Hardware encoding is more pervasive with Intel’s Quick Sync embedding CUDA GPUs inside GPUs plus NVIDIA GPUs have MPEG NVENC encoding support so how does it compare with software encoding? For HEVC, can Xilinx’s FPGA solution be a boost in terms of quality or cost compared to software encoding?
Jan Ozer has stepped up to the plate to put this all to the test analysing how many real-time encodes are possible on various cloud computing instances, the cost implications and the quality of the output. Jan’s analytical and systematic approach brings us data rather than anecdotes giving confidence in the outcomes and the ability to test it for yourself.
Over and above these elements, Jan also looks at the bit rate stability of the encodes which can be important for systems which are sensitive to variations such services running at scale. We see that the hardware AVC solutions perform better than x264.
Jan takes us through the way he set up these tests whilst sharing the relevant ffmpeg commands. Finally he shares BD plots and example images which exemplify the differences between the codecs.
Recycling may be good for the environment, but it turns out it’s good for bit rate too. Remembering that MPEG (and similar) video compression includes splitting the picture into blocks, decomposing them into basic patterns and also estimating their motion, this talk wonders whether calculations made on the blocks and the motion of these blocks done on the SD picture can be re-used on the HD picture and then again on the UHD picture. If so, this would surely reduce the computation needed.
“The content is perceptually identical,” explains Alex Giladi from Comcast, “…the only difference is how many pixels it occupies.” as he highlights the apparent wastefulness of ABR encoding where the same video is taken in multiple resolutions and encoded independently. The technique starts by analysing the lowest resolution video for motion and re-using the calculations at a higher resolution. Naturally there are aspects which can’t be captured in the lower resolutions, but also there are sensitivities to the bitrate so Alex explains the refinement options which have been developed to adapt to those.
As the talk wraps up, Alex presents the results found which show that the quality is not degraded and there is a better than 2x speed increase. Finally we look at a real-life flow of encoding.
From VideoLAN’s Video Dev Days event 2018, this talk discusses the latest updates to x265, a free software library and application for encoding video streams into the H.265/MPEG-H HEVC compression format, released under GNU GPL.
Pradeep Ramachandran, Principal Engineer at Multicore takes us through:
Content distributors and aggregators adding HEVC to their delivery pipeline will have plenty of codec options, but who has the time to evaluate their features, output quality, and performance?
No worries—codec specialist Jan Ozer has done the work for you. He’s evaluated leading contenders like x265, MainConcept, Beamr, Intel, and NTT and he’ll share his results. You’ll walk away from this session with a much clearer picture of the strengths and weaknesses of your HEVC encoding options for VOD streaming. Watch
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