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Compute Shaders: Optimize your engine using compute / Lou Kramer, AMD - YouTube
Good overview of how compute shaders work, uniform/non-uniform variables, local data store (LDS) etc etc

example on how to optimize a downsample
ComputeShader  optimization  overview  intrinsics  downsample 
november 2018 by MemoryStomp
MSAA-based Coarse Shading
Maintaining real-time frame rates at the native resolution of high pixel-density displays is very challenging, especially on power-constrained mobile devices. For this reason, many applications render at a lower resolution and upscale the results. Decoupled sampling approaches offer a better solution to this problem, by sampling the visibility at a higher rate than shading, thus preserving the clarity of geometric edges, while reducing the cost of shading. However, this ability is rather limited in current graphics architectures, where the widely-used MSAA algorithm shades each covered primitive at least once per pixel, without directly providing the ability to compute pixel shading at a more coarse rate. While various extensions of the graphics pipeline for coarse shading have been proposed, in this work we focus on a software implementation for existing GPUs. To this end, we render an intermediate render buffer at a lower pixel count, but at the same time we compensate the loss in resolution by adding the appropriate amount of MSAA sub-pixel samples, in order to guarantee at least one visibility sample per display pixel. Subsequently, a custom resolve shader is used to perform the mapping of sub-pixel MSAA samples to pixels. This simple technique effectively shades more coarsely pixel blocks, where there are no geometric edges. We demonstrate our method on several test scenes with varying degrees of geometric and shading complexity and our measurements indicate an up to 45% reduction in energy consumption.
MSAA  Downsample  VFX  optimization 
november 2017 by MemoryStomp
Rendering of Call of Duty: Infinite Warfare - Activision Community
"Multi-resolution" vfx sounds great. Last-gen trick (MSAA alias of the full screen) updated so it still works.
DigitalDragons  EngineOverview  vfx  vfxLighting  VolumetricFog  volumetric  LightProbes  downsample 
july 2017 by MemoryStomp
Reduce existing MP3 bit rate in iTunes - Mac OS X Hints []
In German, it's Ablage -> Neue Version erstellen -> MP3-Version erstellen.

It's simple, just set the bit rate you want in iTunes' preferences, and select the songs you want to down sample. Then under the Advanced menu, select "Convert Selection to MP3." Thats it! Done (after you trash the high bit-rate songs of course). I can now fit many more songs on my iPod!
itunes  mac  osx  mp3  bitrate  downsample  samplerate  tipsandtricks  solution 
july 2016 by kme
Applied Graphics Research for Video Games
Natalya Tatarchuk

research, R&D, constraints, edge cases

case studies:
particle downsampling (is this an update on the vfx downsampling case, or the same thing?)
graphics  research  vfx  downsample  atmosphere 
june 2015 by MemoryStomp
iPad 101: The easy way to get high-def videos onto iPhone or iPad
Filed under: iTunes, iPad
Even though the iPad has that HD feel, there are plenty of HD files it can't stomach -- the maximum resolution for videos to sync via iTunes is 720p, and anything higher (1080i or 1080p) simply won't transfer. On the iPhone and iPod touch, the upper limit is even tighter; those devices can only handle 640x480 videos, meaning that a 720p file will stall out. Generally, movies or TV shows purchased from iTunes will arrive with versions tuned for both devices, but for anything you've created independently of the store, you may run into a spot of trouble.

There's an extensive walkthrough over at Gizmodo covering how to use Handbrake for downsampling your 1080i/p videos to a more manageable resolution, very helpful if you're in a DIY mood -- but there is an easier way. It takes advantage of a feature in an app you're already using: iTunes.

Just select your movie file(s) and check under the Advanced menu. See those two "Create..." options? The iPod or iPhone version will deliver a resampled video at a resolution the smaller devices can manage; the iPad/Apple TV choice will spit out a 720p file. All you need to do is select your choice and wait for a while... depending on the length of your video and the speed of your Mac, it may take quite a long time, but be patient. You can try out the steps with an Apple-provided sample file, if you like.

Once the conversion is done, you'll see a second instance of the video in your media list -- then you can sync at will. Note that if the file you're choosing is already adequately low-res, you'll see the dialog box below.

Happy squeezing!
TUAWiPad 101: The easy way to get high-def videos onto iPhone or iPad originally appeared on The Unofficial Apple Weblog (TUAW) on Wed, 07 Apr 2010 14:00:00 EST. Please see our terms for use of feeds.
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101  downsample  handbrake  hd  ipad  ipad_101  ipad-101  Ipad101  iphone  video  from google
april 2010 by knilob

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