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issue151:tutoriel2 [2019/11/30 13:49]
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issue151:tutoriel2 [2019/12/09 21:16] (Version actuelle)
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-In this day and age, photography is rife. We all carry around digital cameras integrated into our smartphones that vie with professional grade equipment from a couple of decades ago. Moreover, we can take just about as many shots, and in higher quality, as anybody ​(other than a professional or an advanced enthusiast) could have done until very recently. We are also rather ​well-equipped - from a software standpoint - to manage and modify our pictures, altering them for different purposes. However, this situation is not the result of an abrupt change in our photographic habits: I am sure many readers of these columns have a history of taking photos in earlier times, perhaps using rather less capable digital equipment, or even physical films developed using a chemical process. I know I still retain several boxes of such at home, hundreds of paper prints, as well as the cameras that I used to take them. Though they may seem quaint and perhaps better suited to a small museum than to a modern lifestyle, it is no less true that these pictures bring back memories of times gone by, of places and of people - some of whom are no longer in this world. In addition, I also conserve several photos made by other people, related to family circumstances,​ but at earlier dates. I have absolutely no doubt I am not the only one in this situation. ​+**In this day and age, photography is rife. We all carry around digital cameras integrated into our smartphones that vie with professional grade equipment from a couple of decades ago. Moreover, we can take just about as many shots, and in higher quality, as abody (other than a professional or an advanced enthusiast) could have done until very recently. We are also r sather ​well-equipped - from a software standpoint - to manage and modify our pictures, altering them for different purposes. However, this situation is not the result of an abrupt change in our photographic habits: I am sure many readers of these columns have a history of taking photos in earlier times, perhaps using rather less capable digital equipment, or even physical films developed using a chemical process. I know I still retain several boxes of such at home, hundreds of paper prints, as well as the cameras that I used to take them. Though they may seem quaint and perhaps better suited to a small museum than to a modern lifestyle, it is no less true that these pictures bring back memories of times gone by, of places and of people - some of whom are no longer in this world. In addition, I also conserve several photos made by other people, related to family circumstances,​ but at earlier dates. I have absolutely no doubt I am not the only one in this situation. ​**
  
-As may or may not seem logicalI would now like to retrieve some of these documentsand work on them to enhance their technical quality thatin caseshas been sadly let down by what was possible at the timeSome images are faded and yellow from the oxidation of their pigmentsOthers have creases and dots on themThe earliest are in black-and-whitewhich is fine from an artistic point of viewbut to which I would like to add color to try and capture some essence of the original scenes+Aujourd'​huila photographie est omniprésente. Nous nous baladons tous avec un appareil-photo intégré à nos smartphones qui vaut ce qu'​était l'​équipement professionnel d'il y a quelque dizaines d'​années. De plusnous pouvons prendre plus d'​instantanéset de meilleure qualitéque n'​importe qui (en dehors des professionnels et des fans expérimentés) pouvait le faire encore récemmentNous sommes aussi plutôt bien équipés -d'un point de vue logiciel - pour gérer et modifier nos photosen les travaillant de différentes manièresCependant, cette situation n'est pas le résultat d'une modification brutal de habitudes photographiques ; je suis sûr que beaucoup de lecteurs de cet article peuvent parler de la prise de vue dans les temps anciens, utilisant peut-être un équipement numérique plutôt faiblement puissant, ou des pellicules développées avec un procédé chimique. Je sais que je garde encore à la maison plusieurs boîtes de celles-cides centaines de photos papier ainsi que les appareils que j'ai utilisé pour les prendre. Bien qu'ils paraissent pittoresques et peut-être mieux faits pour un petit musée que pour un style de vie moderneil n'en n'est pas moins vrai que ces photos font remonter des souvenirs des temps passés, des lieux et de gens, certains n'​étant plus maintenant de ce monde. De plus, je conserve aussi des photos faites par d'​autres,​ liées à des circonstances familiales, mais à des dates plus lointaines. Je n'ai absolument aucun doute que je ne suis pas le seul dans ce cas.
  
-This has been the main source of inspiration for this seriesin which will be going on my internal journey of learning ​to make something ​of the old photos in my possession, and others in the public domain due to their age. You, the reader, ​are welcome to tag along, ​and I hope to glean some small insight and perhaps an idea or two from time to time. No promises are made as to the quality ​of the content, or potential errors ​and omissionsI am a computer scientist, not a true artist or a professional of image restoration. So please take all this as a best effort, but with no firm guarantees ​much as is the case of most open-source software. Naturallybeing a Linux user, that is what I will be using: open-source applications,​ on top of an open-source operating system: Linux Mint 19.2 in my casethough there should be no real differences between anything described here and other comparable distributions in the Ubuntu family, or Debian.+**As may or may not seem logical, I would now like to retrieve some of these documents, and work on them to enhance ​their technical quality thatin cases, has been sadly let down by what was possible at the time. Some images ​are faded and yellow ​from the oxidation ​of their pigments. Others have creases ​and dots on themThe earliest are in black-and-whitewhich is fine from an artistic point of viewbut to which I would like to add color to try and capture some essence of the original scenes
  
-A choice of program+This has been the main source of inspiration for this series, in which I will be going on my internal journey of learning to make something of the old photos in my possession, and others in the public domain due to their age. You, the reader, are welcome to tag along, and I hope to glean some small insight and perhaps an idea or two from time to time. No promises are made as to the quality of the content, or potential errors and omissions. I am a computer scientist, not a true artist or a professional of image restoration. So please take all this as a best effort, but with no firm guarantees - much as is the case of most open-source software. Naturally, being a Linux user, that is what I will be using: open-source applications,​ on top of an open-source operating system: Linux Mint 19.2 in my case, though there should be no real differences between anything described here and other comparable distributions in the Ubuntu family, or Debian.** 
 + 
 +Que ça paraisse logique ou pas, j'​aimerais maintenant retrouver certains de ces documents et les retravailler pour améliorer leur qualité technique, qui dans certains cas, s'est tristement dégradée du fait de cequi était possible à l'​époque. Certaines images affadies et jaunies par l'​oxydation de leurs pigments. D'​autres conportent des plis ou des taches. Les plus anciennes sont en noir et blanc, ce qui est bien d'un point de vue artistique, mais auxquelles j'​aimerai ajouter de la couleur pour essayer de capturer l'​essentiel des scènes originales. 
 + 
 +C'est ce qui a été ma source d'​inspiration principale pour cette série, dans laquelle je poursuivre mon voyage interne d'​apprentissage pour faire quelque chose des ces vieilles photos en ma possession, et d'​autres du domaine public du fait de leur age. Vous lecteur, vous êtes bienvenu pour suivre et, j'​espère,​ pour glaner quelques petites indications et peut-être une idée ou deux de temps en temps. Je ne promets rien quand à la qualité du contenu et les potentielles erreurs ou omissions. Je suis scientifique dans l'​informatique et pas un véritable artiste ou un professionnel de la restauration des images. ​ Aussi, merci d'​accueillir tout cela come mon meilleur effort, mais sans garanties solides - comme beaucoup de logiciels Open Source. Naturellement,​ étant un utilisateur de Linux, voilà ce que je vais utiliser : des applications Open Source, tournant sur un système d'​exploitation Open Source, Linux Mint 19.2 dans mon cas bien qu'il n'y aura aucune vraie différence entre tout qui sera décrit ici et d'​autres distributions comparables dans la famille Ubuntu, ou Debian. 
 + 
 +**A choice of program
  
 Modern distributions of GNU/Linux propose many programs to work on photographs and other forms of digital art. Some applications,​ such as Inkscape, are oriented towards creating vector graphics, not photos and raster images. Others, such as Darktable, are used to process raw images fresh from a digital camera, for management, and to quickly apply effects and enhancements to the complete image. And then, there are the many general-purpose applications with a wide range of effects and tools for editing complete images, but also drawing and modifying local details. Perhaps the best-known of these is the GNU Image Manipulation Program (GIMP), often installed within a distribution’s default selection of software. A good stand-in for Adobe’s commercial Photoshop, it can certainly be used for our purposes and to good effect. Modern distributions of GNU/Linux propose many programs to work on photographs and other forms of digital art. Some applications,​ such as Inkscape, are oriented towards creating vector graphics, not photos and raster images. Others, such as Darktable, are used to process raw images fresh from a digital camera, for management, and to quickly apply effects and enhancements to the complete image. And then, there are the many general-purpose applications with a wide range of effects and tools for editing complete images, but also drawing and modifying local details. Perhaps the best-known of these is the GNU Image Manipulation Program (GIMP), often installed within a distribution’s default selection of software. A good stand-in for Adobe’s commercial Photoshop, it can certainly be used for our purposes and to good effect.
  
-However, for this series I have preferred to focus on a different program, Krita, that is perhaps slightly less well-known to the general community outside of people involved in visual art, being more focused towards artistic drawing than GIMP. It came to my attention when researching software to use with the recent acquisition,​ a digital tablet, with which it integrates very nicely. ​+However, for this series I have preferred to focus on a different program, Krita, that is perhaps slightly less well-known to the general community outside of people involved in visual art, being more focused towards artistic drawing than GIMP. It came to my attention when researching software to use with the recent acquisition,​ a digital tablet, with which it integrates very nicely. ​** 
 + 
 +Un choix de programme 
 + 
 +Les distributions modernes de GNU/Linux proposent beaucoup de programmes pour travailler sur des photos et d'​autres formes d'art numérique. Certaines applications,​ comme Inkscape, sont orientées vers le dessin vectoriel, pas les photos ou les images raster (bitmap). D'​autres,​ telles que Darktable, sont utilisées pour triater des images raw directement depuis l'​appareil-photo numérique, pour leur gestion et pour appliquer rapidement des effets et des améliorations de l'​image entière. Et puis, il y a beaucoup applications d'​usage général avec un large choix d'​effets et d'​outils pour la modification des images entières, mais aussi pour dessiner et modifier des détails locaux. Peut-être que le plus connu de ceux-ci est « GNU Image Manipulation Program » (GIMP - Programme de manipulation d'​image de GNU), souvent installé dans la sélection des logiciels par défaut d'une distribution.C'​est une bonne alternative pour le logiciel payant Photoshop ; il peut certainement être utilisé pour nos besoins, avec de bons résultats. 
 + 
 +Cependant, pour cette série, j'ai préféré me focaliser sur un programme différent, Krita, qui est eput-être légèrement moins connu de la communauté générale, en dehors des gens qui s'​occupent d'art visuel, etant plus focalisé sur le dessin artistique que GIMP. Il a été porté à mon attention en faisant une recherche de logiciels à utiliser avec ma récente acquisition,​ un tablette numérique, avec laquelle il s'​intègre très agréablement. .  
 + 
 +**Krita is based on the Qt widget set, and thus often associated with the KDE Plasma desktop. But, as with most modern applications,​ it does integrate rather well with other desktop managers such as Gnome or Cinnamon, and, in fact, I tend to use it with a fairly standard Linux Mint. Other options include using Krita under Mac OS, or Windows. Further information may be found on the project’s home page, at https://​krita.org/​en/​. As usual with Ubuntu and its derivatives,​ installation is usually a matter of using terminal commands: 
 + 
 +sudo apt update ; sudo apt install krita 
 + 
 +Krita should also be easily available in graphical software managers, though I cannot say I have tried out that route.**
  
-Krita is based on the Qt widget setand thus often associated with the KDE Plasma ​desktopButas with most modern ​applications, ​it does integrate rather well with other desktop managers such as Gnome or Cinnamon, ​andin factI tend to use it with a fairly standard ​Linux Mint. Other options ​include using Krita under Mac OS, or Windows. ​Further information may be found on the project’s home page, at https://​krita.org/​en/. As usual with Ubuntu ​and its derivatives, installation ​is usually a matter of using terminal commands:+Krit est basé sur l'​ensemble de gadgets ​Qt, et, donc, souvent associé au bureau ​KDE Plasma. ​Maiscomme beaucoup d'applications ​modernes, il s'​intègre plus bien avec d'​autres gestionnaires de bureau comme Gnome ou Cinnamon, ​eten faitj'ai tendance à l'​utiliser avec un Linux Mint assez ordinaireD'​autres ​options ​comprennent l'​utilisation de Krita sous Mac OS ou Windows. ​D'​autres informations peuvent être trouvées sur la page '​accueil du projetà https://​krita.org/​fr/. Comme habituellement avec Ubuntu ​et ses dérivéspour l'installation, il est question des commandes suivantes ​:
  
 sudo apt update ; sudo apt install krita sudo apt update ; sudo apt install krita
  
-Krita should also be easily available in graphical software managersthough I cannot say I have tried out that route.+Krita est en général disponible aussi dans les gestionnaires graphiques de logicielsbien que je ne puisse rien dire, n'​ayant pas explorer ce chemin.
  
-Acquiring the images+**Acquiring the images
  
-Before working on any specific images, they must, at some point, be converted to a format compatible with computers. Pictures taken with digital cameras may be stored on hard drives, or even USB-connected pen-drives. These formats will usually give no problem, as long as some means of connection is available. The situation may become more complex with the CD-ROMs that many camera-film developers provided alongside paper copies in the final years of chemical film usage - since most modern computers lack an optical drive. An older laptop may be of use, though I would advise a liberal application of compressed air to clean some of the accumulated dust out before putting such bask in use reading CDs. An external CD reader connected to our main computer via USB may be a better alternative;​ these are not expensive and may be stored for other purposes.+Before working on any specific images, they must, at some point, be converted to a format compatible with computers. Pictures taken with digital cameras may be stored on hard drives, or even USB-connected pen-drives. These formats will usually give no problem, as long as some means of connection is available. The situation may become more complex with the CD-ROMs that many camera-film developers provided alongside paper copies in the final years of chemical film usage - since most modern computers lack an optical drive. An older laptop may be of use, though I would advise a liberal application of compressed air to clean some of the accumulated dust out before putting such bask in use reading CDs. An external CD reader connected to our main computer via USB may be a better alternative;​ these are not expensive and may be stored for other purposes.**
  
-Some time ago, flatbed scanners were a widely-used peripheral to convert physical documents to digital form. I still have one on a shelf somewhere, which I could plug in and use in conjunction with the Simple Scan software that comes with Ubuntu these days. However, I will not be using it to convert paper prints to digital form for the following reason. My desktop scanner, like most, has a resolution of 300 dpi (dots per inch). When applied to a standard paper print of about 4 by 6 inches, or 10 by 15 cm, this gives a digital file with resolution 1200 x 1800 pixels. But my cheap Samsung phone has a camera with a resolution that goes up to 4128 x 3096 pixels (13 Megapixels). So one can achieve both better resolution and an easier workflow to transfer the images to a computer by simply taping the prints to a vertical wall in a well-illuminated place, and taking a picture of them with the mobile phone’s camera. This is the miracle of technology ever moving forward. Just make sure to take the photos from a point as squarely in front of the original as possible, and do not let shadows or the use of a flash mar the result.+**Some time ago, flatbed scanners were a widely-used peripheral to convert physical documents to digital form. I still have one on a shelf somewhere, which I could plug in and use in conjunction with the Simple Scan software that comes with Ubuntu these days. However, I will not be using it to convert paper prints to digital form for the following reason. My desktop scanner, like most, has a resolution of 300 dpi (dots per inch). When applied to a standard paper print of about 4 by 6 inches, or 10 by 15 cm, this gives a digital file with resolution 1200 x 1800 pixels. But my cheap Samsung phone has a camera with a resolution that goes up to 4128 x 3096 pixels (13 Megapixels). So one can achieve both better resolution and an easier workflow to transfer the images to a computer by simply taping the prints to a vertical wall in a well-illuminated place, and taking a picture of them with the mobile phone’s camera. This is the miracle of technology ever moving forward. Just make sure to take the photos from a point as squarely in front of the original as possible, and do not let shadows or the use of a flash mar the result.**
  
-Series outline+**Series outline
  
 In the next part of this series, we will commence work on a simple landscape, a photo of the castle of Foix in southern France about the turn of the century. With the passage of time, this photo is now slated to fall within the public domain. It has already been digitized by the Rosalis project of the municipal public library of Toulouse, and may be downloaded from Wikicommons at address: https://​commons.m.wikimedia.org/​wiki/​File:​Ch%C3%A2teau_en_ruines_(8056081904).jpg .  In the next part of this series, we will commence work on a simple landscape, a photo of the castle of Foix in southern France about the turn of the century. With the passage of time, this photo is now slated to fall within the public domain. It has already been digitized by the Rosalis project of the municipal public library of Toulouse, and may be downloaded from Wikicommons at address: https://​commons.m.wikimedia.org/​wiki/​File:​Ch%C3%A2teau_en_ruines_(8056081904).jpg . 
  
-Interested viewers may wish to download this image, explore its various technical difficulties as a restoration project, and perhaps play around a little before the next episode. Until then, take care!+Interested viewers may wish to download this image, explore its various technical difficulties as a restoration project, and perhaps play around a little before the next episode. Until then, take care!**
  
issue151/tutoriel2.1575118185.txt.gz · Dernière modification: 2019/11/30 13:49 par auntiee