Background...
While all 3 companies, AMD/ATI, Nvidia, & Intel can handle OpenCL, they also have their own proprietary methods for speeding up video processing. This stuff works similarly to Direct X -- rather than write however many lines of code developers can make much simpler calls to built-in functions that do the same things, & that speeds everything up. OpenCL **May** be the way of the future, but only time will tell -- AMD/ATI does OpenCL better than Nvidia when you compare their current lineup, so it might make sense for Nvidia to push their CUDA instead... Nvidia's next chip may hint at what to expect. And along with OpenCL & whatever proprietary tech graphics hardware can use, there's the older DXVA [Direct X Video Acceleration] which can play a big part increasing video processing speed, especially with older formats like mpg2.
Now, AMD & Nvidia make GPUs, while Intel puts their GPU on die with some of their CPUs. With AMD & Nvidia how much video assist you get depends on how much you spent on their graphics hardware -- with Intel not so much. OpenCL is fairly new, & apps using it are rare, while Nvidia's CUDA is the most widespread in use, followed by AMD's Stream or Avivo, which they *may* be phasing out [parts of their Stream tech were removed when AMD released their 1st win8 driver set]. Intel's Quick Sync is the fasted of all these methods [OpenCL, CUDA etc.], but it's the least common in use, and if you use an add-on graphics card it can be tricky, may require something like Virtu [built into some motherboards] before you can use Quick Sync at all.
Here's what all this means to you...
If your PC/laptop uses the graphics built into an Intel CPU for display, video converters, rippers & such *May* become an awful lot faster for you. If you use AMD/ATI or Nvidia graphics hardware, if you've got an Intel CPU with built-in graphics, & If your motherboard can access that on-board GPU [i.e. your motherboard has graphics ports, e.g. HDMI], you *might* be able to use Quick Sync to speed things up too. On the down side installing one of these newer apps *may* effect the way Windows handles video, installation *may* add a bit to registry bloat, & some of these newer video apps may just not work for you, at all.
Intel does have an SDK for this stuff, & apps like Blaze Video DVD Copy & Aviosoft Video Converter Pro include portions of that Intel code, that in win7 64 adds loads & loads of registry entries, & when tested on this rig with an AMD 7870 & i7 2600K CPU on a board with Virtu it didn't work. The GOTD Aunsoft DVD Ripper OTOH only uses Quick Sync that's embedded into ffmpeg -- a guy working for Intel wrote code for Quick Sync on his own time that's included in ffdshow, LAVFilters, & ffmpeg etc. -- that you enable for *decoding only* in the app's preferences or options... that works, but I'd expect much more benefit if/when the source was AVC/H.264 rather than DVD mpg2.
If you're the type that's concerned about needless registry bloat, &/or if you're careful about what video related apps you add, install 1st to a VM, or use something like Time Freeze, or use 7-zip or Universal Extractor to see if you can unpack the setup file -- the 2 apps I mentioned with parts of the Intel SDK very clearly had an Intel sub folder.