JPEG Codec Unit(JCU)

Hello all and good day,

I'm new to this project that use RZ1AH custom board - We have video input from sensor which is 640x480.
We use scaler to increase size /on video input/ up to 1024x768 (LCD_XGA) for display;

Is it will be possible to use JPEG Codec Unit(JCU) Driver/JCU Library for a
creating JPEG with size 512 x 384 /need to achive an output stream USB/?

Thank's regards
Sorry if this is not correct subforum for ask this question

  • The JCU cannot reduce the resolution of the the input image. The JCU applies the standard JPEG Part 2, ISO-IEC10918-2 algorithm to reduce the overall size of the image.

  • Hello Michael, it's Ivaylo from Erglon LTD. As my collegue said until now we used in our systems:

    Parallel Video Input: 640x480 

    Prallel Video Output to LCD: 640x480 scaled into the display to 1280x960

    USB video stream: 640 x 480 @ 30 fps

    WiFi video stream: 640 x 480 @ 30 fps

    Video recording: 640 x 480 @ 30 fps

    Video preview: 640 x 480 @ 30 fps

    The problem we face now is that we changed the display to such kind which supports only 1024x768 and does not have built in scaler. We are now trying to find a solution for maintaining all the features we have - stream, recording etc. and to support the new display. I think we will not be able to make all the features above working @ 1024x768  with the 30 fps or I am mistaken? Do you see an option for achieving higher resolution on the display which is different than JCU resolution  or we need to use an external scaler IC to make it?



  • Have you tried the scaler in the RZA VDC5 Scaler block? 

  • Yes, we are using the scaler to make the resolution from 640x480 at the RZA video input to 1024x768 at the Image Synthesizer. We add graphics overlay to the image after that and through OIR we are sending the image ot the LCD and JCU. 

    The question is that until now our input was 640x480 and after OIR we had again 640x480 going to the display. What we are targeting now is 1024x768 and 512x384 or 640x480(in the ideal case) at recording, WiFi stream, USB stream, video preview. 

  • So if I understand the input video has increased in resolution form the original 640x480 to 1024x768 and 512x384. But the fps streaming through put is suffering and you want to use the JCU to compress the image for streaming. And if possible reduce the resolution with out losing image features.  Is that correct?

  • That's correct, Michael. We scale the input image to 1024x768, the graphics overlay is @ 1024x768 too and the mixed video from them both is the JCU and LCD input. We want to reduce the JCU output resolution to be able to maintain reasanoable frame rate for video recording and streaming.

  • So like like I said earlier the JCU does not reduce the resolution it applies the Losey JPEG  compersson algorithm based on DCT to reduce the overall size. If the input image is not YCbCr color format the RZA1H has the Pixel Converter to help with the conversion. 

    To help scale down the resolution a software implementation would be needed. The RZA1 has the ARM Neon coprocessor. The coprocessor is a SIMD processor so it could scale down images quickly.  

  • Hi Svetlio and Ivaylo,

    Just want to ask if your questions are answered now? Did Michael's answers help you? If yes, please confirm so that we can close this thread now. Thank you and have a nice day! 

    RenesasRulz Forum Moderator