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Topic: Downsampling

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	Downsampling High Resolution photography scans for use in image databases
		The whole reason for "downsampling" is to create an "access" image that is a miniaturized duplicate of your optical resolution "master" scan.
		Downsample from 350 to 247ppi, again the file size should be about half of what it was before.
		Downsample from 220 to 150ppi, again the file size should be about half of what it was before.
	www.controlledvocabulary.com /imagedatabases/downsampling.html (2008 words)

	Downsampling
		Average Downsampling is to average the pixels in a sample area and then substitute the entire area with the average pixel color at the specified resolution.
		Bicubic Downsampling is to use a weighted average to decide pixel color.
		Bicubic Downsampling is the most precise method, but it takes time to yield the smoothest tonal gradations.
	www.pdflogic.com /chm/ImageProcessing.html (358 words)

	Digital simulation model for forward looking infrared (FLIR) sensors - Patent 5043930
		The optics are also positioned prior to the detector downsampling to avoid aliasing of the input scene signal since the optics have a finite bandwidth which is a much wider bandwidth than the detectors.
		The detector downsampling of the optics output scene map 32 in the spatial domain by operation 34 produces a scene map 36 in the spatial domain.
		The inventive concept is comprised of a digital nonrecursive system in which optics are placed prior to downsampling and that a MTF effect, such as optics, can be applied to a set of digital data, i.e., the input scene data on map 10, without transferring the data into the frequency domain.
	www.freepatentsonline.com /5043930.html (2580 words)

	[No title]
		Based on the operation selected, smoothing or downsampling, your system should perform the operation and output a sequence of integer values which represent the audio signal after processing.
		The downsampling factor M is the ratio between the old and new frequencies.
		To achieve a downsampling factor of 4 we would drop 3 samples for every 4 in the input stream.
	www.ics.uci.edu /~harris/cs153/psets/probset6.txt (431 words)

	Process
		This is done in terms of ratios which usually take the forms 4:4:4, 4:2:2, and 4:2:0, with the left number referring to the number of the luma (Y) samples, the middle number referring to the number of Cb chroma samples, and the last number referring to the number of Cr chroma samples.
		A 4:4:4 ratio represents no downsampling, a 4:2:2 represents downsampling by a factor of two in the horizontal direction, and a 4:2:0 represents downsampling by a factor or two in both the horizontal and vertical direction.
		Downsampling/chroma subsampling allows the number of bytes per pixel pair to be reduced, specifically by the sampling ratio [6].
	www.amherst.edu /~rgrammer08/process.html (767 words)

	bit-tech.net \| PowerDVD audio downsampling explained
		This didn't really clear up the downsampling situation though because, as far as we're aware all audio, regardless of encryption, is downsampled.
		Regardless of the no protection downsampling "bug" that currently exists in PowerDVD Ultra, it seems that those who have pushed AACS on us are progressively killing the home theatre PC industry.
		The confirmation of the "bug" that downsamples all high res content indiscriminately is rather concerning given how much they tout their audio support in their marketing.
	www.bit-tech.net /news/2007/10/08/powerdvd_ultra_audio_downsampling_explained/1 (1351 words)

	Multirate DSP, part 2: Noninteger sampling factors \| Programmable Logic DesignLine
		Part 1 explains how to upsample and downsample by an integer factor.
		With an understanding of the downsampling and upsampling processes, we now study the sampling rate conversion by a non-integer factor of L/M.
		Downsampling by a factor of M = 8.
	www.pldesignline.com /howto/207403053 (865 words)

	How to Create PDF Files Free from 300+ File Types - PrimoPDF Support
		Downsampling is used to help reduce the size of your outputted PDF file.
		Downsampling reduces an image's resolution (to the resolution specified) by discarding pixels.
		When bicubic downsampling is applied, PrimoPDF uses bicubic interpolation to generate new pixel values.
	www.primopdf.com /primopdf_support_manual.aspx (2656 words)

	Downsampling
		After all there is some change in quality when you have to downsample so you also have to consider if the gain in quality you got on the tracks is going to make it through that.
		In a nutshell without getting technical with you, dithering assists with proper downsampling and allows the file to keep its original sound as it is downsampled to a lower bit and sample rate.
		What I was told to do was downsample prior to mixing so I could use the UAD stuff when mixing without much issue.
	forum.cakewalk.com /tm.asp?m=1432217 (1513 words)

	Photoshop CS3 * Compression and downsampling options for Adobe PDF
		Depending on the settings you choose, compression and downsampling can significantly reduce the size of a PDF file with little or no loss of detail and precision.
		Average downsampling is the same as Bilinear resampling.
		Subsampling significantly reduces the conversion time compared with downsampling but results in images that are less smooth and continuous.
	livedocs.adobe.com /en_US/Photoshop/10.0/WS4DE92D2D-5A4C-42a8-90E1-FD4E912A9BFD.html (634 words)

	Multirate DSP, part 1: Upsampling and downsampling \| Mobile Handset DesignLine
		The process of reducing a sampling rate by an integer factor is referred to as downsampling of a data sequence.We also refer to downsampling as ''decimation'' (not taking one of ten).
		and we downsample the data sequence by a factor of 3, we obtain the downsampled sequence as
		From the Nyquist sampling theorem, it is known that aliasing can occur in the downsampled signal due to the reduced sampling rate.
	www.mobilehandsetdesignline.com /howto/207401023 (889 words)

	Image Compression : JPEG with Emphasis on "Baseline" Lossy JPEG, Progressive & Motion-JPEG (Site not responding. Last check: )
		Note that this step is not compulsory as the JPEG algorithm actually works on each independent component and doesn't care what data it is. But this step does increase the compression ratio as it removes unnecessary information in the chrominance components without the human eye detecting the difference.
		It is done by dividing the pixels of each components into groups and for each group we find their average value, and use only one pixel of that average value to represent that whole group.
		Downsampling is done only to the chrominance components, often reducing them by half horizontally and half vertically or no change for the vertical.
	pascalzone.amirmelamed.co.il /Graphics/JPEG/JPEG.htm (7228 words)

	Developing for Developers : How does JPEG actually work?
		A different approach is instead of downsampling the entire image, to only downscale certain channels of the image.
		The results are visually obvious: we are sensitive to red and green, but even more sensitive to intensity or luminance, the relative brightness of pixels compared to other nearby pixels.
		For this reason, typical JPEG files convert images to the YCbCr color space, and then downsample both the Cb and Cr channels by a factor of 2 in both width and height.
	blogs.msdn.com /devdev/archive/2006/04/12/575384.aspx (1836 words)

	TurboIIS HTTP Compression and JPEG Downsampling for Internet Information Services (IIS)
		If that level is not appropriate for certain images on your site, you can tell it to use a different level of downsampling, just for those images.
		This is convenient when you have certain images that are important to keep at high quality, such as a logo, or certain larger images that normally take a long time to download and don't need to be at full quality.
		Downsampling is a lossy method of compressing images.
	www.turboiis.com /downsampling.asp (217 words)

	downsampling [ AudioMasters Forums - The Home of the Original Cool Edit and Adobe Audition Community ]
		However, a quality setting of 999 in AA1.0 and later is the same as 500 in CEP2.1; using the 999 level in CEP2.1 yields the most accurate anti-aliasing known to humanity (pre/post filter set to OFF - you don't need it at that level).
		But tonight I ran a related test that Ozpeter suggested to me a month ago: I recorded jingling car keys at different rates and compared them (first recording at 32/44.1 and second recording at 32/96).
		Then I downsampled the higher rate and compared it to the orginal, and again I couldn't hear any difference.
	www.audiomastersforum.net /amforum/index.php?topic=6654.msg64243 (904 words)

	Downsampling
		Options on this window are used to configure downsampling for monochrome images, indexed images and high color images.
		That means the images will be added in the PDF file at a different resolution then the one from the original document.
		By default, the Bicubic downsampling method is used to downsample images to the selected resolution.
	www.novapdf.com /templates/online-help/downsampling.htm (121 words)

	Downsampling - Gearslutz.com
		I told him simply because I use UAD plugs a lot and using a higher sampling rate would be too much of a headache.
		He told me to record at a higher sampling rate and downsample when it comes time to mix.
		especially if tracking at 96 and downsampling to 44.1, 88.2 to 44.1 would be better.
	www.gearslutz.com /board/music-computers/246631-downsampling.html (198 words)

	Create Adobe PDF Online - Compression Settings Help
		The default setting for monochrome is CCIT Group 4 compression and no downsampling.
		The downsampling alternatives are 300, 150, and 72 dpi.
		Downsampling reduces file size by reducing the spatial resolution (pixels per inch) of the image.
	createpdf.adobe.com /cgi-feeder.pl/pchelp_compression?BP=&LOC=en_US (208 words)

	Multirate FAQ: Decimation
		"Downsampling" is a more specific term which refers to just the process of throwing away samples, without the lowpass filtering operation.
		A signal can be downsampled (without doing any filtering) whenever it is "oversampled", that is, when a sampling rate was used that was greater than the Nyquist criteria required.
		But in the more common case of decimating (combining filtering and downsampling), the computational and memory requirements of the filters can usually be reduced by using multiple stages.
	www.dspguru.com /info/faqs/multrate/decim.htm (1632 words)

	Scanning: Downsampling to reduce grain? - Photo.net Digital Darkroom Forum
		I've read somewhere that scanning at the highest resolution (in my case 4000ppi with a Nikon 9000) and then later downsampling to ca.
		So unless you are short of disk space, it makes no sense to scan at less than 4000ppi, since it throws away information that you might find useful later.
		FWIW if as has been suggested downsampling is loosing detail, then defocusing your scanner is gonna do that too.
	photo.net /digital-darkroom-forum/00MjIY (896 words)

	Resolution
		Downsampling: In the example below, reducing the number of pixels per inch from 320 to 10, the image becomes very pixelated.
		However, from 600 dpi to 400 dpi, as shown below, you aren't likely to see a difference, because our best printer has a limit of 400 dpi.
		The benefit of downsampling is that you get a much smaller file size that is easier to store and work with.
	jura.wi.mit.edu /bio/graphics/scanning/resolution.htm (857 words)

	Ampache / Downsampling Woes with Linux
		I adjusted the downsample command to include full paths for mp3splt and lame, same error.
		I've had no trouble getting downsampling to work in 3.3.3.3 These are most likely configuration issues.
		Make sure that the command that is run (as displayed in the log) when run as the user that the webserver runs as, actually works and is a playable file.
	ampache.org /forums/viewtopic.php?pid=7343 (324 words)

	Correct hdr downsampling with fragment shader and texturefilter - OpenGL.org Discussion and Help Forums
		I downsample the scene to a 1/4 of its size with an extra shader which reads and averages a 4x4 box of texels.
		The interpolated texture coordinate would then be offset by approximately 0.5*texel in the fragment shader.
		The ortho matrix and the vertex coordinates for pixel operations need to be exactly on the pixel's corners, so that the texture coordinate interpolation inside the fragment pipeline takes care to hit the centers of the texels in a 1-to-1 mapping.
	www.opengl.org /discussion_boards/ubbthreads.php?ubb=showflat&Number=189748 (980 words)

	Downsampling and Aliasing
		The aliasing theorem states that downsampling in time corresponds to aliasing in the frequency domain:
		The frequency scaling corresponds to having a sampling inverval of
		The aliasing theorem makes it clear that, in order to downsample by factor
	ccrma.stanford.edu /~jos/sasp/Downsampling_Aliasing.html (139 words)

	Downsampling to an ipod \| Ask Metafilter
		Right now I'm still using my trusty 4Gb Ipod mini so I like to downsample my mp3's from 320kbs/lossless to 160kbs so that I can get a few extra albums on.
		I don't believe Itunes or Winamp has a plug-in to allow downsampling during transfers but I might not have looked hard enough.
		it lets me downsample my mp3s and convert flac/wav/whatever to mp3s with the appropriate dlls installed.
	ask.metafilter.com /89485/Downsampling-to-an-ipod (403 words)

	[No title]
		This ties the I/O thorn to the driver since it needs to know about data distribution, ghostzones, etc. A clean way of separating the I/O code from the driver is to use a thorn which provides a generic interface to extract the distributed data and return it to the I/O processor.
		The downsampling parameter denotes the downsampling factors for the hyperslab to be extracted.
		The resulting size of the hyperslab to be extracted is set according to the hyperslab extents and downsampling parameters chosen.
	www.cactuscode.org /old/Development/Specs/Hyperslab.txt (1465 words)

	LTI-Lib: lti::downsampling Class Reference
		The downsampling::parameters specify which kind of filter should be used and which downsampling factor.
		lti::downsampling downsampler; // downsampling functor lti::downsampling::parameters param; // downsampling parameters // a gaussian kernel to use before the downsampling lti::gaussKernel2D gkernel; param.
		downsample a color image by splitting it into the RGB components, downsampling each channel and merging the results
	www.eml.hiroshima-u.ac.jp /member/staff/tamaki/ltilib/doc/classlti_1_1downsampling.html (251 words)

	Web Presenter Pro Plugin
		Choose from any pixel dimension or even downsample your images by scale by using smart algorithms.
		The new interface functionality and concept was based on the feedback from many photographers looking for the highest quality when downsampling their files and presenting them on the web, monitor or projector.
		The WP Pro plugin is the next generation downsampling tool and it's part of the FM Essential Digital Darkroom plugins.
	www.fredmiranda.com /WP_Pro_Plugin (400 words)

	Downsampling Operator
		The stretch and downsampling operations do not commute because they are linear time-varying operators.
		Note that the term ``downsampling'' may also refer to the more elaborate process of sampling-rate conversion to a lower sampling rate, in which a signal's sampling rate is lowered by resampling using bandlimited interpolation.
		To distinguish these cases, we can call this bandlimited downsampling, because a lowpass-filter is needed, in general, prior to downsampling so that aliasing is avoided.
	www.dsprelated.com /dspbooks/mdft/Downsampling_Operator.html (263 words)

	[magick-users] problem downsampling -> convert -density
		Previous message: [magick-users] problem downsampling -> convert -density
		At 01:18 PM 5/22/02 +0200, Peter Vanroose wrote: >> I would like to downsample pictures (tiff, jpeg) from 300dpi to 72dpi but can't get it to work.
		However, if you are using PhotoShop to determine what is the resolution of the output image, be aware that PhotoShop ignores the standard resolution tag and uses its own instead, which is embedded somewhere in one of the "profiles" and does not get updated by ImageMagick.
	studio.imagemagick.org /pipermail/magick-users/2002-May/002779.html (459 words)

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