Contrôler le traitement des images.
traitement de l’image
- always use LittleCMS 2 to apply output color profile
- If this option is activated, Ansel will use the LittleCMS 2 system library to apply the output color profile instead of its own internal routines. This is significantly slower than the default but might give more accurate results in some cases.
Remarque : Si l’ICC donné est basé sur une LUT ou contient à la fois une LUT et une matrice, Ansel utilisera LittleCMS2 pour rendre les couleurs quelle que soit la valeur de ce paramètre (par défaut désactivé).
- pixel interpolator (warp)
- The pixel interpolator used for rotation, lens correction, liquify, crop and final scaling.
Chaque fois que nous redimensionnons ou déformons une image, nous devons choisir un algorithme d’interpolation de pixels (voir wikipedia pour plus de détails). Pour les modules de déformation, Ansel propose les méthodes : bilinéaire, bicubique ou lanczos2. Dans la plupart des cas bicubique est une option sûre, c’est la valeur par défaut.
- interpolations des pixels (mise à l’échelle)
- L’interpolateur de pixels utilisé pour la mise à l’échelle. Les mêmes options sont fournies que pour les modules de déformation, mais avec lanczos3 en plus.
lanczos3 peut provoquer des dépassements de pixels conduisant à des artefacts mais donne parfois un aspect plus net. Cette option n’est donc fournie que pour les algorithmes de transformation (mise à l’échelle) et c’est la valeur par défaut.
- 3D lut root folder
- Define the root folder (and sub-folders) containing Lut files used by the lut 3D module
- détecter les miniatures monochromes
- Activez cette option pour analyser les images lors de l’importation et les étiqueter avec le mot-clé
chambre noire|mode|monochromesi elles sont monochromes. L’analyse est basée sur l’aperçu intégré dans le fichier importé. Cela permet un flux de travail plus pratique lorsque vous travaillez avec des images monochromes, mais cela ralentit l’importation, ce paramètre est donc désactivé par défaut.
CPU, GPU, Memory
- Ansel resources
- Choose how much of your system and graphics card (GPU) memory will be used by Ansel. Four options are provided by default:
- small takes roughly 20% of your system memory and 40% of your GPU memory. This might be acceptable on very large systems, especially if you’re not exporting images. Mostly, though, this can only be recommended if you are using a lot of other demanding applications at the same time as Ansel.
- default takes roughly 60% of your system memory and 70% of your GPU memory. This mode is recommended if you’re not exporting a lot of images, have at least 16Gb of system memory and 4Gb of GPU memory, and also are running a lot of other application at the same time as Ansel.
- large takes roughly 75% of your system memory and 90% of your GPU memory. This is the best option if you are only using Ansel on your system and/or are exporting a lot of images.
- unrestricted is not generally recommended. In this mode Ansel may attempt to use more memory than your system has available. This might be possible if your system uses swapping when all of its system memory is taken, but it could lead to system instability. Use this mode with care, only when exporting very large images that Ansel cannot otherwise handle.
- See the memory & performance tuning section for more information.
- utilisation du disque dur pour le cache des miniatures
- Si activé, Ansel stocke toutes les miniatures sur le disque dur en tant que cache secondaire, et les garde ainsi accessibles si elles sont supprimées du cache principal. Cela nécessite plus d’espace disque mais accélère la vue lighttable car cela évite le retraitement des miniatures (activé par défaut).
- enable disk backend for full preview cache
- If enabled, Ansel writes full preview images to disk (
.cache/Ansel/) when evicted from the memory cache. Note that this can take a lot of storage (several gigabytes for 20k images) and Ansel will never delete cached images. It’s safe to delete these manually if you want. Enabling this option will greatly improve lighttable performance when zooming an image in full preview mode (default off). - activate OpenCL support
- Your GPU can be used by Ansel to significantly speed up processing. The OpenCL interface requires suitable hardware and matching OpenCL drivers on your system. If one of those is not found the option is grayed out. Can be switched on and off at any time and takes immediate effect (default on).
- OpenCL scheduling profile
- Defines how preview and full pixelpipe tasks are scheduled on OpenCL enabled systems:
- default: the GPU processes the center view pixelpipe; the CPU processes the preview pipe,
- very fast GPU: both pixelpipes are processed sequentially on the GPU.
- multiple GPUs: both pixelpipes are processed in parallel on different GPUs – see the multiple devices section for more information,
- tune OpenCL performance
- Defines how Ansel will attempt to tune OpenCL performance for your system. The following options are provided (default nothing):
- nothing: do not attempt to tune OpenCL performance.
- memory size: this parameter currently (by default) applies a fixed 400MB headroom to all devices and assumes the remainder (total device memory less 400MB) is available for OpenCL module processing. You can also choose to amend this value or have Ansel attempt to auto-detect available memory by changing a parameter in your
Anselrcfile. Please see the memory & performance tuning section for more details. If you choose to enable auto-detection, switching this parameter off and on again will force a re-detection at the next pipe run.
- memory size: this parameter currently (by default) applies a fixed 400MB headroom to all devices and assumes the remainder (total device memory less 400MB) is available for OpenCL module processing. You can also choose to amend this value or have Ansel attempt to auto-detect available memory by changing a parameter in your
- memory transfer: when Ansel needs more memory than it has available, it breaks your images into tiles, which are processed separately. When tiling, Ansel frequently needs to transfer data between system and GPU memory. This option tells Ansel to use a special copy mode (pinned memory transfer), which can be faster, but can also require more memory on some devices. On other devices it might degrade performance. There is no safe general way to predict how this option will function on a given device so you will have to test it for yourself. If you have multiple devices, you can switch pinned memory transfer on or off on a “per device” basis by directly editing your Anselrc file.
- memory size and transfer: use both tuning mechanisms.
- See the memory & performance tuning section for more information.
Libraw
Ansel uses the Rawspeed library by default to decode raw image files. Rawspeed is flawlessly integrated in Ansel, but does not support Canon .CR3 files yet. For this reason, a basic support of Libraw has been implemented such that owners of recent Canon cameras can still decode their files. Libraw also tends to support new formats faster than Rawspeed.
The options of this section allow users to force the use of Libraw for any picture they want, using rules based on file extension and camera/vendor EXIF metadata. The feature is brittle and unsafe in general because we don’t check and sanitize every possible flavour of encoding.
- Supported files
- Canon
.CR3
- Canon
- Files that seem to be working
- Olympus
.ORF - Hasselblad
.3FR - Nikon
.NEFnon-compressed
- Olympus
- Files that definitely don’t work and make the software crash
- Nikon sRAW and compressed
.NEF - Phase One
.IIQ
- Nikon sRAW and compressed
Warning
The library used to decode files is remembered at the application level, globally, not for each file. Editing pictures decoded by Libraw may not produce the exact same result if you revert to Rawspeed in the future. You should really stick to Rawspeed whenever possible.
You are strongly advised to save any edited picture to 16 bits TIFF at full resolution using Rec2020 linear color space as an archival backup of your work, and not rely on the consistency of the non-destructive editing result in the future.
- Raw file extensions to load through Libraw
- case-insensitive, coma-separated list of the file extensions. Default :
cr3. - Camera models to load through Libraw
- case-insensitive, coma-separated list of the camera models as they appear in the Display metadata module, under the model field. You may have to enable this field using the preferences of the module if it does not appear in the widget.
- Camera makers to load through Libraw
- case-insensitive, coma-separated list of the camera manufacturers as they appear in the Display metadata module, under the maker field. You may have to enable this field using the preferences of the module if it does not appear in the widget.
Note
For Canon files using the.CR3 format, the model and maker metadata are not decoded properly and left blank. You have to filter them mandatorily by file extension.To debug this feature :
- Start Ansel in command line using
ansel -d imageio. For each loaded image, it will tell which library was used to decode it, - If the settings you input make the software crash at startup, remove the
libraw/extensions,libraw/models,libraw/makersconfiguration keys in theanselrcconfiguration file, located in~./config/anselfolder on Linux and Mac, orAPPDATA\.config\anselon Windows.