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USB superspeed peripherals Forum Discussions

Shafi
Level 3
First solution authored 10 questions asked 25 sign-ins
Level 3

Hi team,

I am trying to get 13MP MJPEG video stream with HS USB 2.0. I have set the resolution successfully but I am getting white screen in directshow based app. In AMCap I was getting  "Unable to render video preview screen".

May I know why it is happening so?

Does USB 2.0 support 13MP MJPEG video stream?

Thank you.

 

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1 Solution
Rashi_Vatsa
Moderator
Moderator 5 likes given 500 solutions authored 1000 replies posted
Moderator

Hello,

Please refer to the AN75779 application note. It mentions that for USB 2.0, the maximum UVC throughput in bytes (frame height × frame width × pixel size × frames per second) should be less than 40-MBps. Note that the observed frames per second will be dependent on the frame blanking and the line blanking times of the image sensor.

Please confirm if this is met in your application. You can also check the UART debug prints to understand if the video data is received by FX3

Regards,
Rashi

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Rashi_Vatsa
Moderator
Moderator 5 likes given 500 solutions authored 1000 replies posted
Moderator

Hello,

Please refer to the AN75779 application note. It mentions that for USB 2.0, the maximum UVC throughput in bytes (frame height × frame width × pixel size × frames per second) should be less than 40-MBps. Note that the observed frames per second will be dependent on the frame blanking and the line blanking times of the image sensor.

Please confirm if this is met in your application. You can also check the UART debug prints to understand if the video data is received by FX3

Regards,
Rashi
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Shafi
Level 3
First solution authored 10 questions asked 25 sign-ins
Level 3

Hi Rashi,

I can able to stream 13MP MJPEG image over USB 2.0 but i cant able to still capture. When I am capturing image, I am getting black color screen. And that image is not supporting in any Photo app.

I have configured the still parameters on descriptor side i.e, still method that i follow, width an height of image etc. I have also made changes on firmware side. 

May I know why this happens?

Thank you,

Shafi.

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Rashi_Vatsa
Moderator
Moderator 5 likes given 500 solutions authored 1000 replies posted
Moderator

Hello Shafi,

Please let me know which among the 3 still capture methods are you implementing in your application

Kindly, share the changes done in the firmware to support the same.

If you want to implement still capture 2 method, please refer to section 2.3.5 of AN75779

Regards,
Rashi
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