On DM355 (and other single processor systems, like DM6437), Codec
Engine-based codecs are always configured to be 'local', and as such the
overhead introduced by CE is a function call.
There are other (mostly obvious) Linux-introduced overheads on DM355
like user-mode/kernel-mode context switching if your alg requires
processing HW interrupts, virtual-to-physical address translation if
your alg needs to pass buffers to HW accelerators (e.g. DMA), thread
synchronization and pre-emption, cache maintenance if your data buffers
are cached, etc.
There are some further architecture details about DM355 and Codec Engine
here:
http://linux.omap.com/pipermail/davinci-linux-open-source/2007-December/
004847.html
Chris
________________________________
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On
Behalf Of Shawn Ho
Sent: Tuesday, March 04, 2008 10:09 AM
To: Griffis, Brad;
[email protected]
Subject: RE: DM355 or DM6437
Hi,
Thanks for your response, Brad. I recalled that DM355 can run
the codec engine on it. Is there any benchmark information which shows
the processing rate of different codec engines in the DM355? Also, if we
follow the xDM interface to implement our own filter, could we expect a
similar performance?
Another quick question regarding of the DM6437. I just want to
confirm that it seems like there is no ADC in the DM6437 except for the
line/mic in. If so, is there API to get the raw ADC from the line/mic in
without passing thorugh the AIC33 codec module?
Thanks!
Shawn
From: Griffis, Brad [mailto:[EMAIL PROTECTED]
Sent: Tuesday, March 04, 2008 7:28 AM
To: Shawn Ho; [email protected]
Subject: RE: DM355 or DM6437
If you use the DM355 then all of your programming will be done
on the ARM. I imagine you will be limited in the amount of filtering
you can accomplish on the ARM.
Brad
________________________________
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On
Behalf Of Shawn Ho
Sent: Tuesday, March 04, 2008 12:16 AM
To: [email protected]
Subject: DM355 or DM6437
Hi,
I am new to the DaVinci but very interested in exploring the
capability. There is an opportunity in my company for a machine vision
project. However, I am very confused about many selections of the
DaVinci series. I have read the online webminar as well as some
materials on the DaVinci Wiki. Currently, I am stuck between DM355 and
DM6437.
They are both cost-effective solutions. DM355 seems to be able
to provide more user interface control because of the ARM processor;
while the DM6437 can implement custom filters for image manipulation. I
slightly stand toward DM6437 because we have a licensed CSS 3.1.
However, using the SDK provided by RidgeRun sounds very interesting too.
My question is that if we pick DM355, could I still make a custom image
filter or I can only use the codec provided by TI?
The current goal of the project is to build up an image
stabilization module. The video input is an NTSC source. The module
needs to compensate for the image motion with an external gyro input
(from RS232). Also, we may want to develop nonlinear filter to
compensate for lens distortion in the future as well. Could anyone give
me some valuable suggestions please? Thanks in advance!
Best Regards,
Shawn
_______________________________________________
Davinci-linux-open-source mailing list
[email protected]
http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
