Quote:
Originally Posted by qyot27
Ok, let's sort this all out.
A) Blu-ray itself doesn't support lossless video - it only supports MPEG-2, VC-1, and H.264*. Lossless was only mentioned because 135 MB/s (that's megabytes per second) is above the datarate that a YUV stream would be without any sort of compression whatsoever, meaning that compressing with HuffYUV would be more size efficient, even if the stream were 60fps. You were confusing Mbps (megabits per second) for MB/s (megabytes per second). 'Bits per second' is the standard way of expressing video datarates - and 135 Mbps = 16.875 MB/s (conversely, 135 MB/s would be equal to 1080 Mbps, or 1.08 gigabits per second).
*Yes, H.264 does have a lossless mode, but I severely doubt that's acceptable on a video Blu-ray Disc. Anyone, feel free to correct me if I'm wrong on that.
B) Blu-ray has a maximum limit for the video bitrate - that limit is 40 Mbps (or in megabytes, 5 MB/s). And at 40 Mbps, H.264 or VC-1 will outperform MPEG-2 in visual quality retained, simply because they're newer standards and more complex (barring, of course, crappy masters and inept authoring houses). The benefit of using MPEG-2 over H.264 or VC-1 is not in visual quality, it's in encoding speed - even my computer, as ancient as it is next to today's bargain setups, can encode HD MPEG-2 with decent enough speed. H.264 or VC-1 compared to MPEG-2 isn't 'more compression' it's 'more refined compression'. It's like the difference between using MS Video 1 and Sorenson 3 - ok, I just pulled that out of thin air, but basically I mean that newer, more capable solutions exist, so it makes little sense (outside of sheer encoding speed) to fall back to an older standard like MPEG-2. Of course, none of that matters if you're simply using Blu-ray as a data disk, in which case anything goes.
That said, knowing the specific stream requirements (for all three of the formats) and eccentricities of the available muxing programs to deal with the needed file structure would be useful, as I'd like to experiment with doing Blu-ray compatible MPEG-2 and H.264 encodes of some of my own content, but I don't even have a Blu-ray player to test it on, so it's still a tad premature in my case.
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if Blu Ray is only storage and streamed through MPC
at full uncompressed HD 1920x1080 is 6.22MB per frame with RGB@8bit image at 24fps this is ~149.9MB/s
for B&W which is my film, 50MB/s or 400Mb/s so to squeeze down to VC-1 spec, i'd need to compress by a factor of 3.
if the audio is 4.1, L, C, R, S, LF, PCM 24-bit, 96kHz, i haven't worked this out yet. adding the bitrate of the audio chain.