The Floating Point Engine - Revision history

DrSlony at 21:22, 9 December 2019

2019-12-09T21:22:40Z

← Older revision		Revision as of 21:22, 9 December 2019
Line 1:		Line 1:
			<div class="pagetitle">The Floating-Point Engine</div>

	RawTherapee performs all calculations in 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] precision (in contrast to 16-bit integer as used in many other converters such as [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0).		RawTherapee performs all calculations in 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] precision (in contrast to 16-bit integer as used in many other converters such as [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0).

DrSlony at 18:51, 2 March 2019

2019-03-02T18:51:26Z

← Older revision		Revision as of 18:51, 2 March 2019
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	* Non-raw		* Non-raw
	** 8-bit: <code>(width * height * 3) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>		** 8-bit: <code>(width * height * 3) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>
	** 16-bit: <code(width * height * 3 * 2) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>		** 16-bit: <code>(width * height * 3 * 2) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>
	** 32-bit: <code(width * height * 3 * 4) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>		** 32-bit: <code>(width * height * 3 * 4) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>
	* Raw		* Raw
	** <code>(width * height * 4) + (width * height * 4) + (width * height * 12) + (previewWidth * previewHeight * 28)</code>		** <code>(width * height * 4) + (width * height * 4) + (width * height * 12) + (previewWidth * previewHeight * 28)</code>

DrSlony: /* Memory Requirements */

2019-02-11T21:32:27Z

Memory Requirements

← Older revision		Revision as of 21:32, 11 February 2019
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	** 32-bit: <code(width * height * 3 * 4) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>		** 32-bit: <code(width * height * 3 * 4) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>
	* Raw		* Raw
	** <code>(width * height * 4) + (width * height * 12) + (previewWidth * previewHeight * 28)</code>		** <code>(width * height * 4) + (width * height * 4) + (width * height * 12) + (previewWidth * previewHeight * 28)</code>

	Some overhead memory is additionally required, for example for generating thumbnails of other images which reside in the opened image's folder.		Some overhead memory is additionally required, for example for generating thumbnails of other images which reside in the opened image's folder.

	The memory requirement for processing and saving an image depends on what tools you use and can vary significantly from the above - the above pertains only to opening an image.		The memory requirement for processing and saving an image depends on what tools you use and can vary significantly from the above - the above pertains only to opening an image.

DrSlony: /* Memory Requirements */

2019-02-11T21:29:27Z

Memory Requirements

← Older revision		Revision as of 21:29, 11 February 2019
Line 17:		Line 17:
	== Memory Requirements ==		== Memory Requirements ==

	To open an image in the Editor, RawTherapee 5.6 needs roughly this much RAM, in bytes:		To open an image in the Editor, RawTherapee 5.6 needs very roughly this much RAM, in bytes:
	* Non-raw		* Non-raw
	** 8-bit: <code>3 * width * height</code>		** 8-bit: <code>(width * height * 3) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>
	** 16-bit: <code>3 * width * height * 2</code>		** 16-bit: <code(width * height * 3 * 2) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>
	** 32-bit: <code>3 * width * height * 4</code>		** 32-bit: <code(width * height * 3 * 4) + (width * height * 4) + (previewWidth * previewHeight * 28)</code>
	* Raw		* Raw
	** ~~Anywhere between~~ <code>width * height * ~~26</code> and <code>~~width * height * 40</code>~~, as raw images require memory for the raw data, the demosaiced data, the preview image (which depends on your screen resolution and whether you're running in HiDPI mode) and some overhead.~~		** <code>(width * height * 4) + (width * height * 12) + (previewWidth * previewHeight * 28)</code>

	The memory requirement for processing and saving an image depends on what tools you use - the above pertains only to opening an image.		Some overhead memory is additionally required, for example for generating thumbnails of other images which reside in the opened image's folder.

			The memory requirement for processing and saving an image depends on what tools you use and can vary significantly from the above - the above pertains only to opening an image.

DrSlony at 20:53, 11 February 2019

2019-02-11T20:53:31Z

← Older revision		Revision as of 20:53, 11 February 2019
Line 14:		Line 14:
	* Ensure that RawTherapee [[Preferences#Directories\|does not load]] dark-frame or flat-field images if you do not use them.		* Ensure that RawTherapee [[Preferences#Directories\|does not load]] dark-frame or flat-field images if you do not use them.
	* Avoid having more than a few hundred photos per folder, as each photo requires a little RAM (thumbnail, embedded ICC profile, etc.).		* Avoid having more than a few hundred photos per folder, as each photo requires a little RAM (thumbnail, embedded ICC profile, etc.).

			== Memory Requirements ==

			To open an image in the Editor, RawTherapee 5.6 needs roughly this much RAM, in bytes:
			* Non-raw
			** 8-bit: <code>3 * width * height</code>
			** 16-bit: <code>3 * width * height * 2</code>
			** 32-bit: <code>3 * width * height * 4</code>
			* Raw
			** Anywhere between <code>width * height * 26</code> and <code>width * height * 40</code>, as raw images require memory for the raw data, the demosaiced data, the preview image (which depends on your screen resolution and whether you're running in HiDPI mode) and some overhead.

			The memory requirement for processing and saving an image depends on what tools you use - the above pertains only to opening an image.

DrSlony at 23:37, 6 January 2019

2019-01-06T23:37:59Z

← Older revision		Revision as of 23:37, 6 January 2019
Line 1:		Line 1:
	~~[[Category:General]]~~

	RawTherapee performs all calculations in 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] precision (in contrast to 16-bit integer as used in many other converters such as [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0).		RawTherapee performs all calculations in 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] precision (in contrast to 16-bit integer as used in many other converters such as [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0).

DrSlony at 23:35, 6 January 2019

2019-01-06T23:35:51Z

← Older revision		Revision as of 23:35, 6 January 2019
Line 16:		Line 16:
	* Ensure that RawTherapee [[Preferences#Directories\|does not load]] dark-frame or flat-field images if you do not use them.		* Ensure that RawTherapee [[Preferences#Directories\|does not load]] dark-frame or flat-field images if you do not use them.
	* Avoid having more than a few hundred photos per folder, as each photo requires a little RAM (thumbnail, embedded ICC profile, etc.).		* Avoid having more than a few hundred photos per folder, as each photo requires a little RAM (thumbnail, embedded ICC profile, etc.).
	* The most memory-intensive tools are [[Tone Mapping]], [[Contrast by Detail Levels]] and [[Exposure#Highlight_Reconstruction \| Highlight Reconstruction]] using "Color Propagation", so you might need to avoid using them if your machine and operating system are not up to standard.

DrSlony at 22:43, 6 January 2019

2019-01-06T22:43:56Z

← Older revision		Revision as of 22:43, 6 January 2019
Line 3:		Line 3:
	RawTherapee performs all calculations in 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] precision (in contrast to 16-bit integer as used in many other converters such as [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0).		RawTherapee performs all calculations in 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] precision (in contrast to 16-bit integer as used in many other converters such as [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0).

	Classical converters work with 16-bit integer numbers. A pixel channel has values ranging from 0-65535 in 16-bit precision (to increase precision, converters usually multiply the 12- or 14-bit camera values to fill the 16-bit range). The numbers have no fractions, so for example there is no value between 102 and 103. In contrast, floating point numbers store a value at a far wider range with a precision of 6-7 significant digits. This helps especially in the highlights, where higher ranges can be recovered. It allows intermediate results in the processing chain to over- or undershoot temporarily without losing information. The fraction values possible also help to smooth color transitions to prevent color banding~~. And not the least, floating point makes life easier for developers who don't need to worry as much about rounding errors or clipping when developing image algorithms for RawTherapee~~.		Classical converters work with 16-bit integer numbers. A pixel channel has values ranging from 0-65535 in 16-bit precision (to increase precision, converters usually multiply the 12- or 14-bit camera values to fill the 16-bit range). The numbers have no fractions, so for example there is no value between 102 and 103. In contrast, floating point numbers store a value at a far wider range with a precision of 6-7 significant digits. This helps especially in the highlights, where higher ranges can be recovered. It allows intermediate results in the processing chain to over- or undershoot temporarily without losing information. The fraction values possible also help to smooth color transitions to prevent color banding.

	The downside is the amount of RAM that floating point numbers require, which is exactly twice that of 16-bit integer. Together with the ever-increasing megapixel count of digital cameras, a 32-bit operating system can quite easily run out of memory and cause RawTherapee to crash. Therefore a 64-bit operating system is highly ~~advised~~ for stability.		The downside is the amount of RAM that floating point numbers require, which is exactly twice that of 16-bit integer. Together with the ever-increasing megapixel count of digital cameras, a 32-bit operating system can quite easily run out of memory and cause RawTherapee to crash. Therefore a 64-bit operating system is highly recommended for stability.

	~~If you have problems running~~ RawTherapee on a 32-bit ~~system, try the following:~~		We officially ended support for 32-bit versions of RawTherapee with release 5.0-r1 in February 2017. Do not file bug reports regarding issues on 32-bit systems.

	* As a ~~general rule~~, ~~you should avoid having folders with too many raw photos in them as each photo takes up memory when displayed in RawTherapee's File Browser tab.~~		If you nevertheless need to use RawTherapee on a 32-bit system, the following will help make the most of it:
	* RawTherapee uses more RAM while you are using the ~~File Browser tab, so avoid opening that tab while you are processing photos.~~
	* Use 4-Gigabyte Tuning in Windows. See "[http://msdn.microsoft.com/en-us/library/bb613473%28VS.85%29.aspx 4-Gigabyte Tuning: BCDEdit and Boot.ini]" for an explanation of what it is, and find out how to do it by reading the guide "[http://avatechsupport.blogspot.se/2008/03/how-to-set-3gb-startup-switch-in.html How to set the /3GB Startup Switch in Windows XP and Vista]".		* Use 4-Gigabyte Tuning in Windows. See "[http://msdn.microsoft.com/en-us/library/bb613473%28VS.85%29.aspx 4-Gigabyte Tuning: BCDEdit and Boot.ini]" for an explanation of what it is, and find out how to do it by reading the guide "[http://avatechsupport.blogspot.se/2008/03/how-to-set-3gb-startup-switch-in.html How to set the /3GB Startup Switch in Windows XP and Vista]".
	* Close other programs while working in RawTherapee.		* Close other programs while working in RawTherapee.
	* ~~Close the Image~~ Editor tab ~~when you're done editing to free up memory~~.		* Use a [[Preferences#Layout\|single Editor tab]].
	* Turn off "auto-start" in the ~~batch queue~~. ~~Only add~~ photos to the ~~batch queue once you are done editing all of~~ them, ~~and then start it. Use the batch queue, do not use the immediate save button.~~		* Turn off "auto-start" in the [[Queue]]. Add photos to the Queue as usual. When ready to start processing them, restart RawTherapee to free up RAM (no image open in the Editor), and start the queue.
	* Change to ~~a directory with few or~~ no ~~photos~~ in ~~it before starting~~ the ~~batch queue.~~		* Ensure that RawTherapee [[Preferences#Directories\|does not load]] dark-frame or flat-field images if you do not use them.
	* You can free some memory by deleting (or moving to a different folder, ~~or renaming to something like .unusedicc) all~~ the ~~.icc profiles in iccprofiles\input for the cameras you do not use~~.		* Avoid having more than a few hundred photos per folder, as each photo requires a little RAM (thumbnail, embedded ICC profile, etc.).
	* ~~Assure~~ that ~~the Dark-frames Directory and the Flat-fields Directory in~~ Preferences do not ~~point to folders containing raw~~-~~files~~ if you do not use ~~Dark-frames or Flat-fields~~.
	* The most memory-intensive tools are [[Tone Mapping]], [[Contrast by Detail Levels]] and [[Exposure#Highlight_Reconstruction \| Highlight Reconstruction]] using "Color Propagation", so you might need to avoid using them if your machine and operating system are not up to standard.		* The most memory-intensive tools are [[Tone Mapping]], [[Contrast by Detail Levels]] and [[Exposure#Highlight_Reconstruction \| Highlight Reconstruction]] using "Color Propagation", so you might need to avoid using them if your machine and operating system are not up to standard.

DrSlony: Revised first paragraph

2019-01-06T22:03:33Z

Revised first paragraph

← Older revision		Revision as of 22:03, 6 January 2019
Line 1:		Line 1:
	[[Category:General]]		[[Category:General]]
	RawTherapee 4 does all calculations in precise 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] notation (in contrast to 16-bit integer as used in many other converters like [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0) so nothing gets rounded off and lost.

	~~Classical converters work with 16-bit integer numbers. A pixel channel has values ranging from 0-65535~~ in ~~16-bit (to increase precision converters usually multiply the 12-14 bit camera values to fill the 16~~-bit ~~range)~~. ~~The numbers have no fractions, so for example there is no value between 102 and 103~~. ~~In contrast,~~ floating point ~~numbers store a value at a far wider range with a~~ precision ~~of 6~~-~~7 significant digits. This helps especially~~ in ~~the highlights, where higher ranges can be recovered~~. ~~It allows intermediate results in the processing chain to over- or undershoot temporarily without losing information~~. ~~The fraction values possible~~ also ~~help~~ to ~~smooth color transitions to prevent color banding~~. ~~And not the least, floating point makes the life easier for developers which don't need to worry as much about rounding errors or clipping when developing image algorithms for RawTherapee~~.		RawTherapee performs all calculations in 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] precision (in contrast to 16-bit integer as used in many other converters such as [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0).

	~~The downside is the RAM space floating point numbers require, which is exactly twice that of~~ 16-bit integer. ~~Together with~~ the ~~ever~~-~~increasing megapixel count of digital cameras a 32~~-bit ~~operating system can quite easily run out of memory and cause RawTherapee~~ to ~~crash. Therefore a 64~~-bit ~~operating system~~ is ~~highly advised for stability~~. ~~If you have problems running RT on~~ a 32-~~bit system~~, ~~try~~ the ~~following:~~		Classical converters work with 16-bit integer numbers. A pixel channel has values ranging from 0-65535 in 16-bit precision (to increase precision, converters usually multiply the 12- or 14-bit camera values to fill the 16-bit range). The numbers have no fractions, so for example there is no value between 102 and 103. In contrast, floating point numbers store a value at a far wider range with a precision of 6-7 significant digits. This helps especially in the highlights, where higher ranges can be recovered. It allows intermediate results in the processing chain to over- or undershoot temporarily without losing information. The fraction values possible also help to smooth color transitions to prevent color banding. And not the least, floating point makes life easier for developers who don't need to worry as much about rounding errors or clipping when developing image algorithms for RawTherapee.

	* As a general rule, you should avoid having folders with too many raw photos in them as each photo takes up memory when displayed in RawTherapee's File Browser tab~~. Try not to have more than 100 photos per folder~~.		The downside is the amount of RAM that floating point numbers require, which is exactly twice that of 16-bit integer. Together with the ever-increasing megapixel count of digital cameras, a 32-bit operating system can quite easily run out of memory and cause RawTherapee to crash. Therefore a 64-bit operating system is highly advised for stability.

			If you have problems running RawTherapee on a 32-bit system, try the following:

			* As a general rule, you should avoid having folders with too many raw photos in them as each photo takes up memory when displayed in RawTherapee's File Browser tab.
	* RawTherapee uses more RAM while you are using the File Browser tab, so avoid opening that tab while you are processing photos.		* RawTherapee uses more RAM while you are using the File Browser tab, so avoid opening that tab while you are processing photos.
	* Use 4-Gigabyte Tuning in Windows. See "[http://msdn.microsoft.com/en-us/library/bb613473%28VS.85%29.aspx 4-Gigabyte Tuning: BCDEdit and Boot.ini]" for an explanation of what it is, and find out how to do it by reading the guide "[http://avatechsupport.blogspot.se/2008/03/how-to-set-3gb-startup-switch-in.html How to set the /3GB Startup Switch in Windows XP and Vista]".		* Use 4-Gigabyte Tuning in Windows. See "[http://msdn.microsoft.com/en-us/library/bb613473%28VS.85%29.aspx 4-Gigabyte Tuning: BCDEdit and Boot.ini]" for an explanation of what it is, and find out how to do it by reading the guide "[http://avatechsupport.blogspot.se/2008/03/how-to-set-3gb-startup-switch-in.html How to set the /3GB Startup Switch in Windows XP and Vista]".

Lebarhon at 08:23, 14 September 2015

2015-09-14T08:23:36Z

New page

[[Category:General]]
RawTherapee 4 does all calculations in precise 32-bit [https://en.wikipedia.org/wiki/Floating_point floating point] notation (in contrast to 16-bit integer as used in many other converters like [https://en.wikipedia.org/wiki/Dcraw dcraw] and also in RawTherapee up to version 3.0) so nothing gets rounded off and lost.

Classical converters work with 16-bit integer numbers. A pixel channel has values ranging from 0-65535 in 16-bit (to increase precision converters usually multiply the 12-14 bit camera values to fill the 16-bit range). The numbers have no fractions, so for example there is no value between 102 and 103. In contrast, floating point numbers store a value at a far wider range with a precision of 6-7 significant digits. This helps especially in the highlights, where higher ranges can be recovered. It allows intermediate results in the processing chain to over- or undershoot temporarily without losing information. The fraction values possible also help to smooth color transitions to prevent color banding. And not the least, floating point makes the life easier for developers which don't need to worry as much about rounding errors or clipping when developing image algorithms for RawTherapee.

The downside is the RAM space floating point numbers require, which is exactly twice that of 16-bit integer. Together with the ever-increasing megapixel count of digital cameras a 32-bit operating system can quite easily run out of memory and cause RawTherapee to crash. Therefore a 64-bit operating system is highly advised for stability. If you have problems running RT on a 32-bit system, try the following:

* As a general rule, you should avoid having folders with too many raw photos in them as each photo takes up memory when displayed in RawTherapee's File Browser tab. Try not to have more than 100 photos per folder.
* RawTherapee uses more RAM while you are using the File Browser tab, so avoid opening that tab while you are processing photos.
* Use 4-Gigabyte Tuning in Windows. See "[http://msdn.microsoft.com/en-us/library/bb613473%28VS.85%29.aspx 4-Gigabyte Tuning: BCDEdit and Boot.ini]" for an explanation of what it is, and find out how to do it by reading the guide "[http://avatechsupport.blogspot.se/2008/03/how-to-set-3gb-startup-switch-in.html How to set the /3GB Startup Switch in Windows XP and Vista]".
* Close other programs while working in RawTherapee.
* Close the Image Editor tab when you're done editing to free up memory.
* Turn off "auto-start" in the batch queue. Only add photos to the batch queue once you are done editing all of them, and then start it. Use the batch queue, do not use the immediate save button.
* Change to a directory with few or no photos in it before starting the batch queue.
* You can free some memory by deleting (or moving to a different folder, or renaming to something like .unusedicc) all the .icc profiles in iccprofiles\input for the cameras you do not use.
* Assure that the Dark-frames Directory and the Flat-fields Directory in Preferences do not point to folders containing raw-files if you do not use Dark-frames or Flat-fields.
* The most memory-intensive tools are [[Tone Mapping]], [[Contrast by Detail Levels]] and [[Exposure#Highlight_Reconstruction | Highlight Reconstruction]] using "Color Propagation", so you might need to avoid using them if your machine and operating system are not up to standard.