6DL / 6S Dual Video Encode Capability

[mhilt]

I have seen a few similar questions, but none that seem to say for certain what the capability limits are and relationship to memory clocks, memory width, VPU clock, and cpu utilization. These threads appear to indicate it is possible, but I need to know before committing to an i.MX6 part.

My application requires simultaneous 2x camera video input, with 2x h.264 encode. Ideal is 2x 720p30.

6Solo is preferred for cost.

Are 6Solo and/or 6DualLite capable of 2x 720p30? At what VPU clock? Bus utilization estimate? CPU utilization estimate? Possible within Linux?

Thanks,

Matt

[joanxie]

yes vpu can support 2x720P@30 encoding(h264 bp profile), vpu clock rate is 266MHZ, because vpu is hardware module, so this performance is for hardware encoding.for cpu performance, which depends on your actual case. th

[erdani80]

We are developing an application using a dual camera sensor. The development now is being done in a dev kit with a quad processor running linux.

We disabled 3 cores to make the system behave as a solo configuration, which is our target system or the custom hardware.

The application is able to take video from two sensors, compress it using h.264 and send it over RTSP. The CPU utilization is about 80%, but this figure also includes features in our application apart from the video.

[mhilt]

Thanks for the info Daniel. That is somewhat encouraging. Couple other questions if you don't mind me asking:

I assume you are doing the h.264 encoding with the HW encoder, not software? What resolution and frame rate? Are both your sensors on the parallel interfaces?

Do you have the CPU clocked at 1.2GHz or 1GHz? I have also had some concern with the 32b vs 64b memory bus on the 6Solo, but from a few quick estimates it doesn't look like memory bandwidth is going to be an issue.

Which dev board are you working with? We were hoping to use a board with a 6Solo or 6DualLite, but I am also looking for one that ideally exposes both parallel camera interfaces.

[erdani80]

We are using the HW encoder, I believe that SW encoding cannot get that performance. The dev kit we are using is a MCIMX6Q-SDP an dthe sensors are the ones included, one parallel and one mipi. Regarding the resolution I have to check but one of the sensors is HD and we are using 30FPS for one stream and the second stream has a configurable FPS rate, but up to 30FPS has been tested.

REgarding the CPU utilization, our forst tests show that most CPU is used in the RTSP server and some of the gstreamers blocks we have added for the application we are developing. I cannot provide more info regarding the application.

I haven't seen a dev kit with both parallel sensors, in fact looking at th RM you can see that the first parallel bus has some lines that are used bor bootstrap, so extra logic (or a multiplexer) needs to be added in order to get the processor properly booting. I can't remember if this problem only happen when the camera bus has more than 8 bits.

As far as I know this hardware is clcoked at 1.2GHz and 64b memory bus, our first try was reducing the number of cores and now we will continue adding changes to the clocks and memory configuraion so that this matches close to the imx6solo.

We will release a module with dual camera interface and imx6sdq capability but this will be released along the year and it will only be supplied in a per project basis, at least initially.