Playback Buffer

[PaulTV]

After all these years I'm still a trifle fuzzy over the playback buffer.

Adjusting buffer size allows me to pre fill and then play for as long as the buffer lasts - this using an "intensive" plugin.

Whilst this is happening, my CPU is operating at around 20% running at 4.5GHz (16 threads all cores running) my RAM usage is about 6GB total inc. OS, so on this system I have 25GB free, my disc throughput is about 8mbs - peanuts considering my quad SSD runs at 1700mbs read - so, with all my resources under zero stress, and little used, why can the system not provide me with better stutter free playback?

Obviously,various plugins from other vendors are outside the Edius/GrassValley comment arena, but it really appears strange that with a powerful system Edius and approved plugs such as NewBlue are unable to access or use properly the available resources.

Why can't Edius keep filling the buffer, in a look ahead manner, using available RAM and CPU resources, rather than simply running out of steam?

Paul :-)

[Bluetongue]

Paul
To give you an idea of how bad NewBlue adaption of GPU processing is
I have an old ATI HD6950 which I can control the clock frequencies and for best results I need to reduce the clock to 600mhz for NB
BUT this then reduces the capabilities of Prodad, NEAT and the GPU transitions
Recently I attempted to upgrade my GPU to a ATI R9 290x with disastrous results over doubling the time to fill the buffer with NB, all the others loved it, as I use NB a lot I have gone back to the old card which gives the best for NB but as a compromise I have set it to 900mnz and get the worst of both worlds

It may be different with a nvidea card but have not tested
ALL run in RT with the fast card but it cuts down using multitracks with NB, but as you have found everything is just idling along

Thats my observation anyway
Regards Barry

[Jerry]

Paul, what is the intensive plugin and filter? What type of clip?

[PaulTV]

Hi Jerry

I was testing the NB Diffuse filter in Colourfast which is pretty slow - on a 1080 HD HQX file - also Saphire Diffusion and Looks diffusion - all used to play well in realtime before Edius went 64bit and never have since, despite the increases in computing spec's across the board - I note that Edius does use full CPU when loaded with say, 10 soft focus filters on a single clip - so I guess the plugins are not written to take advantage of the leverage within a system - I still wonder why Edius prefill buffer is a one shot affair, fill, then empty, can it not look ahead and keep filling as the system is running at 30% capacity during this process?

Off out to catch me a pheasant for my dinner..later

Paul :-)

[Jerry]

Hi Jerry

I was testing the NB Diffuse filter in Colourfast which is pretty slow - on a 1080 HD HQX file - also Saphire Diffusion and Looks diffusion - all used to play well in realtime before Edius went 64bit
Paul :-)

All three of those play realtime on my machine. The slowest is Looks. NB Diffuse filter buffer climbs as it plays. New blue did some improvements to playback with the new versions. Try the download that Marcus suggested in the Lounge thread. Sapphire Diffuse is just plain realtime from the get go. Looks Diffusion will play all day but the buffer is at 3. It is smooth and audio isn't stuttering. If I do a buffer pre-fill the 1 minute test clip will play all the way through with a blue bar and the buffer at 275/300.

[PaulTV]

Jerry, that's odd, is your system more beefy than mine - enough to cause this difference.. I'm gonna check further...

Just to be clear are you talking: 1080 project (10 bit or 8 bit?) using HQX or HQ, single file on timeline, no other filters?

Paul :-)

[Jerry]

I was using a 1920x1080 59.94i HQX Super Fine 60 sec clip within in an 8bit project setting.
It all was good.

In 10bit the Sapphire diffuse buffer climbed until it hit 300 and then hovered there.

The Colorfast Diffuse would play but with a 3 to 7 buffer range. The 60 sec clip would play through.

The Looks diffuse would play but with a 3-5 buffer range. The entire clip would also play through.

On the Colorfast and Looks effects, doing a buffer pre-fill would get both clips to play all the way with the lowest buffer of 230 belonging to the Looks effect. Both clips' buffers dropped very slowing over the 60 second clip. Light blue bars would appear above the timeline on both clips.

If you are using 50p or 60p, playback tanks.