Review: Sorenson Squeeze 5
Users can create multiple-bitrate files for distribution via a streaming server by dragging a special MBR template onto their source clips. MBR parameters can then be saved into a custom preset for repetitive use.
There is no control for enabling Squeeze to insert key frames at scene changes, but analysis in Inlet Semaphore revealed that Squeeze did so automatically about 50% of the time. Squeeze encodes all files using the main profile, which is appropriate, but with no control for choosing between the main and baseline profiles or B-frame interval, something advanced compressionists may wish they had.
There are also no encoding tweaks such as those provided by the Windows Media Power Toy, which is a feature that is starting to appear in more and more encoding tools, such as Rhozet Carbon Coder and Inlet’s Fathom, albeit at a much higher cost. Note that Squeeze does expand the encoding parameters when producing files using the VC-1 codec, which is the Windows Media 9—Advanced Profile codec, opening a different preset targeted primarily at encoding for Blu-ray production.
From a quality perspective, Squeeze’s WMV quality is very similar to that produced by the Windows Media Encoder and other tools such as Grass Valley ProCoder. The Windows Media format is very mature, and there is little difference between most encoding tools.
VP6 Encoding
For VP6 Flash encoding, Sorenson added support for On2’s VP6-E and VP6-S profiles, with the latter being a lower complexity profile targeted towards cell phones and other low-power devices. Flash-encoding options are very extensive, including most of the controls offered in On2 Flix Pro’s video/audio tab and VP6’s advanced features tab.
For Flash, Sorenson lets users select whether to enable auto key frames with a threshold slider and set the maximum key frame interval. There are also minimum and maximum quality sliders, a VBR variability slider for customizing VBR and CBR parameters, a checkbox that allows Squeeze to drop frames to maintain the data rate, a sharpness versus smoothness slider, and noise preprocessing. Users can also customize minimum and maximum 2-Pass VBR data rate values, which default to 40% (minimum) and 400% (maximum). Other than ensuring that the auto key frames option is checked, which it now is by default, users can probably ignore these settings and work in the simple view.
I produced a VP6-E test file, which compared favorably to a file produced with On2’s Flix Pro, the gold standard for Flash encoding. Playing the files side by side, I saw virtually no difference in quality, even in the scenes with hard-to-compress backgrounds, which had been a problem for Squeeze in previous versions.
Users can produce both FLV and SWF files, and if they opt for the latter, Squeeze lets them choose an SWF player from among 10 different templates with useful options such as the ability to link or embed the actual video file. The templates are serviceable and will get users going quickly, and Sorenson includes a PDF reference detailing how to create custom templates in the template folder.
Squeeze also lets users encode video with an alpha channel for overlaying over a Flash background, though I didn’t test this feature.
H.264 Encoding
The most significant change for most streaming producers will be Sorenson’s switch to the MainConcept H.264 encoder, which proved spotty in my comparative tests. This is unfortunate because the MainConcept encoder is well-regarded for output quality. More on that in a moment.From a configuration standpoint, users start by choosing format constraints, if any, including the Adobe Flash F4V format. Then they set basic configuration options, which include 1 and 2-Pass VBR (but not 2-Pass CBR) as well as resolution, aspect ratio, frame rate settings, and the like.
There are also H.264-specific settings. Users can choose the profile but not the level, which may frustrate some advanced users, but they can select the number of B-frames and whether to apply context-adaptive binary arithmetic coding (CABAC), a more efficient data-packing algorithm that requires more decompression horsepower. However, encoding effort and slices mean different things in different H.264 encoders, and Squeeze’s help file hadn’t been updated to define these controls.
Video quality was generally good, a nice improvement over the Apple codec Sorenson used in previous versions. Unfortunately, quality suffered frequently after scene changes.
Sorenson has reproduced the problem and promises to have it resolved by the time that the aforementioned patch is released. Note that I didn’t see the same problem when producing H.264 files with the Apple codec in Squeeze 5. If users are upgrading from version 4.5 on the same system, they should still have the Apple codec available in Squeeze 5, and I would recommend using that codec until Sorenson fixes the problem.
Overall, with Squeeze 5, Sorenson took baby steps in some critical new directions, including simultaneous file encoding and switching to the highly regarded MainConcept H.264 codec. Unfortunately, unless it’s your child, baby steps are seldom graceful or particularly effective, and that’s the case here.
Until Sorenson resolves the scene-change issue, I can’t recommend Squeeze for H.264 producers unless they already have the Apple codec on their systems. If users are looking for a dramatic increase in encoding speed from previous Squeeze versions, they’ll see it only if they are encoding many files with different codecs and not if they run a single-codec shop.
After reading this review, check the StreamingMedia.com website for news on the upcoming patch. We’ll review it as soon as it’s available.