feature live news and sport
are handled in parallel for their conversion requirements. Multiple servers running powerful GPU cards enable the frame rate conversion process occurring as an integrated frame by frame conversion, with different servers addressing different parts of the source video in parallel and each server running concurrent jobs. Upon completion of processing, these parts are stitched back together, with audio and ancillary data added back to the content, and delivered as a whole converted product ready for distribution. All the while, Cinnafilm GPU based algorithms ensure that the content being so quickly delivered meets a high quality frame rate conversion.
The Cinnafilm plugin provides temporal and spatial image resampling to convert source video and image files to any new frame rate or resolution. With a motion compensated engine delivering accurate motion vector data, the RadiantGrid Platform can interpolate new frames for any desired delivery specification or standard. With a tera- flop of computational power available, the plug-in enables users to stack critical operations into a single conversion project. These operations include resolution scaling (mobile device to 4K); frame-rate conversion (any to any); standards conversion (525, 625, 720, 1080, 2K, 4K); interlaced, progressive, and pulldown interchange; automatic cadence correction; mixed pulldown (60i + 24p) with broken-pulldown pattern repair; accurate motion blur modeling; reporting and notification; and timecode preservation (drop frame/ non drop frame) (See Diagram 1). This new approach to standards conversion and other critical processing tasks offers the industry a particularly compelling reason to transition from baseband to file-based workflows. While conventional standards conversion typically is performed four to six times slower than real time, grid-enabled conversion supports faster-than-real- time conversion, with speed
Diagram 2.
In a game- changing new approach to standards conversion, the RadiantGrid platform leverages its media transformation and parallel processing engine along with Cinnafilm motion compensation to deliver outputs boasting excellent
image quality in record time.
depending on how the user scales its servers and GPUs. Because content remains in the file-based domain (and within editors such as Final Cut Pro and Avid Media Composer), broadcasters realise the same flexibility and quality they would when working with high-end hardware systems in the baseband domain.
The workflow applied
One of the world’s leading sports networks has looked to the RadiantGrid automation platform for a significant part of its file-based operations, installing a system to handle grid-based transcoding with standards conversion from PAL to NTSC with high-quality motion compensation.
Diagram 1.
Looking for a solution for the network's Euro 2012 coverage, this sports broadcaster had sought to perform standards conversion in the file domain for efficiency, but was concerned about the lack of existing solutions that would maintain the real-time processing speeds it had known with more traditional baseband workflows. File-based solutions for high-quality standards conversion typically had been from four to six times slower than real time, largely because of the heavy computational challenges involved in managing this type of transcode along with motion compensation. In fact, the solution demonstrated its ability
to complete a single file much faster than real-time across a four-server grid configuration. The network did not need one file done that fast, but rather, was looking for a balance that would allow for four files to be done simultaneously in just under real-time. Due to RadiantGrid’s TrueGrid capabilities they were able to tune their balance of gridded transcoding across the CPU/GPU combination to accommodate this goal.
Successfully implemented for Euro 2012, the platform managed various processes as part of a workflow chain that collected the match content from games, then distributed and conformed it into US standards formats commonly used in the Quantel and Avid edit suites at the network’s US-based facilities. Within this workflow, EVS HD MXF 1080i 50 PAL (Op1a variation with MPEG-2 essence) content was converted to QuickTime DVC Pro 720p 59.94 NTSC content. This is a very difficult conversion not only because writing to QT can be a slow transcode, but also because the conversion from 50 to 60 with high-action sports must be compensated for during the move from PAL to NTSC. Further complexity is added by the interchange from interlaced to progressive, with associated down-scaling (See Diagram 2).
With specific storage I/O requirements configured to handle 600-700 MB/s speeds on the backplane and the
‘RadiantWorker’/server ratio tuned to a sweet spot within conversion thresholds, the RadiantGrid platform leverages internal allocation of CPU and GPU resources to achieve faster- than-real-time end-to-end conversion for the network. The resulting system is organised as one giant super- computer with 10Gbps I/O to a high- density, high-speed storage array. The grid-enabled processing of virtual
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