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Returning to the crime scene - or - can we change the audio quality? (Yi Smart Dash Camera)

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  • Returning to the crime scene - or - can we change the audio quality? (Yi Smart Dash Camera)

    Hi all
    I posted in the past my quest for a better audio quality (after buying two dash cameras). I ended up keeping the ZeroGoGo and returning the Safeel One because there was no way to control the IR-cut filter which was constantly turning in and out. So I got decent night video from the ViaGoGo, but the audio was disastrous. ended up getting Yi Smart Dash camera because it was on sale (with F1.8 but sadly US edition with not so good sensor), but again - crap audio.
    I did managed to patch it so it will be 44.1Khz BUT sadly I am unable to change the bitrate from 112Kbps to 192KBps (which is as far as I know the highest rate the AAC-LC supports). The camera "decides" when you go from 32Khz to 44.1Kz to increase the bitrate from 96K to 112K, but even if you go to 48Khz it stays on 112Kbps.

    If anyone is interested - here's the firmware mod, for the CA31A / CABAA (US) models, based the mod provided in the past with high video bitrate:
    https://yadi.sk/d/sBjogalirtKVog


    if anyone know how to raise the AUDIO bitrate please tell (Master nutsey perhaps)?
    I also ordered a new microphone (PANASONIC WM-61A capsule) to try and replace the one that comes with it and see if it will improve audio. If you're interested, the change to 44.1Khz was done by changing addresses 00730804-5 to 44 AC. You can get it to 48khz but AAC-LC isn't really optimized for that, so not really required, and in any case, before anyone can share with me a way to increase the bitrate it's useless (even with a really good microphone).

    Here's what the Novatek SDK tells us about the bitrate:

    Code:
    Audio support bit rate definition
    
    @note Audio support bit rate definition.
    */
    typedef enum _EN_AUDIO_BIT_RATE
    {
    EN_AUDIO_BIT_RATE_NONE = 0x0000, ///< None
    EN_AUDIO_BIT_RATE_16k = 0x0001, ///< 16K
    EN_AUDIO_BIT_RATE_32k = 0x0002, ///< 32K
    EN_AUDIO_BIT_RATE_48k = 0x0003, ///< 48K
    EN_AUDIO_BIT_RATE_64k = 0x0004, ///< 64K
    EN_AUDIO_BIT_RATE_80k = 0x0005, ///< 80K
    EN_AUDIO_BIT_RATE_96k = 0x0006, ///< 96K
    EN_AUDIO_BIT_RATE_112k = 0x0007, ///< 112K
    EN_AUDIO_BIT_RATE_128k = 0x0008, ///< 128K
    EN_AUDIO_BIT_RATE_144k = 0x0009, ///< 144K
    EN_AUDIO_BIT_RATE_160k = 0x000A, ///< 160K
    EN_AUDIO_BIT_RATE_192k = 0x000B, ///< 192K
    EN_AUDIO_BIT_RATE_TOTAL
    }EN_AUDIO_BIT_RATE;[
    
    /CODE]
    
    
    
    
    Last but not least - according to the Novatek SDK there is supposed to be also cut-off frequency control - but I have no clue where it's located or if its implemented. I assume it is because all these dash camera seems to just follow the standard Novatek SDK...
    
    
    [CODE
    ]typedef enum _EN_AUDIO_ENC_STOP_FREQ
    {
    EN_AUDIO_ENC_STOP_FREQ_08K = 0x0000, ///< 8KHz
    EN_AUDIO_ENC_STOP_FREQ_10K = 0x0001, ///< 10KHz
    EN_AUDIO_ENC_STOP_FREQ_11K = 0x0002, ///< 11KHz
    EN_AUDIO_ENC_STOP_FREQ_12K = 0x0003, ///< 12KHz
    EN_AUDIO_ENC_STOP_FREQ_14K = 0x0004, ///< 14KHz
    EN_AUDIO_ENC_STOP_FREQ_16K = 0x0005, ///< 16KHz
    EN_AUDIO_ENC_STOP_FREQ_18K = 0x0006, ///< 18KHz
    EN_AUDIO_ENC_STOP_FREQ_20K = 0x0007, ///< 20KHz
    EN_AUDIO_ENC_STOP_FREQ_24K = 0x0008, ///< 24KHz
    EN_AUDIO_ENC_STOP_FREQ_TOTAL
    } EN_AUDIO_ENC_STOP_FREQ;



    Thank you to everyone who could help!

    PS
    I actually use the dash camera for night video shoot of live music events I participate in, where there is not a lot of light, therefore the interest in the audio.

  • #2
    Originally posted by BlueDan View Post
    I actually use the dash camera for night video shoot of live music events I participate in, where there is not a lot of light, therefore the interest in the audio.
    Hi,

    You might want something more low-light capable like a dash or even IP cam with an IMX327 inside. And if I was participating any music events I would use a dedicated stero sound recording device.
    Donate here if you want to support my efforts and this site.

    Email me if you have any offers, requests or ideas.

    Comment


    • #3
      That's a great looking nighttime sensor, but I only see the Caddx model and nothing else with that sensor...are there other cameras that feature this?
      https://www.amazon.com/dp/B07VHQBVL4...osi&th=1&psc=1
      Last edited by 5prock3t; 4 weeks ago. Reason: Stupid link didnt work

      Comment


      • nutsey
        nutsey commented
        Editing a comment
        Blueskysea Mini 0906 PRO dashcam.
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