2K Cineform 444
Posted by Mike McCarthy on December 14th, 2007 filed in Product ReviewsWhile Cineform’s initial products were developed for broadcast-level HD 10bit 4:2:2 YUV editing, they have added many other features to their compression format, many of which I have had the opportunity to take advantage of during my last few projects. One of the first improvements that was made over a year ago was an increase in the maximum frame size, from 1080p to 2K.
Originally the only way to generate Cineform AVI files at this resolution was to scan film to DPXs, and then convert those image sequences, presumably in After Effects. Interestingly, while being at 2K resolution, these files were being downsampled to YUV colorspace, which improved compression rates and performance, at the expense of the quality certain color information. Eventually the SI-2K camera provided a second root source of Cineform2K imagery, that did not involve converting from an uncompressed source file at any point in the process.  I anticipate we will see 2K data being captured over SDI directly to Cineform files in the near future, if they are not doing so already, as both AJA and BMD have products with the required hardware capability.
The SI-2K brought with it one other new option to the format, which was an alternate pre-debayer RAW ‘colorspace’ instead of the YUV data that was normally being compressed. CineformRAW video files had even better compression ratios, but the only way to take advantage of the benefits of pre-debayered images was by tapping directly into a single sensor imager, as the SI-2K did. This eventually led to a third underlying option, with the development of Cineform 444.
Cineform444 allows full RGB encoding, processing, and mastering of image data, which is the norm in a digital intermediate environment. The RAW files of the SI-2K had the required information for RGB processing, but it hadn’t been fully taken advantage of until that point. DPX filmscans have full RGB info, as do most still images and CGI files. Only ‘broadcast video’ files and formats are limited to YUV. While increasing file sizes and processing requirements, this RGB processing brought the “Cineform Intermediate” to the next level quality wise. Cineform now shows off their format in comparison the the popular HDCam-SR format, which doesn’t directly compare since SR can’t be accessed natively, but it communicates the idea to people who still think in terms of tape formats. I believe SR tapes that are recorded in 444 RGB can be captured directly to Cineform444 via BMD hardware, but I have not had the opportunity to test that myself. I have worked on projects where we captured 444 RGB data uncompressed through a BMD Multibridge, and then later converted parts to Cineform444 to work with. I have also extracted CineformRAW files from the SI-2K directly to full range Cineform444 files. Either way, this workflow has allowed me to work on visual effects shots at full 2K resolution in RGB, on my system at home without a dedicated RAID, and even on my laptop if I could suffer the 12inch screen size.
Around the same time that the Cineform444 capabilites were being developed, the option to include an imbedded alpha channel was added, and the maximum bit depth was increased from 10bit to 12bit. I have yet to take advantage of the 12bit capability, but the embedded alpha channel can be useful for everything from animated titles to visual effects. I find the biggest gains from this development when using Cineform for my After Effects work.
Cineform has also been working to develop a cross-platform solution, so that Cineform compressed media can be easily shared between Macs and PCs. Their first step was to develop a Quicktime wrapper for their original AVI codec. Next, they ported the compression codec to OSX, assisted I am sure, by Apple’s switch to Intel processors. The last steps remaining to be completed are an accelerated CineformRT engine for the new Mac version of PremierePro CS3, and an OSX port of their HDLink conversion tool. At this point Cineform is the only reliable compressed format for transfering video between Windows and OSX systems, besides saving to a DPX sequence, which has obvious disadvantages.
As mentioned in an earlier post, Cineform has recently released a beta of their next improvement to the capabilities of their format, with support for 4K imagery, or higher. Although 4K filmscans could be used as source, their immediate target is data from the Red One camera, with 4K output from the RedCine conversion utility. With wavelet compression for efficient reduced resolution decoding, RGB colorspace, 10 or 12bits of color depth, support for alpha channels, and cross platform compatibilty, Cineform seems well positioned to meet the needs of this emerging market.
Tags: 2K I/O, AJA, Blackmagic, Cineform, Compression, Red One
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