hello ! I have a question about bitrate control

[OhsureBoy]

I'm using version acap-sdk-3.5!

To control bitrate

vdo_map_set_uint32(settings, "width", videoCapture->width);
vdo_map_set_uint32(settings, "height", videoCapture->height);
vdo_map_set_uint32(settings, "bitrate", (videoCapture->bitrate *1000)*0.8);
vdo_map_set_uint32(settings, "framerate", (videoCapture->frames));

vdo_map_set_boolean(settings, "dynamic.bitrate", TRUE);
vdo_map_set_uint32(settings, "rc.mode", VDO_RATE_CONTROL_MODE_CBR);

I wrote the source code like this, but the bit rate keeps going up and down. Is there something I missed?

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[Cacsjep]

Did U tried to set dynamic bitrate to false?

[OhsureBoy]

I set it to true to change the bitrate midway.

[Cacsjep]

You could try a vdo map dump to see If there anything enabled that prevent CBR like zip stream

[vivekatoffice]

Hi @OhsureBoy ,
You can explore the new Rate control APIs. Look like there are some changes in the new Axis OS:
You can find full parameters here: Parameter specification RTSP URL

[OhsureBoy]

I'm not sure what that means. Can you show me the document?

[Cacsjep]

https://axiscommunications.github.io/acap-documentation/docs/acap-sdk-version-3/api/src/api/vdostream/html/vdo-map_8h.html#a98b42a54524038a2067ef2c7015c070b

[OhsureBoy]

'dynamic.bitrate':
'format'---------: <uint32 1>
'framerate'------: <uint32 0>
'height'---------: <uint32 1080>
'rc.mode'--------: <uint32 0>
'width'----------: <uint32 1920>

If it prints out like this, is it set up?

But I don't get 3000kbps.

[Cacsjep]

could u show your code to setup the map ?

[OhsureBoy]

vdo_map_set_uint32(settings, "width", 1920);
vdo_map_set_uint32(settings, "height", 1080);
vdo_map_set_uint32(settings, "bitrate", 0);
vdo_map_set_uint32(settings, "framerate", 0);

vdo_map_set_boolean(settings, "dynamic.bitrate", TRUE);
vdo_map_set_uint32(settings, "rc.mode", VDO_RATE_CONTROL_MODE_CBR );
vdo_map_set_uint32(settings, "channel", 5);


--------------------------------------------------------------

VdoMap *settings = vdo_map_new();
    vdo_map_set_uint32(settings, "bitrate",3000);
    vdo_map_set_uint32(settings, "rc.mode", VDO_RATE_CONTROL_MODE_CBR );
    if (!vdo_stream_set_settings(stream, settings, &videoCapture->error)) {
        g_error("\n @@@@@@@@@@ Error: %s\n",  videoCapture->error->message);
    }
    g_object_unref(settings);

[Cacsjep]

try vdo_map_set_boolean(settings, "dynamic.bitrate", FALSE); because you dont want dynamic bitrate

[Cacsjep]

could you try VDO_RATE_CONTROL_MODE_MBR

[OhsureBoy]

once at 1609 kbps
One time it shows 3000 kbps

Is there any way to reduce this variation?

[Cacsjep]

come to my channel its better to chat https://discord.gg/Kdw7vbUn =)

[OhsureBoy]

I adjusted the gop_length and it worked. Thank you very much.