SxS in field Offload

Alex Leith · December 5th, 2007, 11:32 AM

Thanks Steven

Chris Forbes · December 7th, 2007, 12:42 PM

The hitch is a linix based device also, so it may be possible to install the drivers for the SXS.

Also this battery powered USB hub might come in handy. For providing power to larger hard drives.

http://www.cyberpowersystems.com/pro.../cph420mp.html

Chris Forbes · December 31st, 2007, 08:03 PM

Got my Sony USB Card reader. Not only is it Non-Buspowered but the AC adapter is outputting 12v@3A making it useless for anything but desktop offloading.

One unexpected bonus is that the ac adapter will run the camera and is quite a bit more compact than the Charger/Ac Adapter that comes with the camera.

But for 234.00 ? ? ?

Graeme Fullick · December 31st, 2007, 08:19 PM

Chris,

What sort of transfer rate are you getting through USB?

I don't like plugging the camera in as a USB device - so I might have to reluctantly buy one.

Maybe the bus power is not enough to sustain high transfer rates for these cards????

Raymond Schlogel · December 31st, 2007, 08:58 PM

Wow, non-buspowered? Really? Ouch. Real tempted to cancel my order for one, that could be a deal breaker.

- Ray

Chris Forbes · January 1st, 2008, 04:30 PM

I am getting the same through the USB reader as through the camera. I really think this is a limitation of USB. The reason I got the reader is so I could do downloads while i was still shooting. And to save hours on the camera. High hours really hurt the resale value.

Thierry Humeau · January 1st, 2008, 07:07 PM

I think our hopes to see USB-2 transfer speed hit the roof are dimmed. Despite having a raw data rate of 480mbps, it looks like USB-2 can only acheive 40mpbs. Here is an interesting article on USB-2 speed:

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
How fast is USB 2.0?

USB 2.0 has a raw data rate at 480Mbps, and it is rated 40 times faster than its predecessor interface, USB 1.1, which tops at 12Mbps. Originally, USB 2.0 was intended to go only as fast as 240Mbps, but in October 1999, USB 2.0 Promoter Group pumped up the speed to 480Mbps.

As far as we know, effective rate reaches at 40MBps or 320Mbps for bulk transfer on a USB 2.0 hard drive with no one else is sharing the bus. Flash Drives seem to be catching up too with the some hitting 30MB/s milestone. For all we know, USB interface could become become the bottleneck for flash drives as early as 2008.
Additional notes from Alex Esquenet - our engineer friend based in Belgium: "A fast usb host can achieve 40 MBytes/sec. The theorical 60 MB/sec cannot be achieved, because of the margin taken between the sof's (125 us), so if a packet cannot take place before the sof, the packet will be rescheduled after the next sof. On top of that, all the USB transactions are handled by software on the PC. For instance, a USB host on a PCI bus will send or receive the data via the PCI bus; the stack will prepare the next data in memory and receive interrupt from the host."
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Bernard Racelis · January 1st, 2008, 10:30 PM

Quote:

Originally Posted by Thierry Humeau

... 40MBps or 320Mbps for bulk transfer on a USB 2.0 hard drive ...

I interpret this as 40 megabytes/sec = 320 megabits/sec (1 byte = 8 bits), which is still fast (potentially), considering that the EX1 records HQ video at 35 megabits/sec.

Andrew Wilson · January 2nd, 2008, 02:02 AM

How does the USB reader work if a shot spans across two cards?

I assume that if you plug the camera into the computer then it offloads all the shots regardless if it spans 2 cards.

Also, has anyone tried to offload a continuous shot that spans 3 cards? How would you do that? Does anyone even own 3 cards yet???

Bernard Racelis · January 2nd, 2008, 09:01 AM

I haven't shot a clip yet which spans across cards, but from reading the EX Browser guide, you copy the files from separate cards (2 or more, I assume) into a single location in the hard drive.

It also mentions that the software uses a "Clip ID" in the files, not the filenames. I would think that the separate files from the same clip will have the same ID, and the software uses this ID to link the files together into one clip.

Bernard Racelis · January 2nd, 2008, 10:45 PM

I've just tested the above and these are the steps on how I combined the files from 2 cards together:

(1) Create a folder in the hard drive (example D:\video\test1)

(2) Using the EX Clip Browser, copy the clip from one card by dragging it from the SxS card to the folder on the hard drive (D:\video\test1)
This creates the XDCAM "BPAV" directory structure within the folder (D:\video\test1\BPAV) and then copies the clip.

(3) Copy the other file from the same video from another card by dragging it into the same folder.

(4) The result is you have multiple clips (folders) in the BPAV/CLPR folder:

Code:

D:\video\test1\BPAV>dir CLPR

 Directory of D:\video\test1\BPAV\CLPR

01/02/2008  09:49 PM    <DIR>          .
01/02/2008  09:49 PM    <DIR>          ..
01/02/2008  09:49 PM    <DIR>          083_0424_01
01/02/2008  09:48 PM    <DIR>          083_0424_02

And there is another folder within the BPAV/TAKR directory which links the two clips together.

Code:

D:\video\test1\BPAV>dir TAKR

 Directory of D:\video\test1\BPAV\TAKR

01/02/2008  09:49 PM    <DIR>          .
01/02/2008  09:49 PM    <DIR>          ..
01/02/2008  09:48 PM    <DIR>          083_0424

And it appears as one clip in the EX Clip Browser.

(5) When you export/convert to an MXF, the files are combined into one MXF file.

December 5th, 2007, 11:32 AM	#16
Alex Leith Major Player Join Date: Mar 2005 Location: Northampton, England Posts: 500	Thanks Steven __________________ Alex

December 31st, 2007, 08:19 PM	#19
Graeme Fullick Major Player Join Date: Mar 2005 Location: Newcastle, Australia Posts: 337	Chris, What sort of transfer rate are you getting through USB? I don't like plugging the camera in as a USB device - so I might have to reluctantly buy one. Maybe the bus power is not enough to sustain high transfer rates for these cards???? __________________ Graeme

December 31st, 2007, 08:58 PM	#20
Raymond Schlogel Regular Crew Join Date: Sep 2004 Location: Austin Texas Posts: 162 Images: 3	Wow, non-buspowered? Really? Ouch. Real tempted to cancel my order for one, that could be a deal breaker. - Ray __________________ www.undergroundplanet.com

January 1st, 2008, 07:07 PM	#22
Thierry Humeau Telecam Films Join Date: Apr 2006 Location: Washington DC Posts: 723	I think our hopes to see USB-2 transfer speed hit the roof are dimmed. Despite having a raw data rate of 480mbps, it looks like USB-2 can only acheive 40mpbs. Here is an interesting article on USB-2 speed: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> How fast is USB 2.0? USB 2.0 has a raw data rate at 480Mbps, and it is rated 40 times faster than its predecessor interface, USB 1.1, which tops at 12Mbps. Originally, USB 2.0 was intended to go only as fast as 240Mbps, but in October 1999, USB 2.0 Promoter Group pumped up the speed to 480Mbps. As far as we know, effective rate reaches at 40MBps or 320Mbps for bulk transfer on a USB 2.0 hard drive with no one else is sharing the bus. Flash Drives seem to be catching up too with the some hitting 30MB/s milestone. For all we know, USB interface could become become the bottleneck for flash drives as early as 2008. Additional notes from Alex Esquenet - our engineer friend based in Belgium: "A fast usb host can achieve 40 MBytes/sec. The theorical 60 MB/sec cannot be achieved, because of the margin taken between the sof's (125 us), so if a packet cannot take place before the sof, the packet will be rescheduled after the next sof. On top of that, all the USB transactions are handled by software on the PC. For instance, a USB host on a PCI bus will send or receive the data via the PCI bus; the stack will prepare the next data in memory and receive interrupt from the host." >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> __________________ Thierry Humeau, DoP Télécam Films www.telecamfilms.com

January 2nd, 2008, 10:45 PM	#26
Bernard Racelis Regular Crew Join Date: Dec 2007 Location: New York City Posts: 82	I've just tested the above and these are the steps on how I combined the files from 2 cards together: (1) Create a folder in the hard drive (example D:\video\test1) (2) Using the EX Clip Browser, copy the clip from one card by dragging it from the SxS card to the folder on the hard drive (D:\video\test1) This creates the XDCAM "BPAV" directory structure within the folder (D:\video\test1\BPAV) and then copies the clip. (3) Copy the other file from the same video from another card by dragging it into the same folder. (4) The result is you have multiple clips (folders) in the BPAV/CLPR folder: Code: D:\video\test1\BPAV>dir CLPR Directory of D:\video\test1\BPAV\CLPR 01/02/2008 09:49 PM <DIR> . 01/02/2008 09:49 PM <DIR> .. 01/02/2008 09:49 PM <DIR> 083_0424_01 01/02/2008 09:48 PM <DIR> 083_0424_02 And there is another folder within the BPAV/TAKR directory which links the two clips together. Code: D:\video\test1\BPAV>dir TAKR Directory of D:\video\test1\BPAV\TAKR 01/02/2008 09:49 PM <DIR> . 01/02/2008 09:49 PM <DIR> .. 01/02/2008 09:48 PM <DIR> 083_0424 And it appears as one clip in the EX Clip Browser. (5) When you export/convert to an MXF, the files are combined into one MXF file.

December 7th, 2007, 12:42 PM	#17
Chris Forbes Regular Crew Join Date: Mar 2006 Location: Salt Lake City, Ut Posts: 155	The hitch is a linix based device also, so it may be possible to install the drivers for the SXS. Also this battery powered USB hub might come in handy. For providing power to larger hard drives. http://www.cyberpowersystems.com/pro.../cph420mp.html

December 31st, 2007, 08:03 PM	#18
Chris Forbes Regular Crew Join Date: Mar 2006 Location: Salt Lake City, Ut Posts: 155	Got my Sony USB Card reader. Not only is it Non-Buspowered but the AC adapter is outputting 12v@3A making it useless for anything but desktop offloading. One unexpected bonus is that the ac adapter will run the camera and is quite a bit more compact than the Charger/Ac Adapter that comes with the camera. But for 234.00 ? ? ?

January 1st, 2008, 04:30 PM	#21
Chris Forbes Regular Crew Join Date: Mar 2006 Location: Salt Lake City, Ut Posts: 155	I am getting the same through the USB reader as through the camera. I really think this is a limitation of USB. The reason I got the reader is so I could do downloads while i was still shooting. And to save hours on the camera. High hours really hurt the resale value.

January 2nd, 2008, 02:02 AM	#24
Andrew Wilson Tourist Join Date: Nov 2007 Location: Vermont, USA Posts: 123	How does the USB reader work if a shot spans across two cards? I assume that if you plug the camera into the computer then it offloads all the shots regardless if it spans 2 cards. Also, has anyone tried to offload a continuous shot that spans 3 cards? How would you do that? Does anyone even own 3 cards yet???

January 2nd, 2008, 09:01 AM	#25
Bernard Racelis Regular Crew Join Date: Dec 2007 Location: New York City Posts: 82	I haven't shot a clip yet which spans across cards, but from reading the EX Browser guide, you copy the files from separate cards (2 or more, I assume) into a single location in the hard drive. It also mentions that the software uses a "Clip ID" in the files, not the filenames. I would think that the separate files from the same clip will have the same ID, and the software uses this ID to link the files together into one clip.