on some important tasks (an archaeological excavation on the UNESCO site of S. Maria in Valle in Cividale del Firuli and a cultural project with 3D scanning for the National Archaeological Museum MaRTA of Taranto), so I have very few time to write post on ATOR. BTW I do not want to give up, since I think ATOR has been (still is?) a good resource for Free and Open Archaeology on the web. For this reason I will try to keep it up to date with short post, as long as I can.
This post regards the  publication of the technical report of an old (2019) project of ours: the archaeological Forensic Facial Reconstruction of S. Catherine of Genua. I already wrote about this project, which, in short, presented some interesting aspects: the use of OrtogOnBlender for 3D scanning, some reverse engineeing techniques and the free publication of the technical report.
In this post I want to underline this last point. In fact, the free disclosure of this document, with open licenses and in a digital form, reached a wider public (not only among researchers, but also among normal people), so that the Museo dei Cappuccini di Genova decided to print a small  brochure, basing on the technical report, enriched with some contributions of other authors. I think this a good example of free disclosure of scientific and cultural data through the digital publication of the so-called gray literature (technical reports, archaeological documentations and so on) which is widely produced by professionals who work in the field of Cultural Heritage, but it is very rarely disclose.
I will try to translate in English this document as soon as I can. Here below you can see the printed version.

The printed version of the technical report about S. Catherine's FFR project.


Have a nice day!

Saturday 11 April 2020

Single View Reconstruction from profile portraits

Hello everybody,
this fast post is to answer a question my friend and colleague Emanuel Demetrescu asked me. He wanted to know if the software developed by A. Jackson and his equip is working also with profile portraits.
It took me longer than I thought to answer, since it is true that the software has more difficulties in performing this kind of reconstructions and, for a while, my opinion was that it simply did not work. Finally, testing the software with random profile portraits from internet, I tried a picture of a famous actress (Jennifer Lawrence; I hope she does not mind about it, but I am also pretty sure she will never read this post :)).  This portrait was the only photo that worked since that moment and you can see the result here below.

3D reconstruction from a profile photo (Jennifer Lawrence)

Despite some minimal errors in the reconstruction (you can see them in black in the 3D model), the software finally worked, at least with a picture. Now it was the time to test it with some paints. Again I did many test that ended with no result, but than I started to analyse the photo of Jennifer Lawrence to understand why that picture, among many others, was the only one that worked.
My opinion was that, for the software, it is difficult to recognise the face within a profile portrait, probably due to the fact that it has some parameters to check and probably it is looking for two eyes (and does not expect to find just one). So I figured out that the probability to succeed would be higher if the portrait would have some characteristics: profiles with features that makes an area of the face more recognizable; profiles which are not perfectly straight, so that, for instance, it is possible to glimpse the second eye; images with a background very different from the portrait (like in the picture of Jennifer Lawrence, in which the pale face is very visible against a dark background). 
It took me a while to find profile portraits with the two first features in art history, but finally I found them. For the first test I used the face of an angel, painted by Giotto in the Dormitio Virginis. In this paint the angel is blowing on an incense burner, so that his left cheek is very recognizable. In fact the software gave me a result, which you can see here below.

3D profile reconstruction from the Dormition Virginis (Giotto)
For the second test I used a Botticelli's paint and, more precisely, the Portrait of a Young Woman. In this case the profile is not perfectly straight, so I thought there were good chances to succeed. Also in this case the software worked well, giving me the result you can see here below.

3D profile reconstruction from a paint of Sandro Botticelli
After these two positive results with ancient paints, I wanted to do one more test with a picture and especially with one in which the background was very different form the face, so I looked up form other images and I checked directly for photographic portraits. Finally I found a picture of Natalie Portman by Dan Winters. Also in this case the software worked well and here below is the result.

3D reconstruction from a profile portrait of Natalie Portman
In conclusion, after all these test, my opinion is that it is still possible to automatically reconstruct faces from profiles, using the "Large Pose 3D Face Reconstruction from a Single Image via Direct Volumetric CNN Regression" methodology (and software) proposed by Jackman and colleagues, but the images have to be accurately selected and the success rate is very much lower than working with frontal or three-quarter portraits.
I hope that this post will be useful. Have a nice day!

Friday 10 April 2020

Faces 3D Single View Reconstruction

Hello everybody,
as you probably know, if you are a regular reader of ATOR, we worked a lot, in the past, on the topic of human faces, getting involved in aFFR projects and organizing exhibitions. 
Archaeological Foresnic Facial Reconstructions (aFFR) was the technique we used most, working with the protocol we developed through the years, thanks to our specialist Cicero Moraes. For instance, we used this methodology for St. Anthony of Padua (CARRARA et al. 2014), St. Catherine of Genua (BEZZI et al. 2019), for the father of pathological anathomy Giovanni Battista Morgagni (ZANATTA et al. 2018), for the medieval poet Petrarch (CARRARA and BEZZI 2018), for the mesolithic man of Mondeval, and for the Ptolemaic mummy of the first priest of Toth in Helipolis (CARRARA and SCATTOLIN 2018). Despite this, aFFR is not the only techniques we used in this field: between 2012 and 2013 we developed a new paleoartistic methodology in order to reconstruct the faces of our ancestors. We called this new methodology "Coherent Anatomical Deformation" (BEZZI 2016) and it is based on a x-ray tomography of a Pan troglodytes (Chimpanzee), adapted to the cranium of different hominess’s. Rarely we used also a third technique: an Iconographic Facial Reconstruction, based on a comparison of historical images of a subject. This is the case, for instance, of the Cardinal Bernardo Clesio (NEBL 2018), whose face was reconstructed on ancient paintings and sculptures, after analysing the common features all the portraits.  
Today I will consider this third techniques, speaking about a software I fond yesterday. This software is pretty recent (2017) and, unfortunately, we did not know it when we were working on the exhibition "Imago animi" (BEZZI et al. 2018), because it would have been useful for the facial reconstruction of Bernardo Clesio. This program is referenced as "Large Pose 3D Face Reconstruction from a Single Image via Direct Volumetric CNN Regression", which is also the title of the related article (JACKSON et al. 2017). Of course the software is Open Source and here you can find the code.
Yesterday I played around with it and here below are some results. I started with some test concerning the new exhibition we are working in these days, about the history of my hometown: Cles. Our task for the exhibition is to prepare the archaeological session, so I started trying to automatically reconstruct the face of Luigi Campi, a famous archaeologist born in Cles. To do it I used an historical picture and here below is the result.

Luigi Campi: on the left the original picture, on the right the reconstructed face in 3D.
After this first positive test I wanted to try if the software was able to work also with other kind of historical iconographic sources, so I tried to find a good quality paint of someone related with Cles and finally I found the  portrait of Giuseppina Cles, painted by Giovanni Battista Lampi the Elder around 1780/1781. Also this image gave me positive results.

The reconstruction of Giuseppina Cles from an ancient paint
At this point I wanted to know if the software was also able to work with less realistic images, so I tried to reconstruct the face of the Christ Panthocrator of an ancient fresco in the church of St. Vigilio in Pez and here below is the result.

3D facial reconstruciotn of the Christ Panthocrator fo S. Vigilio in Pez
Befor to stop playing with this very interesting software, I wanted to do some more test with a couple of iconic images, so I tried out the portrait of the Boy Eutyches (from Fayum...

3D of Boy Eutyches
 ... and the Monna Lisa.





After all these test, my opinion about the software is that this tool can be very useful for IFR (Iconographic Facial Reconstruction), in order to get fast 3D model of faces from different historical source to automatize the comparison stage between the different portrait and find the common features. This second stage could be done with a face recognition software, able to compare 3D models.

I hope this post will be useful. Have a nice day!


Bibliografy


Bezzi L., Bezzi A., Moraes C. (2019). "Ricostruzione Facciale Forense di S. Caterina Fieschi Adorno".

Bezzi L., Carrara N, Nebl M. (2018). "Imago animi. Volti dal passato".

Carrara N., Bezzi L. (2018). "Lo strano caso del cranio di Francesco Petrarca".


Carrara N., Scattolin G. (2018). "La mummia del primo sacerdote di Thot

Jackson A. S.,  Bulat A., Argyriou V.,  Tzimiropoulos G. (2017). "Large Pose 3D Face Reconstruction from a Single Image via Direct Volumetric CNN Regression".

Nebl M. (2018). "Il volto di Bernardo Cles".

Zanatta A., Bezzi L., Carrara N., Moraes C., Thiene G., Zampieri F. (2018). "New technique in facial reconstruction: the case of Giovanni Battista Morgagni".

Friday 27 March 2020

3DHOP for speleoarchaeology

Hello everybody,
today I go on writing about our speleoarchaeological project on the natural cave "Bus dela Spia". I prepared some material to share in later post, about the work-flow I followed in Blender, MeshLab, CloudComaper and GRASS GIS, but in the meantime I want to show the final result of my work in recovering old documentation (maps and sections), thanks to the FLOSS 3DHOP.
If you are a regular reader of ATOR, you know what I am speaking about. The software is developed by the Italian CNR (ISTI) and, more precisely, by the Visual Computin Lab (the same programmers who write the code of MeshLab). I chose this software due to its nice "slicer" tool, which allow the user to virtually cut a 3D model along one of the axis, to see other models hidden below (of course this is very useful in archaeology). This in not the only interesting tool (especially considering the updates of the last release), but, by now, is the one I want to show, also because I use it very often in another archaeological field: the Forensic Facial Reconstruction (in order to cut the face and show the cranium). Here below is a short video about this tool. Within 3DHOP are loaded 2 object: the Digital Terrain Model of the landscape and the 3D reconstruction of the "Bus dela Spia", performed in Blender. I hope you will enjoy it. Have a nice day!


Wednesday 25 March 2020

Speleoarchaeology: recovering old maps in 3D

Hello everybody,
during these days I am working on a speleoarchaeological project regarding a cave called "Bus dela Spia" ("Spy's hole") in Trentino. I already wrote about our first mission in this environment, looking of archaeological evidences. The data I am working on now comes from a new exploration, performed in January 2020.
I will report soon more details about the second mission, but now I would like to share a short video showing the result of a test I did to try to recover some old maps and sections to use them as base cartography for our project, which was focused on the 3D documentation of some specific AOI (Area Of Interest).
Here below is an image showing the old documentation of the "Bus dela Spia", based on past speleological explorations (supported by underwater spelunking activities). As you can see, despite the same scale-bar, the map and the section report different values on the X axis. This is due to the fact that the section does not follow a linear path, since the cave, obviously, is not straight, but, while the 3D path of the of the map has been projected, as usual, on a bi-dimensional plane, the section has been "enrolled", reducing (avoiding?) any projection.

The old documentation (map and section) of the "Bus dela Spia"

To manage this kind of data in an easier way I tried to restore in Blender their original shape in 3D. I will describe this process in future post on ATOR, by now, as I said, I just show the result with the video below.



I will use this raw 3D model to position our 3D documentation of some archaeological evidences, performed via SfM -MVS, trying, in the meantime, to recover some old laserscan data (2009).
I hope this post will be useful, if you will ever have the same problem (in combining map and section of old documentation). I will try to publish more detail about the work-flow ASAP. Have a nice day! 

Monday 23 March 2020

ATOR Project Manager: presentation online

Hello everybody,
despite the difficulties of these days (for COVID-19), we try to go on with normal life and trying to keep ATOR up to date is one of the few tasks we can accomplish from home.
This short post is to report the news that Stefano Campus (one of the organizer of the Italian FOSS4G conference 2020) just notified me: all the presentations have been released freely on internet, within the platform Zenodo. The material is published with open licenses and has a specific DOI.
Here you can see all the presentations of the Italian FOSS4G 2020 (which was held in Turin) and here is a direct link to our slides, about the prototype of Virtual Vocal Assistant for archaeology we are working on, thanks to our friend Andres Reyes.


Have a nice day ("It can't rain all the time")!

Wednesday 19 February 2020

ATOR Poject Manager

hello everybody,
this fast post is to let you know that we are going on working on our archaeological project manager, based on a VUI (Voice User Interface).
Today we will present it on the FOSS4G-it 2020, the annual Italian meeting about Free and Open Source geographical  data and software.
We will upload soon new code on our GitLab repository, in the meantime, if you are interested, I uploaded a short video of one of the test we did on the excavation.


Have a nice day!


Friday 31 January 2020

3D printing of the Roman cadastral tablet of Corte Sgarzerie (Verona)

Hello everybody,
this short post is to share the presentation we did yesterday in the "Accademia di Agricoltura, Scienze e Lettere" of Verona. This presentation is part of a bigger project in which we were involved by the Cultural Association Archeonaute.
Basically we have been hired to enhance two archaeological sites in Verona: the Roman Villa of Valdonega and the ancient Capitolium, which is now under the medieval Corte Sgarzerie. I will write later about the whole project, since the presentation of yesterday was focused on a single phase of our work: the 3D reproduction of an unique archaeological find, the so-called "Catasto A" (a Roman cadastrial bronze tablet).
Here below is the video, I hope it can be useful for someone. Have a nice day!




PS
The video by now is just in Italian, but if someone want to help us in adding English subtitles, I let this possibility on YouTube.

Tuesday 21 January 2020

360-degree video for speleoarchaeological explorations

Hello everybody,
this fast post is to public a preliminary test we performed with a 360-degree video, during the second speleoarchaeological exploration of the natural cave called "Bus dela Spia" (here the report of our first mission).
Personally I think that 360-degree photos and video have good potential to enhance the tourist fruition of "Hidden Cultural and Natural Heritage", granting an accessibility based on VR and WebVR applications to a wider public. 
We will go on in performing new test with this technology (also with better resolution) in "extreme" archaeological contests. I hope we will write some feedback soon, in the meantime, here is the video:


    
Have a nice day!

Sunday 19 January 2020

Archaeological Project Manager, code online

Hello everyone,
this fast post is to notify you that finally we upload some code of the Archaeological Project Manager we are developing thanks to our friend Andres Reyes (expert in NLP and Virtual Assistants). The current prototype is build on top of Amazon Alexa and you can find more info in the post I wrote some weeks ago. If you want to help us with the project or see the code, here is the direct link to GitLab.

The source code of APM (on GitLab)
Sorry for the delay, but in these weeks we are all very busy. Hopefully we will upload soon some updates. Stay tuned and have a nice day!
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