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A comment on $89 Exynos4412 1.7Ghz ARM Cortex-A9 Quad-Core 2GB. Parent comment

Re:$89 Exynos4412 1.7Ghz ARM Cortex-A9 Quad-Core 2GB by halter73 on Friday December 28, 2012 @02:23AM (#4976867)
But couldn't you just have each core start at a different key frame?
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Re:$89 Exynos4412 1.7Ghz ARM Cortex-A9 Quad-Core 2GB by miahi on Friday December 28, 2012 @02:52AM (#4976928)
To start encoding at different times with each core you would need a really fast (read: expensive) storage (every core will need a steady stream to compress, if you have 64 cores you need a storage that can handle 64 parallel requests really fast or a lot of RAM to cache everything) and the chips have to handle really heavy I/O. The current many-core ARMs only have a small amount of dedicated RAM for each core.

Also, keyframes are not known from the start in many encodings. A keyframe is inserted when the difference between a frame and the next one is big; this can only be detected when encoding, or with a multi-pass encoding.

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Re:$89 Exynos4412 1.7Ghz ARM Cortex-A9 Quad-Core 2GB by rorrr on Friday December 28, 2012 @06:07PM (#4980078)
Even cheap modern SSDs can handle 400-500 MB/sec reads. You can consume 500 MB chunks of video into RAM and eliminate I/O bottleneck completely.

Video encoding is CPU-bound, not I/O bound.

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