Up until now, I've only used my system to playback/edit DNxHD 145 that's been captured elsewhere and that's worked fine.
The error happens about 3 seconds into every capture (v6.0, 1080i Project, DNxHD 145 via HDMI). If I switch project tab over to 1080P and then capture @ DNxHD 45, all is well. This is on a 3.0 ghz T3400 Dell w/ 4GB ram. Is it just absurd to attempt capturing DNxHD145 onto a single external SATA drive? Is a RAID configuration now mandatory or could the overrun be caused something else? Thanks for any tips...
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How is the external drive connected -- eSATA, USB, Firewire? The fact that your DNxHD 45 works fine to the drive is pretty clearly a throughput issue.
DNxHD 145 is a little over 18MB/sec not including audio. If you're capturing to an external drive via USB, you're approaching the zone where it might not be able to keep up, depending on the drive and the quality of the controller in the enclosure... Particularly if you're using one of those smaller 2.5" bus-powered USB drives which are almost always 5200RPM drives and pretty slow.
You don't necessarily need RAID for DNxHD, a good 7200RPM (or 10k) SATA-connected drive should be able to keep up fine. But a pair striped would always be better :)
ManChicken: How is the external drive connected -- eSATA, USB, Firewire?
How is the external drive connected -- eSATA, USB, Firewire?
Thanks, MC. I've been trying the capture two different ways, to the same kind of bare 7200 SATA drives: One way is internal SATA, the other is eSATA into an external dual dock unit that holds two removable bare drives. Supposedly, I should be able to make that contraption a Raid.
ManChicken: You don't necessarily need RAID for DNxHD, a good 7200RPM (or 10k) SATA-connected drive should be able to keep up fine. But a pair striped would always be better :)
That's what I was thinking. I don't have any 10Ks, though.
Watch your CPU performance while you are capturing. The T3400 is an old core2duo system. Capture of Dnx145/Dnx220 requires minimum of 8 cores. Same for most other HD formats when using software codecs.
The CPU is probably close to 100% when capturing 1080p Dnx 36. This format still might fail if you capture for a long time (different media will change the CPU performance during capture).
dpimmer: Watch your CPU performance while you are capturing. The T3400 is an old core2duo system. Capture of Dnx145/Dnx220 requires minimum of 8 cores. Same for most other HD formats when using software codecs. The CPU is probably close to 100% when capturing 1080p Dnx 36. This format still might fail if you capture for a long time (different media will change the CPU performance during capture).
Thanks for your suggestion, dpimmer. I'll take a look at CPU as you suggest. I'm getting help from AJA on the matter.
What's interesting are these System Recommendations on the AJA i/o express support page.
It indicates that the AJA box needs 8GB ram under Win7, and a Dual Core 2.26 Ghz machine with just 4GB ram is acceptable under Win Vista64. I'm going to check if my Dell core2duo system can capture DNxHD145 using v5.5 on my Vista64 partition.
dpimmer: Watch your CPU performance while you are capturing.
Watch your CPU performance while you are capturing.
You're right. My system's CPU was at 88%+ spikes capturing DNxHD 45 in a 2997 Project. Right up there at 100% at DNxHD145, before errors.
However, I was able to capture MXF 1:1 in either 2997 or 5994 Project, but 1 min of HDMI from a lockdown camera weighed-in at 7.3GB. I proceeded to transcode that 1 min test clip to DNxHD 145 and it took just 1:30 mins. That I can live with, but when I tried playing the transcoded clip in the source monitor, I received Exception: Legend Audio Communications error, hardware underrun.
Tried same 1 min. transcode test to DNxHD 145 using V6.0, and no "Legend" errors, thankfully.
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