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loock
Rookie User
Inregistrat: acum 12 ani
Postari: 3
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In primul rand, scopul si subiectul thredului era lucru in Premier, probabil editare.
Chiar daca am ajuns sa discutam despre placi grafice, OpenCL vs CUDA vs QuickSync, totusi nu transcodingul era subiectul.
Chiar si asa, AMD sta incompabil mai bine fata de CUDA, atat la viteza ( seria HD 7xxx only), deci nu atat 7970/7950, dar si 7870 sau 7850, de pana la 3 X mai rapid decat CUDA, in functie de software.
cat si la calitatea imaginii, care in multe aplicatii este catastrofal mai buna fata de ce scoate CUDA.
Da, depinde mult de software, si la unele ar fi cazul sa fie facute niste reglaje custom, deoarece fiecare sistem trateaza diferit.
Da, in functie de aplicatia software, AMD aplica in general mai mult sharpening ( exact pe dos decat mushy), ceva mai contrast, poate si levels si vibrance mai mult, si asta inseamna nu doar o imagine mai sharp, dar din pacate si ceva pierderi de detalii in umbre, sau lumini mai arse.
Dar repet, depinde de software si de setarile particulare facute ( care difera la fiecare din cele 4 - CPU software, QuickSync, CUDA si OpenCL AMD), si pe anumite programe, AMD nu mai are acele pierderi in umbre si lumini, si reda asemanator cu originalul sau putin mai sharp.
In general, QuickSync este OK, setat de intel sa redea cat mai aproape de varianta software clasica, insa fiind totusi o cale complet diferita, nu are cum sa fie identica, si uneiori se intampla sa redea foarte nasol !
Vezi jos la pagiona 3, continuare la Cyberlink Media Espresso 6.5, din testul la care duce ultimul link de la AlexIP:
"The square, blocky smoke from Quick Sync is a nice touch. Because normal gaseous behavior is so 19th century."...
La pagina 5, Arcsoft Media Converter, cel care este la pagina 6 din link-ul pus de AlexIP citez :
- "Apart from the resizing, the difference between Radeon, Quick Sync, and the original file is minimal. The Radeon’s output is very slightly sharper, but that’s all."
- "Again, the difference between all three is very small. The Radeon 7950 gives the best image by a whisker, but Quick Sync is very, very good here "
La pagina 6, da, cu acelasi Arcsoft MC, pe AMD se pierd detalii in umbre si lumini, dar este incompatibil cu...CUDA...
Alt test ceva mai vechi, facut pe Seria HD 6xxx care este mult mai lenta decat seria HD 7xxx, aici
Testul arata ca, QS este in general f. bun, rapid si f. apropiat de varianta software, dar arata si ca varianta CUDA este catastrofal mai proasta !!!
“Wow... there are some serious differences in quality. I'm concerned that the 1.mp4 is the accelerated transcode, in which case it looks like poop..”
“Video 1: Lots of distracting small compression blocks, as if the grid was determined pre-encoding (I know that generally there are blocks, but here the edges seem to persist constantly). Persistent artifacts after black. Quality not too amazing, I wouldn't be happy with this.”
Video one, which many assumed was Quick Sync, actually came from the GeForce GTX 460. The CUDA codepath, although extremely fast, actually produces a much worse image. Videos 2 and 3 were outputs from Sandy Bridge, and the editors generally didn’t agree on which one of those two looked better just that they were definitely better than the first video.
Este mai jos redata si o scena dinamica, de la o terasa, cu 4 variante de redare:
x86 pe i5 2500K, Intel QuickSync, NVidia GTX 460, si AMD HD6870
Imaginea redata de GTX 460 arata plina de zgomot de imagine, fata de toate celelalte.
"Comparing the shots above the only real outlier is NVIDIA’s GeForce GTX 460. The CUDA path clearly errs on the side of performance vs. quality and produces a far noisier image. The ATI Stream codepath produces an image that’s very close to the standard x86 and Quick Sync output. In fact, everything but the GTX 460 does well here."
Mai jos inca o scena dinamica cu mers peste acoperisuri cu tigle.
"The image quality story is about the same for AMD’s GPUs and the x86 path, however Quick Sync delivers a noticeably worse quality image. It’s no where near as bad as the GTX 460, but it’s just not as sharp as what you get from the software or ATI Stream codepaths."
Mai jos, inca un exemplu cu o masina in mers si foc:
"The GeForce GTX 460 looks horrible here. The output looks like an old film, it’s simply inexcusable.
The Radeon HD 6870 produces a frame that has similar sharpness to the x86 codepath, but with muted colors. Quick Sync maintains color fidelity but loses the sharpness of the x86 path, similar to what we saw in the previous test. In this case the loss of sharpness does help smooth out some aliasing in the paint on the police car but otherwise is undesirable."
Toata treaba difera mult in f. de software si de setari.
In unele, AMD reda cu vibrance mai mare si sharpening mai mult, tone/levels mai agresiv, iar in altele este chiar invers, culori mai "muted", deci depinde clar de setari !
Reamintesc din nou, seria HD 7xxx este mult mai rapida la compute performance fata seria HD 6xxx, deci quickSync nu mai are avantajul vitezei, iar CUDA nici atat...
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aș căuta pe cineva care și-a luat un i7 face upgrade sau și și-a dat seama că e prea mult / prea scump / prea neportabil pentru el.