2008编码器枪战

所有关于编解码器的讨论, 发布商, 眼球, 商业模式, 和货币化, the actual rendering of your video file is where the rubber meets the road in the streaming video market. 在这篇综述中, I first look at the compression capabilities for Adobe Creative Suite 3 and Apple Final Cut Studio 2. Then I review the primary multiformat batch compression tools: Grass Valley ProCoder, 索伦森挤压, 和Telestream Episode Pro.

My primary focus is on the quality of the output produced by each tool. This includes the quality of the deinterlacing algorithms deployed by the tool and the quality of the 闪光, Windows媒体, 和H.每个工具产生264个文件.

Adobe Premiere Pro 3.1.1
Premiere Pro is the primary video production tool in the Adobe CS3 Production Premium suite, and the Adobe Media Encoder is the primary tool for producing streaming output from Premiere Pro. While the Adobe Media Encoder is certainly sufficient for casual, 原型的工作, the lack of automation features and several feature gaps—particularly relating to H.264 and 闪光 video production—make the tool less than optimal for serious streaming production.

One big gap in the Adobe offering is the total lack of automation, 是否批, 滴, 或者看文件夹. You can encode one file at a time, and you can’t pause encoding—you have to cancel it. 公平地说, most editors don’t offer encoding automation, 但苹果有, 与压缩机, Avid也是如此, 包括索伦森挤压 4.5使用Avid Xpress Pro. Unlike other encoding tools on the market, Adobe offers no upgrade path to a more powerful program, 或者硬件编码支持, 或者聚类编码. 事情就是这样，仅此而已.

Format support is good on the Windows version of CS3, 哪里可以生产Windows媒体, 闪光, QuickTime, 和RealVideo文件. 在Mac上, 然而, you can output only 闪光 and QuickTime; RealVideo and particularly Windows媒体 users will need to seek a third-party solution.

Adobe’s workflow can be confusing to newbies, but most users should quickly be able to master what to do and where. The first challenge is which export function to use. 添加Adobe媒体编码器后, Adobe retained the File > Export > Movie function, 可以产生AVI, QuickTime, 以及其他一些文件类型. I use this as the preferred workflow when producing intermediate files for encoding elsewhere, but I use File > Export > Adobe Media Encoder for all streaming production.

Premiere Pro’s deinterlacing and scaling quality is generally good, but there are higher-quality solutions out there, including Compressor at its glacial "Best" deinterlacing setting 和Telestream Episode Pro. Enabling deinterlacing can be a challenge, though things appear to be cleared up in Premiere Pro CS3.

具体地说, 在以前的版本中, the deinterlace checkbox in the Adobe Media Encoder (and the Make Movie function) often didn’t work with video produced with progressive presets, and this seemed dependent upon the selected output format. 甚至在CS3，直到版本3.1.1, deinterlacing doesn’t appear to be working in the preview, though the Encoder does actually deinterlace when producing all formats. 对于以前的版本, often you had to deinterlace on the timeline by right-clicking the video, 选择字段选项, and then choosing the Always Deinterlace option.

具有讽刺意味的是, though Windows媒体 is clearly the least likely format that Adobe would want to push their users towards, it’s the best-supported format of the big three. 功能集已经完成, including the ability to produce multiple-bitrate files, 而且质量也很有竞争力, though definitely a step behind the leaders in high-motion footage. As with all encoders, I analyzed Windows媒体 (和H.264 files) in Inlet Technologies Semaphore, a video analysis tool which revealed that Adobe inserted keyframes at 67% of scene changes that I checked, same as the Windows媒体 Encoder and second only to Compressor. 数据速率峰值约为570Kbps, compared to 590Kbps for the Windows媒体 Encoder, indicating a relatively smooth file that should stream and play effectively.

In contrast, the Adobe Media Encoder has a number of issues with H.264 production, including some potential showstoppers. By way of background, in the Encoder, you can produce H.264 files using one of two "formats," with the H.264 format producing MP4 files, and the QuickTime format producing MOV files. H.264 option provides more extensive encoding parameters, but can’t produce files that are hinted for streaming. Neither alternative lets you elect the Fast Start option, so files produced via the Adobe Media Encoder won’t progressively download; they’ll start playing only once fully downloaded.