joema Posted December 22, 2015 Share Posted December 22, 2015 This is completely false, using a GPU with CUDA takes the playback away from the CPU and puts it on the GPU. Most modern GPU have hardware H264 decode.This is especially the case with H265 from the NX1 with the GTX960, as it uses the onboard H265 decoder on the card for playback.The OP himself quoted his performance numbers during playback: "...CPU usage and GPU usage while scrubbing my CPU maxes out to 100% on all four cores but my GPU stays under 10%" The reason he observed this is because the nVidia GPU could not assist with playback.It is impossible for a traditional GPU to substantially accelerate H264 encode/decode. The algorithm cannot be productively parallelized to harness the GPU. Andrew Page (nVidia Product Manager for Professional Video Technologies), explained this in a recent interview: "there are a lot of tasks that can't be broken down to be parallel: encoding is one, decoding some of the camera compressed formats is another one...what happens in frame 2 depends on frame 1, we do something to frame 1 then feed the results into frame 2....that's pretty much an encoding problem...everything is interrelated, so we can't break it up into lots of different simultaneous things." (That Studio Show podcast, 5/20/14: https://itunes.apple.com/us/podcast/that-studio-show/id293692362?mt=2) The lead X264 developer Jason Garrett-Glaser explained how all previous attempts to meaningfully use GPU acceleration on H264 have failed: "...Incredibly difficult...countless people have failed over the years. nVidia engineers, Intel engineers...have all failed....Existing GPU encoders typically have worse compression...and despite the power of the GPU, still slower....The main problem is [H264] video encoding is an inherently linear process. The only way to make it not linear is using different algorithms [which entail] significant sacrifices." (https://www.youtube.com/watch?v=uOOOTqqI18A)Because of the GPU's inability to accelerate long-GOP codecs like H264, both nVidia and AMD have been forced to add separate fixed-function logic and APIs to access these, separate and distinct from the GPU and its APIs. nVidia's is called NVENC and AMD's is called VCE (Video Coding Engine). These are integrated on some higher-end video cards but architecturally these are a "bag hung on the side" and have nothing to do with CUDA or OpenCL.This is roughly similar to Intel's Quick Sync hardware encode/decode logic, on most Intel CPUs since Sandy Bridge. Starting with Skylake Quick Sync can handle H265. While FCPX has used Quick Sync for years, Premiere does not.The fact that a few video cards have adopted non-GPU logic and separate APIs to accelerate video encode/decode does not change the fact that a traditional GPU (meaning most in the current installed user base) cannot significantly help this task. Garrett-Glaser made very clear in his tech talk that the additional encode logic has nothing to do with the GPU. If you have a new-generation video card with separate video encode/decode logic, and if your software is specifically written to those non-GPU APIs, it may accelerate long-GOP encode/decode. But that is not the GPU doing the work, and it's not done via the CUDA or OpenCL APIs. In the case of Premiere this means the very latest version of Premiere Pro CC, 2015.1, released two weeks ago. Note this feature is not in the evaluation version of Premiere, to evaluate the H265 feature you must purchase (ie subscribe) to CC. Quote Link to comment Share on other sites More sharing options...
gethin Posted December 22, 2015 Share Posted December 22, 2015 seeing as you can use the graphics card in any new system you decide to get, i'd say this was a no-brainer upgrade Geoff CB 1 Quote Link to comment Share on other sites More sharing options...
MountneerMan Posted December 23, 2015 Author Share Posted December 23, 2015 The OP himself quoted his performance numbers during playback: "...CPU usage and GPU usage while scrubbing my CPU maxes out to 100% on all four cores but my GPU stays under 10%" The reason he observed this is because the nVidia GPU could not assist with playback. I currently don't have an nvidia GPU, I have an AMD R7. In either case your point still holds up and I dont think upgrading my video card will help with playback of h.264 or h.265 files. Transcoding seams to be the only way to go as I can playback ProRes LT files smooth as eggnog (a little topical humor). seeing as you can use the graphics card in any new system you decide to get, i'd say this was a no-brainer upgrade However I do think the GPU will help with the dropped frames that I am seeing when I add effects to a clip. This lead me to do some more research and now I have a much worse problem that I don't think anyone here can help me with.A GTX 960 (or pretty much any video card worth getting for that matter) is going to require me to upgrade my power supply witch I was pretty sure was the case going into this but was ok with it because I would be able to reuse the PSU in a new computer in a few years. The problem is my computer is an HP and the PSU/motherboard has proprietary connectors :') I think I might be able to barely squeeze by with a GTX 960 if I get cable connectors to convert the two optical drive cables to an 8pin video card connector. What do you guys think lol It is also worth mentioning again that I got this computer for free about a year and a half ago and so I dont want no crap about buying an HP. lol Quote Link to comment Share on other sites More sharing options...
Don Kotlos Posted December 23, 2015 Share Posted December 23, 2015 I think I might be able to barely squeeze by with a GTX 960 if I get cable connectors to convert the two optical drive cables to an 8pin video card connector. What do you guys think lol it will work fine as long as the current threshold of the Sata power is not met.Worst case you will get a crash and know that you need a new case and psu. Geoff CB 1 Quote Link to comment Share on other sites More sharing options...
joema Posted December 23, 2015 Share Posted December 23, 2015 I currently don't have an nvidia GPU, I have an AMD R7. In either case your point still holds up and I dont think upgrading my video card will help with playback of h.264 or h.265 files. Transcoding seams to be the only way to go as I can playback ProRes LT files smooth as eggnog (a little topical humor). Just to be clear, if you are on the latest Premiere CC and you have a subscription and you can afford a GTX-960 and your power supply can run it -- it is possible it could help with H264 and H265. This is not the GPU per se, it is not accessed via the CUDA API, rather it is special logic on that card that Premiere can utilize via NVENC -- as of two weeks ago. It would not hurt to try this. Geoff CB 1 Quote Link to comment Share on other sites More sharing options...
MountneerMan Posted December 23, 2015 Author Share Posted December 23, 2015 it will work fine as long as the current threshold of the Sata power is not met.Worst case you will get a crash and know that you need a new case and psu. The case would fit a new PSU. Its the motherboard that has proprietary connectors that no other PSU has My power supply is rather for 320 watts and when I calculate my power usage with an online calculator it says my total load is 320 watts so it should just sqweek by. The second issue is I would need to get an adapter to use the SATA power cables to plug into the 8 pin power cable on the GTX 960. any one ever do this before? Quote Link to comment Share on other sites More sharing options...
Don Kotlos Posted December 23, 2015 Share Posted December 23, 2015 The case would fit a new PSU. Its the motherboard that has proprietary connectors that no other PSU has OK so in the worst case you will have to buy a new system . Jokes aside you should be prepared for this before you go on squeezing the max out of your system. My power supply is rather for 320 watts and when I calculate my power usage with an online calculator it says my total load is 320 watts so it should just sqweek by. The second issue is I would need to get an adapter to use the SATA power cables to plug into the 8 pin power cable on the GTX 960. any one ever do this before? Yeah I have done it multiple times. Here is one cable that should work:http://www.amazon.com/Branded-8inch-15pin-Express-Power/dp/B005NJXY7OThe total load is rarely met. Its good to have a PSU that is above that but not necessary. The gtx960 if not overclocked should be about 120W and your CPU 95W. These numbers are achieved continuously only with programs such as prime95 and futuremark. With video editing the maximum load usually happens during rendering and then CPU and GPU rarely max out simultaneously and when they do its only for brief moments. Quote Link to comment Share on other sites More sharing options...
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