Mainconcept 7.7 encoding in parallel im?possible

[codeguru]

Hi I have a question about the mainconcept H.264 v 7.7

My os is Windows 7 64 bit and my video tool is Magix Videodeluxe MX Plus (Version 17).

The h.264 has such a bad cpu usage (about 55%) that I wanted to encode in 2 sessions in parallel.... but when starting the second encoding session I get an error message "error loading the Mainconcept encoder. The encoder returned an unknown error".

Is that feature disabled in this encoder?

WMV and DivX are not restricted and I already did that in 5 sessions in parallel. But now I wanna take advantage from the better encoding.... I have only 20 Kbit Upstream so I'd like to crunch my clips as much as I can.

[Asmodian]

Why not use x264?

(sorry I know nothing about Mainconcept's encoder) :o

[codeguru]

my program is fixed to the Mainconcept h.264 encoder

[Sagittaire]

Why make encoding in parrallel? Low fps is certainely speed limitation from the source (slow pre-process filter, Disk access ...)

Total time will be even better if you make encoding successively (Disk access will be better if you have high framerate).

[codeguru]

I have a 8 months old Dell XPS15 notebook with Q2830 CPU and 7200 rpm harddisk. Using the WMV codec I get about 25-40 fps when encoding 1080p25 10 Mbit material to 2 mbit WMV in 720p25, and about 95% of CPU usage. And there are no filters, it is just copy and paste on the timeline.

The slowlyness of the H.264 encoding is for sure not caused by slow hard disk.... and it shows on all 8 CPU cores the same average usage. A bad filter is for example not multithreaded and would show up 100% on one CPU core while the other 7 are doing nothing.

So back to the maths... when processed in real time the material is read by 1,2 MB/sec from the harddisk :-) and the hard disk makes 70 MB/sec in continous read and write. The output in 2 Mbit is 250 KByte/sec.

That can be done on a Class 10 card (20 MB/s read) without any influence on the performance.

Anyway this is all OT - why does the mainconcept h.264 not work in 2 sessions?

[Atak_Snajpera]

why does the mainconcept h.264 not work in 2 sessions?
why don't you ask mainconcept support?

[Blue_MiSfit]

Or better yet, contact the company that makes this "Magix Videodeluxe" software.

It's entirely possible that they've configured the Mainconcept encoder in an unusual way.

[shon3i]

AFAIK Magix can use x264 through vfw which is not bad idea nowdays, since there is internal output to mkv/mp4/264, there will be no vfw limitations.

[Sagittaire]

So back to the maths... when processed in real time the material is read by 1,2 MB/sec from the harddisk :-) and the hard disk makes 70 MB/sec in continous read and write. The output in 2 Mbit is 250 KByte/sec.

Well with 2 sessions you read 2 files sources and write 2 output sources. Moreover with optical disk you have 4 access and certainely not 70 MB/sec in this situation. So back to the maths ... ;-)


Anyway this is all OT - why does the mainconcept h.264 not work in 2 sessions?

Perhaps because mainconcept write the same stat files if you make two pass encoding ... ???

Anyway mainconcept is build to use 16 thread. You have certainely another problem. Try to force 8 thread with only one session encoding.

[Blue_MiSfit]

Where did he say he's using an optical disk?

I very strongly doubt there is an I/O bottleneck going on here.

[Sagittaire]

Where did he say he's using an optical disk?

I very strongly doubt there is an I/O bottleneck going on here.

magnetic disk. You can have problem if your disk is really fragmented with multiple sessions (I have this problem recently).

[Blue_MiSfit]

Sure, if he was trying to do 5-10 encodes in parallel I could see this being an issue, but not with 1-2. He should be seeing some performance scaling.

One way I like to check whether or not I'm seeing a hard drive bottleneck is by using the Windows 7 Resource Monitor. The Disk tab has a tab named "storage", which has a value named "disk queue length". My understanding is that if this value is above roughly 2x the number of spindles in the logical disk, you're probably thrashing the disk and causing a bottleneck. The "active time" field is interesting too.