Sadly, the ability to grab a snapshot of the background is gone – instead, only a background colour can be defined – but it still gave excellent results.
A new chroma-keying tool, called Ultra Key, is essentially the guts of Adobe Ultra, a stand-alone application that was bundled with Premiere Pro CS3. There’s native support for various professional camera formats such as AVC-Intra. The Mercury Playback Engine is such an important new feature that it’s perfectly acceptable that there are only a few others.
We were testing with Beta code, though – and we’ll update this review when the final code is available. It seems that the software isn’t ideally written to share the load between the graphics and central processors. Motion, blend modes and opacity are also accelerated, but we found that highly complex timelines caused Premiere Pro to crash when CUDA was enabled. There are 30 other effects that benefit from CUDA acceleration, and they’re clearly marked in the library. Without the card, our PC dropped frames with just one instance of this effect.
We had a chance to try the £1,500 Quadro FX 4800, which managed 14 instances of the demanding Three-Way Color Corrector effect at the full 1080p resolution. Sadly, the list of supported cards is currently limited to the GeForce GTX 285, which costs £250, and various Quadro models with prices from £600. The software uses Nvidia’s CUDA architecture to access the graphics processor, which has lots of parallel cores that are well suited to video-editing tasks. However, fitting our test PC with a suitable nVidia graphics card gave a dramatic boost to effects performance. We didn’t immediately see such dramatic improvements in Premiere Pro’s ability to preview effects in real time. This ability to balance preview detail and smoothness is extremely welcome, but we’d like a readout that clearly shows when frames are being dropped. Selecting full resolution meant both Adobe and Sony’s editors only managed four AVCHD streams. To achieve the above figures, we set playback to half resolution (960x520), which is usually plenty for accurate edits. Part of the reason for CS5’s superb performance is a new feature that lets users define the preview resolution – something Vegas Pro has offered for years, incidentally.
Our PC used to test CS5 would cost around £1,000, so 70 per cent of the performance for a fifth the price seems pretty good value. Apple Final Cut Pro doesn’t support Windows, but in tests on a £5,000 top-spec Mac Pro, it managed 14 streams after transcoding to a friendlier format. Sony Vegas Pro 64-bit managed five streams on the same PC. It managed 10 simultaneous 1080i AVCHD streams – an extremely demanding format to decode. We tested on a Windows 7 64-bit PC fitted with a Core i7 processor and 8GB RAM, and were blown away by its preview performance.
The software now supports 64-bit operating systems only (and drops Windows XP support), plus it comes with a brand new preview and rendering engine called the Mercury Playback Engine. Editing HD video in Premiere Pro CS4 was slow and unwieldy, as the software struggled to play anything more than a single stream with minimal effects, even on a high-spec PC. Premiere Pro is the most sophisticated video-editing software available for Windows PCs, but until now it had a big problem: preview performance.