5 Replies Latest reply on May 19, 2017 9:46 AM by brpe_2442836

    Combine UVC and UAC on CX3

      I'm starting a project for a client which requires video from an OV5640 image sensor as well as audio output.  We are considering using the CX3 for this project.  The cycx3_uvc_ov5640 firmware example in the FX3 SDK can be used to stream the video out over USB using UVC.  I also see that there is a cyfxuac example which streams audio over USB using UAC.


      - Will the cyfxuac example run on a CX3, or is it only functional on an FX3?


      - Would it be feasible to combine these 2 firmware examples to enable streaming both video and audio simultaneously using UVC and UAC on a CX3?





        • 1. Re: Combine UVC and UAC on CX3



          Yes, cyfxuac runs on CX3 also. You can combine UAV and UVC Examples. Some of our customers have implemented this.




          - Madhu Sudhan

          • 2. Re: Combine UVC and UAC on CX3

            Thank you for the quick response Madhu!


            I have a couple of follow-up questions.  I'm trying to understand if the CX3 is the right choice for our application, or if maybe it's overkill.  I need to handle 640x480 video at 30 fps, as well as mono audio both in and out of USB. Is the FX2 capable of handling this amount of data, or do I need the CX3?  Or is there a better choice to meet this performance?





            • 3. Re: Combine UVC and UAC on CX3

              Hi Brian,


              FX2 definitely cannot handle this bandwidth. CX3 can support audio and video simultaneously, but I we have not tested the Audi IN / OUT before. We have seen mono audio along with video in a single direction. 


              I am not sure if bidirectional audio could work with the video. If you are interested in trying this out, keep us updated so that we can have discussions on this.




              -Madhu Sudhan

              • 4. Re: Combine UVC and UAC on CX3

                Thanks for the input - it sounds like CX3 is the way to go.  Unfortunately, I need to start on this project now, but the CX3 Denebola dev kits are on back-order and not available for 4 weeks.  Is there another CX3-based dev kit that would allow us to get started on development now?

                • 5. Re: Combine UVC and UAC on CX3

                  Our project requirements have changed slightly since I first posted this question.  I no longer need to support audio over USB - only 640x480 video @30fps over USB 2.0.  I see that the OV5640 sensor is capable of outputting JPEG compressed video, and can be configured to use the MIPI or parallel interface.


                  - Is it feasible to configure the sensor for JPEG output, and then transmit MJPEG-compressed video over USB at 30fps, or can I get the performance I need using uncompressed YUV2 sensor data?


                  - Is there an advantage/disadvantage to using CX3 or FX3?  The OV5640 can use either the MIPI or parallel interface, so I believe either platform would work.  Is there another reason to choose one over the other, such as power usage, since this will be on a battery-powered device?